Changeset 90152a4 for src/SymTab

Timestamp:

Aug 27, 2018, 4:40:34 PM (7 years ago)

Author:

Rob Schluntz <rschlunt@…>

Branches:

ADT, arm-eh, ast-experimental, cleanup-dtors, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

b7c89aa

Parents:

f9feab8 (diff), 305581d (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge branch 'master' into cleanup-dtors

Location:

src/SymTab

Files:

• AddVisit.h (deleted)
• Autogen.cc (modified) (4 diffs)
• Demangle.cc (added)
• FixFunction.cc (modified) (3 diffs)
• FixFunction.h (modified) (1 diff)
• Indexer.cc (modified) (25 diffs)
• Indexer.h (modified) (6 diffs)
• Mangler.cc (modified) (2 diffs)
• Mangler.h (modified) (1 diff)
• ManglerCommon.cc (added)
• Validate.cc (modified) (44 diffs)
• demangler.cc (added)
• module.mk (modified) (1 diff)

src/SymTab/Autogen.cc

@@ -9 +9 @@
 // Author           : Rob Schluntz
 // Created On       : Thu Mar 03 15:45:56 2016
-// Last Modified By : Andrew Beach
-// Last Modified On : Fri Jul 14 16:41:00 2017
-// Update Count     : 62
+// Last Modified By : Peter A. Buhr
+// Last Modified On : Fri Apr 27 14:39:06 2018
+// Update Count     : 63
 //
 
@@ -24 +24 @@
 #include <vector>                  // for vector
 
-#include "AddVisit.h"              // for addVisit
 #include "CodeGen/OperatorTable.h" // for isCtorDtor, isCtorDtorAssign
 #include "Common/PassVisitor.h"    // for PassVisitor
@@ -335 +334 @@
                         definitions.push_back( dcl );
                         indexer.addId( dcl );
-                } catch ( SemanticError err ) {
+                } catch ( SemanticErrorException & ) {
                         // okay if decl does not resolve - that means the function should not be generated
                         delete dcl;
@@ -380 +379 @@
                         paramType->attributes.clear();
                         // add a parameter corresponding to this field
-                        memCtorType->parameters.push_back( new ObjectDecl( field->name, Type::StorageClasses(), LinkageSpec::Cforall, nullptr, paramType, nullptr ) );
+                        ObjectDecl * param = new ObjectDecl( field->name, Type::StorageClasses(), LinkageSpec::Cforall, nullptr, paramType, nullptr );
+                        cloneAll_if( field->attributes, param->attributes, [](Attribute * attr) { return attr->isValidOnFuncParam(); } );
+                        memCtorType->parameters.push_back( param );
                         FunctionDecl * ctor = genFunc( "?{}", memCtorType->clone(), functionNesting );
                         makeFieldCtorBody( aggregateDecl->members.begin(), aggregateDecl->members.end(), ctor );

src/SymTab/FixFunction.cc

@@ -30 +30 @@
                 // can't delete function type because it may contain assertions, so transfer ownership to new object
                 ObjectDecl *pointer = new ObjectDecl( functionDecl->name, functionDecl->get_storageClasses(), functionDecl->linkage, nullptr, new PointerType( Type::Qualifiers(), functionDecl->type ), nullptr, functionDecl->attributes );
+                pointer->location = functionDecl->location;
                 functionDecl->attributes.clear();
                 functionDecl->type = nullptr;
@@ -36 +37 @@
         }
 
+        // xxx - this passes on void[], e.g.
+        //   void foo(void [10]);
+        // does not cause an error
+
         Type * FixFunction::postmutate(ArrayType *arrayType) {
                 // need to recursively mutate the base type in order for multi-dimensional arrays to work.
                 PointerType *pointerType = new PointerType( arrayType->get_qualifiers(), arrayType->base, arrayType->dimension, arrayType->isVarLen, arrayType->isStatic );
+                pointerType->location = arrayType->location;
                 arrayType->base = nullptr;
                 arrayType->dimension = nullptr;
@@ -62 +68 @@
         void FixFunction::premutate(ZeroType *) { visit_children = false; }
         void FixFunction::premutate(OneType *) { visit_children = false; }
+
+        bool fixFunction( DeclarationWithType *& dwt ) {
+                PassVisitor<FixFunction> fixer;
+                dwt = dwt->acceptMutator( fixer );
+                return fixer.pass.isVoid;
+        }
 } // namespace SymTab
 

src/SymTab/FixFunction.h

@@ -47 +47 @@
                 bool isVoid;
         };
+
+        bool fixFunction( DeclarationWithType *& );
 } // namespace SymTab
 

src/SymTab/Indexer.cc

@@ -26 +26 @@
 #include "Common/SemanticError.h"  // for SemanticError
 #include "Common/utility.h"        // for cloneAll
+#include "GenPoly/GenPoly.h"
 #include "InitTweak/InitTweak.h"   // for isConstructor, isCopyFunction, isC...
 #include "Mangler.h"               // for Mangler
@@ -105 +106 @@
                 if ( ! CodeGen::isCtorDtorAssign( id ) ) return;
 
-                // helpful data structure
+                // helpful data structure to organize properties for a type
                 struct ValueType {
-                        struct DeclBall {
+                        struct DeclBall { // properties for this particular decl
                                 IdData decl;
-                                bool isUserDefinedFunc; // properties for this particular decl
-                                bool isDefaultCtor;
-                                bool isDtor;
+                                bool isUserDefinedFunc;
                                 bool isCopyFunc;
                         };
                         // properties for this type
-                        bool existsUserDefinedFunc = false;    // any user-defined function found
-                        bool existsUserDefinedCtor = false;    // any user-defined constructor found
-                        bool existsUserDefinedDtor = false;    // any user-defined destructor found
                         bool existsUserDefinedCopyFunc = false;    // user-defined copy ctor found
-                        bool existsUserDefinedDefaultCtor = false; // user-defined default ctor found
+                        BaseSyntaxNode * deleteStmt = nullptr;     // non-null if a user-defined function is found
                         std::list< DeclBall > decls;
 
@@ -126 +122 @@
                         ValueType & operator+=( IdData data ) {
                                 DeclarationWithType * function = data.id;
-                                bool isUserDefinedFunc = ! LinkageSpec::isOverridable( function->get_linkage() );
-                                bool isDefaultCtor = InitTweak::isDefaultConstructor( function );
-                                bool isDtor = InitTweak::isDestructor( function );
-                                bool isCopyFunc = InitTweak::isCopyFunction( function, function->get_name() );
-                                decls.push_back( DeclBall{ data, isUserDefinedFunc, isDefaultCtor, isDtor, isCopyFunc } );
-                                existsUserDefinedFunc = existsUserDefinedFunc || isUserDefinedFunc;
-                                existsUserDefinedCtor = existsUserDefinedCtor || (isUserDefinedFunc && CodeGen::isConstructor( function->get_name() ) );
-                                existsUserDefinedDtor = existsUserDefinedDtor || (isUserDefinedFunc && isDtor);
+                                bool isUserDefinedFunc = ! LinkageSpec::isOverridable( function->linkage );
+                                bool isCopyFunc = InitTweak::isCopyFunction( function, function->name );
+                                decls.push_back( DeclBall{ data, isUserDefinedFunc, isCopyFunc } );
                                 existsUserDefinedCopyFunc = existsUserDefinedCopyFunc || (isUserDefinedFunc && isCopyFunc);
-                                existsUserDefinedDefaultCtor = existsUserDefinedDefaultCtor || (isUserDefinedFunc && isDefaultCtor);
+                                if ( isUserDefinedFunc && ! deleteStmt ) {
+                                        // any user-defined function can act as an implicit delete statement for generated constructors.
+                                        // a delete stmt should not act as an implicit delete statement.
+                                        deleteStmt = data.id;
+                                }
                                 return *this;
                         }
@@ -147 +142 @@
                 for ( auto decl : copy ) {
                         if ( FunctionDecl * function = dynamic_cast< FunctionDecl * >( decl.id ) ) {
-                                std::list< DeclarationWithType * > & params = function->get_functionType()->get_parameters();
+                                std::list< DeclarationWithType * > & params = function->type->parameters;
                                 assert( ! params.empty() );
                                 // use base type of pointer, so that qualifiers on the pointer type aren't considered.
@@ -159 +154 @@
 
                 // if a type contains user defined ctor/dtor/assign, then special rules trigger, which determine
-                // the set of ctor/dtor/assign that are seen by the requester. In particular, if the user defines
-                // a default ctor, then the generated default ctor should never be seen, likewise for copy ctor
-                // and dtor. If the user defines any ctor/dtor, then no generated field ctors should be seen.
-                // If the user defines any ctor then the generated default ctor should not be seen (intrinsic default
-                // ctor must be overridden exactly).
+                // the set of ctor/dtor/assign that can be used  by the requester. In particular, if the user defines
+                // a default ctor, then the generated default ctor is unavailable, likewise for copy ctor
+                // and dtor. If the user defines any ctor/dtor, then no generated field ctors are available.
+                // If the user defines any ctor then the generated default ctor is unavailable (intrinsic default
+                // ctor must be overridden exactly). If the user defines anything that looks like a copy constructor,
+                // then the generated copy constructor is unavailable, and likewise for the assignment operator.
                 for ( std::pair< const std::string, ValueType > & pair : funcMap ) {
                         ValueType & val = pair.second;
                         for ( ValueType::DeclBall ball : val.decls ) {
-                                bool noUserDefinedFunc = ! val.existsUserDefinedFunc;
-                                bool isUserDefinedFunc = ball.isUserDefinedFunc;
-                                bool isAcceptableDefaultCtor = (! val.existsUserDefinedCtor || (! val.existsUserDefinedDefaultCtor && ball.decl.id->get_linkage() == LinkageSpec::Intrinsic)) && ball.isDefaultCtor; // allow default constructors only when no user-defined constructors exist, except in the case of intrinsics, which require exact overrides
-                                bool isAcceptableCopyFunc = ! val.existsUserDefinedCopyFunc && ball.isCopyFunc; // handles copy ctor and assignment operator
-                                bool isAcceptableDtor = ! val.existsUserDefinedDtor && ball.isDtor;
-                                if ( noUserDefinedFunc || isUserDefinedFunc || isAcceptableDefaultCtor || isAcceptableCopyFunc || isAcceptableDtor ) {
-                                        // decl conforms to the rules described above, so it should be seen by the requester
-                                        out.push_back( ball.decl );
+                                bool isNotUserDefinedFunc = ! ball.isUserDefinedFunc && ball.decl.id->linkage != LinkageSpec::Intrinsic;
+                                bool isCopyFunc = ball.isCopyFunc;
+                                bool existsUserDefinedCopyFunc = val.existsUserDefinedCopyFunc;
+
+                                // only implicitly delete non-user defined functions that are not intrinsic, and are
+                                // not copy functions (assignment or copy constructor). If a  user-defined copy function exists,
+                                // do not pass along the non-user-defined copy functions since signatures do not have to match,
+                                // and the generated functions will often be cheaper.
+                                if ( isNotUserDefinedFunc ) {
+                                        if ( isCopyFunc ) {
+                                                // Skip over non-user-defined copy functions when there is a user-defined copy function.
+                                                // Since their signatures do not have to be exact, deleting them is the wrong choice.
+                                                if ( existsUserDefinedCopyFunc ) continue;
+                                        } else {
+                                                // delete non-user-defined non-copy functions if applicable.
+                                                // deleteStmt will be non-null only if a user-defined function is found.
+                                                ball.decl.deleteStmt = val.deleteStmt;
+                                        }
                                 }
+                                out.push_back( ball.decl );
                         }
                 }
@@ -265 +272 @@
         }
 
+        NamedTypeDecl *Indexer::globalLookupType( const std::string &id ) const {
+                return lookupTypeAtScope( id, 0 );
+        }
+
+        StructDecl *Indexer::globalLookupStruct( const std::string &id ) const {
+                return lookupStructAtScope( id, 0 );
+        }
+
+        UnionDecl *Indexer::globalLookupUnion( const std::string &id ) const {
+                return lookupUnionAtScope( id, 0 );
+        }
+
+        EnumDecl *Indexer::globalLookupEnum( const std::string &id ) const {
+                return lookupEnumAtScope( id, 0 );
+        }
+
         EnumDecl *Indexer::lookupEnum( const std::string &id ) const {
                 if ( ! tables ) return 0;
@@ -286 +309 @@
         }
 
-        DeclarationWithType *Indexer::lookupIdAtScope( const std::string &id, const std::string &mangleName, unsigned long scope ) const {
-                if ( ! tables ) return 0;
-                if ( tables->scope < scope ) return 0;
+        const Indexer::IdData * Indexer::lookupIdAtScope( const std::string &id, const std::string &mangleName, unsigned long scope ) const {
+                if ( ! tables ) return nullptr;
+                if ( tables->scope < scope ) return nullptr;
 
                 IdTable::const_iterator decls = tables->idTable.find( id );
@@ -294 +317 @@
                         const MangleTable &mangleTable = decls->second;
                         MangleTable::const_iterator decl = mangleTable.find( mangleName );
-                        if ( decl != mangleTable.end() ) return decl->second.id;
+                        if ( decl != mangleTable.end() ) return &decl->second;
                 }
 
                 return tables->base.lookupIdAtScope( id, mangleName, scope );
+        }
+
+        Indexer::IdData * Indexer::lookupIdAtScope( const std::string &id, const std::string &mangleName, unsigned long scope ) {
+                return const_cast<IdData *>(const_cast<const Indexer *>(this)->lookupIdAtScope( id, mangleName, scope ));
         }
 
@@ -336 +363 @@
                 if ( ! tables ) return 0;
                 if ( tables->scope < scope ) return 0;
+                if ( tables->scope > scope ) return tables->base.lookupTypeAtScope( id, scope );
 
                 TypeTable::const_iterator ret = tables->typeTable.find( id );
@@ -344 +372 @@
                 if ( ! tables ) return 0;
                 if ( tables->scope < scope ) return 0;
+                if ( tables->scope > scope ) return tables->base.lookupStructAtScope( id, scope );
 
                 StructTable::const_iterator ret = tables->structTable.find( id );
@@ -352 +381 @@
                 if ( ! tables ) return 0;
                 if ( tables->scope < scope ) return 0;
+                if ( tables->scope > scope ) return tables->base.lookupEnumAtScope( id, scope );
 
                 EnumTable::const_iterator ret = tables->enumTable.find( id );
@@ -360 +390 @@
                 if ( ! tables ) return 0;
                 if ( tables->scope < scope ) return 0;
+                if ( tables->scope > scope ) return tables->base.lookupUnionAtScope( id, scope );
 
                 UnionTable::const_iterator ret = tables->unionTable.find( id );
@@ -368 +399 @@
                 if ( ! tables ) return 0;
                 if ( tables->scope < scope ) return 0;
+                if ( tables->scope > scope ) return tables->base.lookupTraitAtScope( id, scope );
 
                 TraitTable::const_iterator ret = tables->traitTable.find( id );
@@ -373 +405 @@
         }
 
-        bool addedIdConflicts( DeclarationWithType *existing, DeclarationWithType *added ) {
+        bool isFunction( DeclarationWithType * decl ) {
+                return GenPoly::getFunctionType( decl->get_type() );
+        }
+
+        bool isObject( DeclarationWithType * decl ) {
+                return ! isFunction( decl );
+        }
+
+        bool isDefinition( DeclarationWithType * decl ) {
+                if ( FunctionDecl * func = dynamic_cast< FunctionDecl * >( decl ) ) {
+                        // a function is a definition if it has a body
+                        return func->statements;
+                } else {
+                        // an object is a definition if it is not marked extern.
+                        // both objects must be marked extern
+                        return ! decl->get_storageClasses().is_extern;
+                }
+        }
+
+        bool addedIdConflicts( Indexer::IdData & existing, DeclarationWithType *added, BaseSyntaxNode * deleteStmt, Indexer::ConflictFunction handleConflicts ) {
                 // if we're giving the same name mangling to things of different types then there is something wrong
-                assert( (dynamic_cast<ObjectDecl*>( added ) && dynamic_cast<ObjectDecl*>( existing ) )
-                        || (dynamic_cast<FunctionDecl*>( added ) && dynamic_cast<FunctionDecl*>( existing ) ) );
-
-                if ( LinkageSpec::isOverridable( existing->get_linkage() ) ) {
+                assert( (isObject( added ) && isObject( existing.id ) )
+                        || ( isFunction( added ) && isFunction( existing.id ) ) );
+
+                if ( LinkageSpec::isOverridable( existing.id->get_linkage() ) ) {
                         // new definition shadows the autogenerated one, even at the same scope
                         return false;
-                } else if ( LinkageSpec::isMangled( added->get_linkage() ) || ResolvExpr::typesCompatible( added->get_type(), existing->get_type(), Indexer() ) ) {
-                        // typesCompatible doesn't really do the right thing here. When checking compatibility of function types,
-                        // we should ignore outermost pointer qualifiers, except _Atomic?
-                        FunctionDecl *newentry = dynamic_cast< FunctionDecl* >( added );
-                        FunctionDecl *oldentry = dynamic_cast< FunctionDecl* >( existing );
-                        if ( newentry && oldentry ) {
-                                if ( newentry->get_statements() && oldentry->get_statements() ) {
-                                        throw SemanticError( "duplicate function definition for ", added );
-                                } // if
-                        } else {
-                                // two objects with the same mangled name defined in the same scope.
-                                // both objects must be marked extern or both must be intrinsic for this to be okay
-                                // xxx - perhaps it's actually if either is intrinsic then this is okay?
-                                //       might also need to be same storage class?
-                                ObjectDecl *newobj = dynamic_cast< ObjectDecl* >( added );
-                                ObjectDecl *oldobj = dynamic_cast< ObjectDecl* >( existing );
-                                if ( ! newobj->get_storageClasses().is_extern && ! oldobj->get_storageClasses().is_extern ) {
-                                        throw SemanticError( "duplicate object definition for ", added );
+                } else if ( LinkageSpec::isMangled( added->get_linkage() ) || ResolvExpr::typesCompatible( added->get_type(), existing.id->get_type(), Indexer() ) ) {
+
+                        // it is a conflict if one declaration is deleted and the other is not
+                        if ( deleteStmt && ! existing.deleteStmt ) {
+                                return handleConflicts( existing, "deletion of defined identifier " );
+                        } else if ( ! deleteStmt && existing.deleteStmt ) {
+                                return handleConflicts( existing, "definition of deleted identifier " );
+                        }
+
+                        if ( isDefinition( added ) && isDefinition( existing.id ) ) {
+                                if ( isFunction( added ) ) {
+                                        return handleConflicts( existing, "duplicate function definition for " );
+                                } else {
+                                        return handleConflicts( existing, "duplicate object definition for " );
                                 } // if
                         } // if
                 } else {
-                        throw SemanticError( "duplicate definition for ", added );
+                        return handleConflicts( existing, "duplicate definition for " );
                 } // if
 
@@ -408 +455 @@
         }
 
-        void Indexer::addId( DeclarationWithType *decl, Expression * baseExpr ) {
+        void Indexer::addId( DeclarationWithType *decl, ConflictFunction handleConflicts, Expression * baseExpr, BaseSyntaxNode * deleteStmt ) {
+                if ( decl->name == "" ) return;
                 debugPrint( "Adding Id " << decl->name << std::endl );
                 makeWritable();
@@ -430 +478 @@
                         // isomorphic to C type-compatibility, which it may not be.
                         if ( hasIncompatibleCDecl( name, mangleName, scope ) ) {
-                                throw SemanticError( "conflicting overload of C function ", decl );
-                        }
-                } else {
-                        // Check that a Cforall declaration doesn't overload any C declaration
+                                SemanticError( decl, "conflicting overload of C function " );
+                        }
+                } else {
+                        // Check that a Cforall declaration doesn't override any C declaration
                         if ( hasCompatibleCDecl( name, mangleName, scope ) ) {
-                                throw SemanticError( "Cforall declaration hides C function ", decl );
+                                SemanticError( decl, "Cforall declaration hides C function " );
                         }
                 }
 
                 // Skip repeat declarations of the same identifier
-                DeclarationWithType *existing = lookupIdAtScope( name, mangleName, scope );
-                if ( existing && addedIdConflicts( existing, decl ) ) return;
+                IdData * existing = lookupIdAtScope( name, mangleName, scope );
+                if ( existing && existing->id && addedIdConflicts( *existing, decl, deleteStmt, handleConflicts ) ) return;
 
                 // add to indexer
-                tables->idTable[ name ][ mangleName ] = { decl, baseExpr };
+                tables->idTable[ name ][ mangleName ] = IdData{ decl, baseExpr, deleteStmt };
                 ++tables->size;
         }
 
+        void Indexer::addId( DeclarationWithType * decl, Expression * baseExpr ) {
+                // default handling of conflicts is to raise an error
+                addId( decl, [decl](IdData &, const std::string & msg) { SemanticError( decl, msg ); return true; }, baseExpr, decl->isDeleted ? decl : nullptr );
+        }
+
+        void Indexer::addDeletedId( DeclarationWithType * decl, BaseSyntaxNode * deleteStmt ) {
+                // default handling of conflicts is to raise an error
+                addId( decl, [decl](IdData &, const std::string & msg) { SemanticError( decl, msg ); return true; }, nullptr, deleteStmt );
+        }
+
         bool addedTypeConflicts( NamedTypeDecl *existing, NamedTypeDecl *added ) {
-                if ( existing->get_base() == 0 ) {
+                if ( existing->base == nullptr ) {
                         return false;
-                } else if ( added->get_base() == 0 ) {
+                } else if ( added->base == nullptr ) {
                         return true;
                 } else {
-                        throw SemanticError( "redeclaration of ", added );
-                }
+                        assert( existing->base && added->base );
+                        // typedef redeclarations are errors only if types are different
+                        if ( ! ResolvExpr::typesCompatible( existing->base, added->base, Indexer() ) ) {
+                                SemanticError( added->location, "redeclaration of " + added->name );
+                        }
+                }
+                // does not need to be added to the table if both existing and added have a base that are the same
+                return true;
         }
 
@@ -462 +526 @@
                 makeWritable();
 
-                const std::string &id = decl->get_name();
+                const std::string &id = decl->name;
                 TypeTable::iterator existing = tables->typeTable.find( id );
                 if ( existing == tables->typeTable.end() ) {
@@ -478 +542 @@
 
         bool addedDeclConflicts( AggregateDecl *existing, AggregateDecl *added ) {
-                if ( existing->get_members().empty() ) {
+                if ( ! existing->body ) {
                         return false;
-                } else if ( ! added->get_members().empty() ) {
-                        throw SemanticError( "redeclaration of ", added );
+                } else if ( added->body ) {
+                        SemanticError( added, "redeclaration of " );
                 } // if
                 return true;
@@ -495 +559 @@
                 makeWritable();
 
-                const std::string &id = decl->get_name();
+                const std::string &id = decl->name;
                 StructTable::iterator existing = tables->structTable.find( id );
                 if ( existing == tables->structTable.end() ) {
@@ -514 +578 @@
                 makeWritable();
 
-                const std::string &id = decl->get_name();
+                const std::string &id = decl->name;
                 EnumTable::iterator existing = tables->enumTable.find( id );
                 if ( existing == tables->enumTable.end() ) {
@@ -538 +602 @@
                 makeWritable();
 
-                const std::string &id = decl->get_name();
+                const std::string &id = decl->name;
                 UnionTable::iterator existing = tables->unionTable.find( id );
                 if ( existing == tables->unionTable.end() ) {
@@ -557 +621 @@
                 makeWritable();
 
-                const std::string &id = decl->get_name();
+                const std::string &id = decl->name;
                 TraitTable::iterator existing = tables->traitTable.find( id );
                 if ( existing == tables->traitTable.end() ) {
@@ -572 +636 @@
         }
 
-        void Indexer::addWith( WithStmt * stmt ) {
-                for ( Expression * expr : stmt->exprs ) {
+        void Indexer::addMembers( AggregateDecl * aggr, Expression * expr, ConflictFunction handleConflicts ) {
+                for ( Declaration * decl : aggr->members ) {
+                        if ( DeclarationWithType * dwt = dynamic_cast< DeclarationWithType * >( decl ) ) {
+                                addId( dwt, handleConflicts, expr );
+                                if ( dwt->name == "" ) {
+                                        Type * t = dwt->get_type()->stripReferences();
+                                        if ( dynamic_cast< StructInstType * >( t ) || dynamic_cast< UnionInstType * >( t ) ) {
+                                                Expression * base = expr->clone();
+                                                ResolvExpr::Cost cost = ResolvExpr::Cost::zero; // xxx - carry this cost into the indexer as a base cost?
+                                                ResolvExpr::referenceToRvalueConversion( base, cost );
+                                                addMembers( t->getAggr(), new MemberExpr( dwt, base ), handleConflicts );
+                                        }
+                                }
+                        }
+                }
+        }
+
+        void Indexer::addWith( std::list< Expression * > & withExprs, BaseSyntaxNode * withStmt ) {
+                for ( Expression * expr : withExprs ) {
                         if ( expr->result ) {
                                 AggregateDecl * aggr = expr->result->stripReferences()->getAggr();
                                 assertf( aggr, "WithStmt expr has non-aggregate type: %s", toString( expr->result ).c_str() );
 
-                                for ( Declaration * decl : aggr->members ) {
-                                        if ( DeclarationWithType * dwt = dynamic_cast< DeclarationWithType * >( decl ) ) {
-                                                addId( dwt, expr );
-                                        }
-                                }
+                                addMembers( aggr, expr, [withStmt](IdData & existing, const std::string &) {
+                                        // on conflict, delete the identifier
+                                        existing.deleteStmt = withStmt;
+                                        return true;
+                                });
                         }
                 }
@@ -641 +722 @@
 
         void Indexer::print( std::ostream &os, int indent ) const {
-            using std::cerr;
+                using std::cerr;
 
                 if ( tables ) {
@@ -666 +747 @@
         }
 
-        Expression * Indexer::IdData::combine() const {
+        Expression * Indexer::IdData::combine( ResolvExpr::Cost & cost ) const {
+                Expression * ret = nullptr;
                 if ( baseExpr ) {
                         Expression * base = baseExpr->clone();
-                        ResolvExpr::referenceToRvalueConversion( base );
-                        Expression * ret = new MemberExpr( id, base );
+                        ResolvExpr::referenceToRvalueConversion( base, cost );
+                        ret = new MemberExpr( id, base );
                         // xxx - this introduces hidden environments, for now remove them.
                         // std::swap( base->env, ret->env );
                         delete base->env;
                         base->env = nullptr;
-                        return ret;
-                } else {
-                        return new VariableExpr( id );
-                }
+                } else {
+                        ret = new VariableExpr( id );
+                }
+                if ( deleteStmt ) ret = new DeletedExpr( ret, deleteStmt );
+                return ret;
         }
 } // namespace SymTab

src/SymTab/Indexer.h

@@ -19 +19 @@
 #include <list>               // for list
 #include <string>             // for string
+#include <functional>         // for function
 
 #include "SynTree/Visitor.h"  // for Visitor
 #include "SynTree/SynTree.h"  // for AST nodes
+
+namespace ResolvExpr {
+class Cost;
+}
 
 namespace SymTab {
@@ -40 +45 @@
 
                 struct IdData {
-                        DeclarationWithType * id;
-                        Expression * baseExpr; // WithExpr
+                        DeclarationWithType * id = nullptr;
+                        Expression * baseExpr = nullptr; // WithExpr
 
-                        Expression * combine() const;
+                        /// non-null if this declaration is deleted
+                        BaseSyntaxNode * deleteStmt = nullptr;
+
+                        // NOTE: shouldn't need either of these constructors, but gcc-4 does not properly support initializer lists with default members.
+                        IdData() = default;
+                        IdData( DeclarationWithType * id, Expression * baseExpr, BaseSyntaxNode * deleteStmt ) : id( id ), baseExpr( baseExpr ), deleteStmt( deleteStmt ) {}
+
+                        Expression * combine( ResolvExpr::Cost & cost ) const;
                 };
 
@@ -59 +71 @@
                 TraitDecl *lookupTrait( const std::string &id ) const;
 
+                /// Gets the type declaration with the given ID at global scope
+                NamedTypeDecl *globalLookupType( const std::string &id ) const;
+                /// Gets the struct declaration with the given ID at global scope
+                StructDecl *globalLookupStruct( const std::string &id ) const;
+                /// Gets the union declaration with the given ID at global scope
+                UnionDecl *globalLookupUnion( const std::string &id ) const;
+                /// Gets the enum declaration with the given ID at global scope
+                EnumDecl *globalLookupEnum( const std::string &id ) const;
+
                 void print( std::ostream &os, int indent = 0 ) const;
 
                 /// looks up a specific mangled ID at the given scope
-                DeclarationWithType *lookupIdAtScope( const std::string &id, const std::string &mangleName, unsigned long scope ) const;
+                IdData * lookupIdAtScope( const std::string &id, const std::string &mangleName, unsigned long scope );
+                const IdData * lookupIdAtScope( const std::string &id, const std::string &mangleName, unsigned long scope ) const;
                 /// returns true if there exists a declaration with C linkage and the given name with a different mangled name
                 bool hasIncompatibleCDecl( const std::string &id, const std::string &mangleName, unsigned long scope ) const;
@@ -74 +96 @@
                 TraitDecl *lookupTraitAtScope( const std::string &id, unsigned long scope ) const;
 
-                void addId( DeclarationWithType *decl, Expression * baseExpr = nullptr );
+                typedef std::function<bool(IdData &, const std::string &)> ConflictFunction;
+
+                void addId( DeclarationWithType * decl, Expression * baseExpr = nullptr );
+                void addDeletedId( DeclarationWithType * decl, BaseSyntaxNode * deleteStmt );
+
                 void addType( NamedTypeDecl *decl );
                 void addStruct( const std::string &id );
@@ -84 +110 @@
 
                 /// adds all of the IDs from WithStmt exprs
-                void addWith( WithStmt * );
+                void addWith( std::list< Expression * > & withExprs, BaseSyntaxNode * withStmt );
+
+                /// adds all of the members of the Aggregate (addWith helper)
+                void addMembers( AggregateDecl * aggr, Expression * expr, ConflictFunction );
 
                 /// convenience function for adding a list of Ids to the indexer
@@ -114 +143 @@
                 /// Ensures that tables variable is writable (i.e. allocated, uniquely owned by this Indexer, and at the current scope)
                 void makeWritable();
+
+                /// common code for addId, addDeletedId, etc.
+                void addId( DeclarationWithType * decl, ConflictFunction, Expression * baseExpr = nullptr, BaseSyntaxNode * deleteStmt = nullptr );
         };
 } // namespace SymTab

src/SymTab/Mangler.cc

@@ -23 +23 @@
 
 #include "CodeGen/OperatorTable.h"  // for OperatorInfo, operatorLookup
+#include "Common/PassVisitor.h"
 #include "Common/SemanticError.h"   // for SemanticError
 #include "Common/utility.h"         // for toString
@@ -31 +32 @@
 
 namespace SymTab {
-        std::string Mangler::mangleType( Type * ty ) {
-                Mangler mangler( false, true, true );
-                maybeAccept( ty, mangler );
-                return mangler.get_mangleName();
-        }
-
-        std::string Mangler::mangleConcrete( Type* ty ) {
-                Mangler mangler( false, false, false );
-                maybeAccept( ty, mangler );
-                return mangler.get_mangleName();
-        }
-
-        Mangler::Mangler( bool mangleOverridable, bool typeMode, bool mangleGenericParams )
-                : nextVarNum( 0 ), isTopLevel( true ), mangleOverridable( mangleOverridable ), typeMode( typeMode ), mangleGenericParams( mangleGenericParams ) {}
-
-        Mangler::Mangler( const Mangler &rhs ) : mangleName() {
-                varNums = rhs.varNums;
-                nextVarNum = rhs.nextVarNum;
-                isTopLevel = rhs.isTopLevel;
-                mangleOverridable = rhs.mangleOverridable;
-                typeMode = rhs.typeMode;
-        }
-
-        void Mangler::mangleDecl( DeclarationWithType * declaration ) {
-                bool wasTopLevel = isTopLevel;
-                if ( isTopLevel ) {
-                        varNums.clear();
-                        nextVarNum = 0;
-                        isTopLevel = false;
-                } // if
-                mangleName << "__";
-                CodeGen::OperatorInfo opInfo;
-                if ( operatorLookup( declaration->get_name(), opInfo ) ) {
-                        mangleName << opInfo.outputName;
-                } else {
-                        mangleName << declaration->get_name();
-                } // if
-                mangleName << "__";
-                maybeAccept( declaration->get_type(), *this );
-                if ( mangleOverridable && LinkageSpec::isOverridable( declaration->get_linkage() ) ) {
-                        // want to be able to override autogenerated and intrinsic routines,
-                        // so they need a different name mangling
-                        if ( declaration->get_linkage() == LinkageSpec::AutoGen ) {
-                                mangleName << "autogen__";
-                        } else if ( declaration->get_linkage() == LinkageSpec::Intrinsic ) {
-                                mangleName << "intrinsic__";
-                        } else {
-                                // if we add another kind of overridable function, this has to change
-                                assert( false && "unknown overrideable linkage" );
-                        } // if
+        namespace Mangler {
+                namespace {
+                        /// Mangles names to a unique C identifier
+                        struct Mangler : public WithShortCircuiting, public WithVisitorRef<Mangler>, public WithGuards {
+                                Mangler( bool mangleOverridable, bool typeMode, bool mangleGenericParams );
+                                Mangler( const Mangler & ) = delete;
+
+                                void previsit( BaseSyntaxNode * ) { visit_children = false; }
+
+                                void postvisit( ObjectDecl * declaration );
+                                void postvisit( FunctionDecl * declaration );
+                                void postvisit( TypeDecl * declaration );
+
+                                void postvisit( VoidType * voidType );
+                                void postvisit( BasicType * basicType );
+                                void postvisit( PointerType * pointerType );
+                                void postvisit( ArrayType * arrayType );
+                                void postvisit( ReferenceType * refType );
+                                void postvisit( FunctionType * functionType );
+                                void postvisit( StructInstType * aggregateUseType );
+                                void postvisit( UnionInstType * aggregateUseType );
+                                void postvisit( EnumInstType * aggregateUseType );
+                                void postvisit( TypeInstType * aggregateUseType );
+                                void postvisit( TraitInstType * inst );
+                                void postvisit( TupleType * tupleType );
+                                void postvisit( VarArgsType * varArgsType );
+                                void postvisit( ZeroType * zeroType );
+                                void postvisit( OneType * oneType );
+                                void postvisit( QualifiedType * qualType );
+
+                                std::string get_mangleName() { return mangleName.str(); }
+                          private:
+                                std::ostringstream mangleName;  ///< Mangled name being constructed
+                                typedef std::map< std::string, std::pair< int, int > > VarMapType;
+                                VarMapType varNums;             ///< Map of type variables to indices
+                                int nextVarNum;                 ///< Next type variable index
+                                bool isTopLevel;                ///< Is the Mangler at the top level
+                                bool mangleOverridable;         ///< Specially mangle overridable built-in methods
+                                bool typeMode;                  ///< Produce a unique mangled name for a type
+                                bool mangleGenericParams;       ///< Include generic parameters in name mangling if true
+                                bool inFunctionType = false;    ///< Include type qualifiers if false.
+                                bool inQualifiedType = false;   ///< Add start/end delimiters around qualified type
+
+                                void mangleDecl( DeclarationWithType *declaration );
+                                void mangleRef( ReferenceToType *refType, std::string prefix );
+
+                                void printQualifiers( Type *type );
+                        }; // Mangler
+                } // namespace
+
+                std::string mangle( BaseSyntaxNode * decl, bool mangleOverridable, bool typeMode, bool mangleGenericParams ) {
+                        PassVisitor<Mangler> mangler( mangleOverridable, typeMode, mangleGenericParams );
+                        maybeAccept( decl, mangler );
+                        return mangler.pass.get_mangleName();
                 }
-                isTopLevel = wasTopLevel;
-        }
-
-        void Mangler::visit( ObjectDecl * declaration ) {
-                mangleDecl( declaration );
-        }
-
-        void Mangler::visit( FunctionDecl * declaration ) {
-                mangleDecl( declaration );
-        }
-
-        void Mangler::visit( VoidType * voidType ) {
-                printQualifiers( voidType );
-                mangleName << "v";
-        }
-
-        void Mangler::visit( BasicType * basicType ) {
-                static const char *btLetter[] = {
-                        "b",    // Bool
-                        "c",    // Char
-                        "Sc",   // SignedChar
-                        "Uc",   // UnsignedChar
-                        "s",    // ShortSignedInt
-                        "Us",   // ShortUnsignedInt
-                        "i",    // SignedInt
-                        "Ui",   // UnsignedInt
-                        "l",    // LongSignedInt
-                        "Ul",   // LongUnsignedInt
-                        "q",    // LongLongSignedInt
-                        "Uq",   // LongLongUnsignedInt
-                        "f",    // Float
-                        "d",    // Double
-                        "r",    // LongDouble
-                        "Xf",   // FloatComplex
-                        "Xd",   // DoubleComplex
-                        "Xr",   // LongDoubleComplex
-                        "If",   // FloatImaginary
-                        "Id",   // DoubleImaginary
-                        "Ir",   // LongDoubleImaginary
-                        "w",    // SignedInt128
-                        "Uw",   // UnsignedInt128
-                };
-
-                printQualifiers( basicType );
-                mangleName << btLetter[ basicType->get_kind() ];
-        }
-
-        void Mangler::visit( PointerType * pointerType ) {
-                printQualifiers( pointerType );
-                mangleName << "P";
-                maybeAccept( pointerType->get_base(), *this );
-        }
-
-        void Mangler::visit( ArrayType * arrayType ) {
-                // TODO: encode dimension
-                printQualifiers( arrayType );
-                mangleName << "A0";
-                maybeAccept( arrayType->get_base(), *this );
-        }
-
-        void Mangler::visit( ReferenceType * refType ) {
-                printQualifiers( refType );
-                mangleName << "R";
-                maybeAccept( refType->get_base(), *this );
-        }
-
-        namespace {
-                inline std::list< Type* > getTypes( const std::list< DeclarationWithType* > decls ) {
-                        std::list< Type* > ret;
-                        std::transform( decls.begin(), decls.end(), std::back_inserter( ret ),
-                                                        std::mem_fun( &DeclarationWithType::get_type ) );
-                        return ret;
+
+                std::string mangleType( Type * ty ) {
+                        PassVisitor<Mangler> mangler( false, true, true );
+                        maybeAccept( ty, mangler );
+                        return mangler.pass.get_mangleName();
                 }
-        }
-
-        void Mangler::visit( FunctionType * functionType ) {
-                printQualifiers( functionType );
-                mangleName << "F";
-                std::list< Type* > returnTypes = getTypes( functionType->get_returnVals() );
-                acceptAll( returnTypes, *this );
-                mangleName << "_";
-                std::list< Type* > paramTypes = getTypes( functionType->get_parameters() );
-                acceptAll( paramTypes, *this );
-                mangleName << "_";
-        }
-
-        void Mangler::mangleRef( ReferenceToType * refType, std::string prefix ) {
-                printQualifiers( refType );
-
-                mangleName << ( refType->get_name().length() + prefix.length() ) << prefix << refType->get_name();
-
-                if ( mangleGenericParams ) {
-                        std::list< Expression* >& params = refType->get_parameters();
-                        if ( ! params.empty() ) {
+
+                std::string mangleConcrete( Type * ty ) {
+                        PassVisitor<Mangler> mangler( false, false, false );
+                        maybeAccept( ty, mangler );
+                        return mangler.pass.get_mangleName();
+                }
+
+                namespace {
+                        Mangler::Mangler( bool mangleOverridable, bool typeMode, bool mangleGenericParams )
+                                : nextVarNum( 0 ), isTopLevel( true ), mangleOverridable( mangleOverridable ), typeMode( typeMode ), mangleGenericParams( mangleGenericParams ) {}
+
+                        void Mangler::mangleDecl( DeclarationWithType * declaration ) {
+                                bool wasTopLevel = isTopLevel;
+                                if ( isTopLevel ) {
+                                        varNums.clear();
+                                        nextVarNum = 0;
+                                        isTopLevel = false;
+                                } // if
+                                mangleName << Encoding::manglePrefix;
+                                CodeGen::OperatorInfo opInfo;
+                                if ( operatorLookup( declaration->get_name(), opInfo ) ) {
+                                        mangleName << opInfo.outputName.size() << opInfo.outputName;
+                                } else {
+                                        mangleName << declaration->name.size() << declaration->name;
+                                } // if
+                                maybeAccept( declaration->get_type(), *visitor );
+                                if ( mangleOverridable && LinkageSpec::isOverridable( declaration->get_linkage() ) ) {
+                                        // want to be able to override autogenerated and intrinsic routines,
+                                        // so they need a different name mangling
+                                        if ( declaration->get_linkage() == LinkageSpec::AutoGen ) {
+                                                mangleName << Encoding::autogen;
+                                        } else if ( declaration->get_linkage() == LinkageSpec::Intrinsic ) {
+                                                mangleName << Encoding::intrinsic;
+                                        } else {
+                                                // if we add another kind of overridable function, this has to change
+                                                assert( false && "unknown overrideable linkage" );
+                                        } // if
+                                }
+                                isTopLevel = wasTopLevel;
+                        }
+
+                        void Mangler::postvisit( ObjectDecl * declaration ) {
+                                mangleDecl( declaration );
+                        }
+
+                        void Mangler::postvisit( FunctionDecl * declaration ) {
+                                mangleDecl( declaration );
+                        }
+
+                        void Mangler::postvisit( VoidType * voidType ) {
+                                printQualifiers( voidType );
+                                mangleName << Encoding::void_t;
+                        }
+
+                        void Mangler::postvisit( BasicType * basicType ) {
+                                printQualifiers( basicType );
+                                assertf( basicType->get_kind() < BasicType::NUMBER_OF_BASIC_TYPES, "Unhandled basic type: %d", basicType->get_kind() );
+                                mangleName << Encoding::basicTypes[ basicType->get_kind() ];
+                        }
+
+                        void Mangler::postvisit( PointerType * pointerType ) {
+                                printQualifiers( pointerType );
+                                // mangle void (*f)() and void f() to the same name to prevent overloading on functions and function pointers
+                                if ( ! dynamic_cast<FunctionType *>( pointerType->base ) ) mangleName << Encoding::pointer;
+                                maybeAccept( pointerType->base, *visitor );
+                        }
+
+                        void Mangler::postvisit( ArrayType * arrayType ) {
+                                // TODO: encode dimension
+                                printQualifiers( arrayType );
+                                mangleName << Encoding::array << "0";
+                                maybeAccept( arrayType->base, *visitor );
+                        }
+
+                        void Mangler::postvisit( ReferenceType * refType ) {
+                                // don't print prefix (e.g. 'R') for reference types so that references and non-references do not overload.
+                                // Further, do not print the qualifiers for a reference type (but do run printQualifers because of TypeDecls, etc.),
+                                // by pretending every reference type is a function parameter.
+                                GuardValue( inFunctionType );
+                                inFunctionType = true;
+                                printQualifiers( refType );
+                                maybeAccept( refType->base, *visitor );
+                        }
+
+                        namespace {
+                                inline std::list< Type* > getTypes( const std::list< DeclarationWithType* > decls ) {
+                                        std::list< Type* > ret;
+                                        std::transform( decls.begin(), decls.end(), std::back_inserter( ret ),
+                                                                        std::mem_fun( &DeclarationWithType::get_type ) );
+                                        return ret;
+                                }
+                        }
+
+                        void Mangler::postvisit( FunctionType * functionType ) {
+                                printQualifiers( functionType );
+                                mangleName << Encoding::function;
+                                // turn on inFunctionType so that printQualifiers does not print most qualifiers for function parameters,
+                                // since qualifiers on outermost parameter type do not differentiate function types, e.g.,
+                                // void (*)(const int) and void (*)(int) are the same type, but void (*)(const int *) and void (*)(int *) are different
+                                GuardValue( inFunctionType );
+                                inFunctionType = true;
+                                std::list< Type* > returnTypes = getTypes( functionType->returnVals );
+                                if (returnTypes.empty()) mangleName << Encoding::void_t;
+                                else acceptAll( returnTypes, *visitor );
                                 mangleName << "_";
-                                for ( std::list< Expression* >::const_iterator param = params.begin(); param != params.end(); ++param ) {
-                                        TypeExpr *paramType = dynamic_cast< TypeExpr* >( *param );
-                                        assertf(paramType, "Aggregate parameters should be type expressions: %s", toString(*param).c_str());
-                                        maybeAccept( paramType->get_type(), *this );
-                                }
+                                std::list< Type* > paramTypes = getTypes( functionType->parameters );
+                                acceptAll( paramTypes, *visitor );
                                 mangleName << "_";
                         }
-                }
-        }
-
-        void Mangler::visit( StructInstType * aggregateUseType ) {
-                mangleRef( aggregateUseType, "s" );
-        }
-
-        void Mangler::visit( UnionInstType * aggregateUseType ) {
-                mangleRef( aggregateUseType, "u" );
-        }
-
-        void Mangler::visit( EnumInstType * aggregateUseType ) {
-                mangleRef( aggregateUseType, "e" );
-        }
-
-        void Mangler::visit( TypeInstType * typeInst ) {
-                VarMapType::iterator varNum = varNums.find( typeInst->get_name() );
-                if ( varNum == varNums.end() ) {
-                        mangleRef( typeInst, "t" );
-                } else {
-                        printQualifiers( typeInst );
-                        std::ostringstream numStream;
-                        numStream << varNum->second.first;
-                        switch ( (TypeDecl::Kind )varNum->second.second ) {
-                          case TypeDecl::Dtype:
-                                mangleName << "d";
-                                break;
-                          case TypeDecl::Ftype:
-                                mangleName << "f";
-                                break;
-                                case TypeDecl::Ttype:
-                                mangleName << "tVARGS";
-                                break;
-                                default:
-                                assert( false );
-                        } // switch
-                        mangleName << numStream.str();
-                } // if
-        }
-
-        void Mangler::visit( TupleType * tupleType ) {
-                printQualifiers( tupleType );
-                mangleName << "T";
-                acceptAll( tupleType->types, *this );
-                mangleName << "_";
-        }
-
-        void Mangler::visit( VarArgsType * varArgsType ) {
-                printQualifiers( varArgsType );
-                mangleName << "VARGS";
-        }
-
-        void Mangler::visit( ZeroType * ) {
-                mangleName << "Z";
-        }
-
-        void Mangler::visit( OneType * ) {
-                mangleName << "O";
-        }
-
-        void Mangler::visit( TypeDecl * decl ) {
-                static const char *typePrefix[] = { "BT", "BD", "BF" };
-                mangleName << typePrefix[ decl->get_kind() ] << ( decl->name.length() + 1 ) << decl->name;
-        }
-
-        void printVarMap( const std::map< std::string, std::pair< int, int > > &varMap, std::ostream &os ) {
-                for ( std::map< std::string, std::pair< int, int > >::const_iterator i = varMap.begin(); i != varMap.end(); ++i ) {
-                        os << i->first << "(" << i->second.first << "/" << i->second.second << ")" << std::endl;
-                } // for
-        }
-
-        void Mangler::printQualifiers( Type * type ) {
-                // skip if not including qualifiers
-                if ( typeMode ) return;
-
-                if ( ! type->get_forall().empty() ) {
-                        std::list< std::string > assertionNames;
-                        int tcount = 0, dcount = 0, fcount = 0, vcount = 0;
-                        mangleName << "A";
-                        for ( Type::ForallList::iterator i = type->forall.begin(); i != type->forall.end(); ++i ) {
-                                switch ( (*i)->get_kind() ) {
-                                  case TypeDecl::Dtype:
-                                        dcount++;
-                                        break;
-                                  case TypeDecl::Ftype:
-                                        fcount++;
-                                        break;
-                                  case TypeDecl::Ttype:
-                                        vcount++;
-                                        break;
-                                  default:
-                                        assert( false );
-                                } // switch
-                                varNums[ (*i)->name ] = std::pair< int, int >( nextVarNum++, (int)(*i)->get_kind() );
-                                for ( std::list< DeclarationWithType* >::iterator assert = (*i)->assertions.begin(); assert != (*i)->assertions.end(); ++assert ) {
-                                        Mangler sub_mangler( mangleOverridable, typeMode, mangleGenericParams );
-                                        sub_mangler.nextVarNum = nextVarNum;
-                                        sub_mangler.isTopLevel = false;
-                                        sub_mangler.varNums = varNums;
-                                        (*assert)->accept( sub_mangler );
-                                        assertionNames.push_back( sub_mangler.mangleName.str() );
+
+                        void Mangler::mangleRef( ReferenceToType * refType, std::string prefix ) {
+                                printQualifiers( refType );
+
+                                mangleName << prefix << refType->name.length() << refType->name;
+
+                                if ( mangleGenericParams ) {
+                                        std::list< Expression* >& params = refType->parameters;
+                                        if ( ! params.empty() ) {
+                                                mangleName << "_";
+                                                for ( std::list< Expression* >::const_iterator param = params.begin(); param != params.end(); ++param ) {
+                                                        TypeExpr *paramType = dynamic_cast< TypeExpr* >( *param );
+                                                        assertf(paramType, "Aggregate parameters should be type expressions: %s", toCString(*param));
+                                                        maybeAccept( paramType->type, *visitor );
+                                                }
+                                                mangleName << "_";
+                                        }
+                                }
+                        }
+
+                        void Mangler::postvisit( StructInstType * aggregateUseType ) {
+                                mangleRef( aggregateUseType, Encoding::struct_t );
+                        }
+
+                        void Mangler::postvisit( UnionInstType * aggregateUseType ) {
+                                mangleRef( aggregateUseType, Encoding::union_t );
+                        }
+
+                        void Mangler::postvisit( EnumInstType * aggregateUseType ) {
+                                mangleRef( aggregateUseType, Encoding::enum_t );
+                        }
+
+                        void Mangler::postvisit( TypeInstType * typeInst ) {
+                                VarMapType::iterator varNum = varNums.find( typeInst->get_name() );
+                                if ( varNum == varNums.end() ) {
+                                        mangleRef( typeInst, Encoding::type );
+                                } else {
+                                        printQualifiers( typeInst );
+                                        // Note: Can't use name here, since type variable names do not actually disambiguate a function, e.g.
+                                        //   forall(dtype T) void f(T);
+                                        //   forall(dtype S) void f(S);
+                                        // are equivalent and should mangle the same way. This is accomplished by numbering the type variables when they
+                                        // are first found and prefixing with the appropriate encoding for the type class.
+                                        assertf( varNum->second.second < TypeDecl::NUMBER_OF_KINDS, "Unhandled type variable kind: %d", varNum->second.second );
+                                        mangleName << Encoding::typeVariables[varNum->second.second] << varNum->second.first;
+                                } // if
+                        }
+
+                        void Mangler::postvisit( TraitInstType * inst ) {
+                                printQualifiers( inst );
+                                mangleName << inst->name.size() << inst->name;
+                        }
+
+                        void Mangler::postvisit( TupleType * tupleType ) {
+                                printQualifiers( tupleType );
+                                mangleName << Encoding::tuple << tupleType->types.size();
+                                acceptAll( tupleType->types, *visitor );
+                        }
+
+                        void Mangler::postvisit( VarArgsType * varArgsType ) {
+                                printQualifiers( varArgsType );
+                                static const std::string vargs = "__builtin_va_list";
+                                mangleName << Encoding::type << vargs.size() << vargs;
+                        }
+
+                        void Mangler::postvisit( ZeroType * ) {
+                                mangleName << Encoding::zero;
+                        }
+
+                        void Mangler::postvisit( OneType * ) {
+                                mangleName << Encoding::one;
+                        }
+
+                        void Mangler::postvisit( QualifiedType * qualType ) {
+                                bool inqual = inQualifiedType;
+                                if (! inqual ) {
+                                        // N marks the start of a qualified type
+                                        inQualifiedType = true;
+                                        mangleName << Encoding::qualifiedTypeStart;
+                                }
+                                maybeAccept( qualType->parent, *visitor );
+                                maybeAccept( qualType->child, *visitor );
+                                if ( ! inqual ) {
+                                        // E marks the end of a qualified type
+                                        inQualifiedType = false;
+                                        mangleName << Encoding::qualifiedTypeEnd;
+                                }
+                        }
+
+                        void Mangler::postvisit( TypeDecl * decl ) {
+                                // TODO: is there any case where mangling a TypeDecl makes sense? If so, this code needs to be
+                                // fixed to ensure that two TypeDecls mangle to the same name when they are the same type and vice versa.
+                                // Note: The current scheme may already work correctly for this case, I have not thought about this deeply
+                                // and the case has not yet come up in practice. Alternatively, if not then this code can be removed
+                                // aside from the assert false.
+                                assertf(false, "Mangler should not visit typedecl: %s", toCString(decl));
+                                assertf( decl->get_kind() < TypeDecl::NUMBER_OF_KINDS, "Unhandled type variable kind: %d", decl->get_kind() );
+                                mangleName << Encoding::typeVariables[ decl->get_kind() ] << ( decl->name.length() ) << decl->name;
+                        }
+
+                        __attribute__((unused)) void printVarMap( const std::map< std::string, std::pair< int, int > > &varMap, std::ostream &os ) {
+                                for ( std::map< std::string, std::pair< int, int > >::const_iterator i = varMap.begin(); i != varMap.end(); ++i ) {
+                                        os << i->first << "(" << i->second.first << "/" << i->second.second << ")" << std::endl;
                                 } // for
-                        } // for
-                        mangleName << tcount << "_" << dcount << "_" << fcount << "_" << vcount << "_";
-                        std::copy( assertionNames.begin(), assertionNames.end(), std::ostream_iterator< std::string >( mangleName, "" ) );
-                        mangleName << "_";
-                } // if
-                if ( type->get_const() ) {
-                        mangleName << "C";
-                } // if
-                if ( type->get_volatile() ) {
-                        mangleName << "V";
-                } // if
-                if ( type->get_mutex() ) {
-                        mangleName << "M";
-                } // if
-                // Removed due to restrict not affecting function compatibility in GCC
-//              if ( type->get_isRestrict() ) {
-//                      mangleName << "E";
-//              } // if
-                if ( type->get_lvalue() ) {
-                        // mangle based on whether the type is lvalue, so that the resolver can differentiate lvalues and rvalues
-                        mangleName << "L";
-                }
-                if ( type->get_atomic() ) {
-                        mangleName << "A";
-                } // if
-        }
+                        }
+
+                        void Mangler::printQualifiers( Type * type ) {
+                                // skip if not including qualifiers
+                                if ( typeMode ) return;
+                                if ( ! type->get_forall().empty() ) {
+                                        std::list< std::string > assertionNames;
+                                        int dcount = 0, fcount = 0, vcount = 0, acount = 0;
+                                        mangleName << Encoding::forall;
+                                        for ( Type::ForallList::iterator i = type->forall.begin(); i != type->forall.end(); ++i ) {
+                                                switch ( (*i)->get_kind() ) {
+                                                  case TypeDecl::Dtype:
+                                                        dcount++;
+                                                        break;
+                                                  case TypeDecl::Ftype:
+                                                        fcount++;
+                                                        break;
+                                                  case TypeDecl::Ttype:
+                                                        vcount++;
+                                                        break;
+                                                  default:
+                                                        assert( false );
+                                                } // switch
+                                                varNums[ (*i)->name ] = std::pair< int, int >( nextVarNum++, (int)(*i)->get_kind() );
+                                                for ( std::list< DeclarationWithType* >::iterator assert = (*i)->assertions.begin(); assert != (*i)->assertions.end(); ++assert ) {
+                                                        PassVisitor<Mangler> sub_mangler( mangleOverridable, typeMode, mangleGenericParams );
+                                                        sub_mangler.pass.nextVarNum = nextVarNum;
+                                                        sub_mangler.pass.isTopLevel = false;
+                                                        sub_mangler.pass.varNums = varNums;
+                                                        (*assert)->accept( sub_mangler );
+                                                        assertionNames.push_back( sub_mangler.pass.mangleName.str() );
+                                                        acount++;
+                                                } // for
+                                        } // for
+                                        mangleName << dcount << "_" << fcount << "_" << vcount << "_" << acount << "_";
+                                        std::copy( assertionNames.begin(), assertionNames.end(), std::ostream_iterator< std::string >( mangleName, "" ) );
+                                        mangleName << "_";
+                                } // if
+                                if ( ! inFunctionType ) {
+                                        // these qualifiers do not distinguish the outermost type of a function parameter
+                                        if ( type->get_const() ) {
+                                                mangleName << Encoding::qualifiers.at(Type::Const);
+                                        } // if
+                                        if ( type->get_volatile() ) {
+                                                mangleName << Encoding::qualifiers.at(Type::Volatile);
+                                        } // if
+                                        // Removed due to restrict not affecting function compatibility in GCC
+                                        // if ( type->get_isRestrict() ) {
+                                        //      mangleName << "E";
+                                        // } // if
+                                        if ( type->get_atomic() ) {
+                                                mangleName << Encoding::qualifiers.at(Type::Atomic);
+                                        } // if
+                                }
+                                if ( type->get_mutex() ) {
+                                        mangleName << Encoding::qualifiers.at(Type::Mutex);
+                                } // if
+                                if ( type->get_lvalue() ) {
+                                        // mangle based on whether the type is lvalue, so that the resolver can differentiate lvalues and rvalues
+                                        mangleName << Encoding::qualifiers.at(Type::Lvalue);
+                                }
+
+                                if ( inFunctionType ) {
+                                        // turn off inFunctionType so that types can be differentiated for nested qualifiers
+                                        GuardValue( inFunctionType );
+                                        inFunctionType = false;
+                                }
+                        }
+                }       // namespace
+        } // namespace Mangler
 } // namespace SymTab
 

src/SymTab/Mangler.h

@@ -24 +24 @@
 #include "SynTree/Visitor.h"  // for Visitor, maybeAccept
 
+// https://itanium-cxx-abi.github.io/cxx-abi/abi.html#mangling
+// The CFA name mangling scheme is based closely on the itanium C++ name mangling scheme, with the following key differences:
+// * Variable names are also mangled to include type information, not just functions
+// * CFA does not have template expansion, so the rules for function specialization do not apply.
+// * CFA instead has to handle type parameters and assertion parameters.
+// * Currently name compression is not implemented.
+
 namespace SymTab {
-        /// Mangles names to a unique C identifier
-        class Mangler : public Visitor {
-          public:
+        namespace Mangler {
                 /// Mangle syntax tree object; primary interface to clients
-                template< typename SynTreeClass >
-            static std::string mangle( SynTreeClass *decl, bool mangleOverridable = true, bool typeMode = false, bool mangleGenericParams = true );
+                std::string mangle( BaseSyntaxNode * decl, bool mangleOverridable = true, bool typeMode = false, bool mangleGenericParams = true );
+
                 /// Mangle a type name; secondary interface
-                static std::string mangleType( Type* ty );
+                std::string mangleType( Type* ty );
                 /// Mangle ignoring generic type parameters
-                static std::string mangleConcrete( Type* ty );
+                std::string mangleConcrete( Type* ty );
 
+                namespace Encoding {
+                        extern const std::string manglePrefix;
+                        extern const std::string basicTypes[];
+                        extern const std::map<int, std::string> qualifiers;
 
-                virtual void visit( ObjectDecl *declaration );
-                virtual void visit( FunctionDecl *declaration );
-                virtual void visit( TypeDecl *declaration );
+                        extern const std::string void_t;
+                        extern const std::string zero;
+                        extern const std::string one;
 
-                virtual void visit( VoidType *voidType );
-                virtual void visit( BasicType *basicType );
-                virtual void visit( PointerType *pointerType );
-                virtual void visit( ArrayType *arrayType );
-                virtual void visit( ReferenceType *refType );
-                virtual void visit( FunctionType *functionType );
-                virtual void visit( StructInstType *aggregateUseType );
-                virtual void visit( UnionInstType *aggregateUseType );
-                virtual void visit( EnumInstType *aggregateUseType );
-                virtual void visit( TypeInstType *aggregateUseType );
-                virtual void visit( TupleType *tupleType );
-                virtual void visit( VarArgsType *varArgsType );
-                virtual void visit( ZeroType *zeroType );
-                virtual void visit( OneType *oneType );
+                        extern const std::string function;
+                        extern const std::string tuple;
+                        extern const std::string pointer;
+                        extern const std::string array;
+                        extern const std::string qualifiedTypeStart;
+                        extern const std::string qualifiedTypeEnd;
 
-                std::string get_mangleName() { return mangleName.str(); }
-          private:
-                std::ostringstream mangleName;  ///< Mangled name being constructed
-                typedef std::map< std::string, std::pair< int, int > > VarMapType;
-                VarMapType varNums;             ///< Map of type variables to indices
-                int nextVarNum;                 ///< Next type variable index
-                bool isTopLevel;                ///< Is the Mangler at the top level
-                bool mangleOverridable;         ///< Specially mangle overridable built-in methods
-                bool typeMode;                  ///< Produce a unique mangled name for a type
-                bool mangleGenericParams;       ///< Include generic parameters in name mangling if true
+                        extern const std::string forall;
+                        extern const std::string typeVariables[];
 
-                Mangler( bool mangleOverridable, bool typeMode, bool mangleGenericParams );
-                Mangler( const Mangler & );
+                        extern const std::string struct_t;
+                        extern const std::string union_t;
+                        extern const std::string enum_t;
+                        extern const std::string type;
 
-                void mangleDecl( DeclarationWithType *declaration );
-                void mangleRef( ReferenceToType *refType, std::string prefix );
+                        extern const std::string autogen;
+                        extern const std::string intrinsic;
+                };
+        } // Mangler
+} // SymTab
 
-                void printQualifiers( Type *type );
-        }; // Mangler
-
-        template< typename SynTreeClass >
-        std::string Mangler::mangle( SynTreeClass *decl, bool mangleOverridable, bool typeMode, bool mangleGenericParams ) {
-                Mangler mangler( mangleOverridable, typeMode, mangleGenericParams );
-                maybeAccept( decl, mangler );
-                return mangler.get_mangleName();
-        }
-} // SymTab
+extern "C" {
+        char * cforall_demangle(const char *, int);
+}
 
 // Local Variables: //

src/SymTab/Validate.cc

@@ -48 +48 @@
 #include "CodeGen/CodeGenerator.h"     // for genName
 #include "CodeGen/OperatorTable.h"     // for isCtorDtor, isCtorDtorAssign
+#include "ControlStruct/Mutate.h"      // for ForExprMutator
 #include "Common/PassVisitor.h"        // for PassVisitor, WithDeclsToAdd
 #include "Common/ScopedMap.h"          // for ScopedMap
@@ -60 +61 @@
 #include "Parser/LinkageSpec.h"        // for C
 #include "ResolvExpr/typeops.h"        // for typesCompatible
-#include "SymTab/AddVisit.h"           // for addVisit
+#include "ResolvExpr/Resolver.h"       // for findSingleExpression
+#include "ResolvExpr/ResolveTypeof.h"  // for resolveTypeof
 #include "SymTab/Autogen.h"            // for SizeType
 #include "SynTree/Attribute.h"         // for noAttributes, Attribute
@@ -72 +74 @@
 #include "SynTree/TypeSubstitution.h"  // for TypeSubstitution
 #include "SynTree/Visitor.h"           // for Visitor
+#include "Validate/HandleAttributes.h" // for handleAttributes
 
 class CompoundStmt;
@@ -77 +80 @@
 class SwitchStmt;
 
-
-#define debugPrint( x ) if ( doDebug ) { std::cout << x; }
+#define debugPrint( x ) if ( doDebug ) x
 
 namespace SymTab {
+        /// hoists declarations that are difficult to hoist while parsing
+        struct HoistTypeDecls final : public WithDeclsToAdd {
+                void previsit( SizeofExpr * );
+                void previsit( AlignofExpr * );
+                void previsit( UntypedOffsetofExpr * );
+                void previsit( CompoundLiteralExpr * );
+                void handleType( Type * );
+        };
+
+        struct FixQualifiedTypes final : public WithIndexer {
+                Type * postmutate( QualifiedType * );
+        };
+
         struct HoistStruct final : public WithDeclsToAdd, public WithGuards {
                 /// Flattens nested struct types
                 static void hoistStruct( std::list< Declaration * > &translationUnit );
 
-                void previsit( EnumInstType * enumInstType );
-                void previsit( StructInstType * structInstType );
-                void previsit( UnionInstType * unionInstType );
                 void previsit( StructDecl * aggregateDecl );
                 void previsit( UnionDecl * aggregateDecl );
+                void previsit( StaticAssertDecl * assertDecl );
+                void previsit( StructInstType * type );
+                void previsit( UnionInstType * type );
+                void previsit( EnumInstType * type );
 
           private:
                 template< typename AggDecl > void handleAggregate( AggDecl *aggregateDecl );
 
-                bool inStruct = false;
+                AggregateDecl * parentAggr = nullptr;
         };
 
@@ -112 +128 @@
 
         /// Associates forward declarations of aggregates with their definitions
-        struct LinkReferenceToTypes final : public WithIndexer, public WithGuards {
+        struct LinkReferenceToTypes final : public WithIndexer, public WithGuards, public WithVisitorRef<LinkReferenceToTypes>, public WithShortCircuiting {
                 LinkReferenceToTypes( const Indexer *indexer );
                 void postvisit( TypeInstType *typeInst );
@@ -120 +136 @@
                 void postvisit( UnionInstType *unionInst );
                 void postvisit( TraitInstType *traitInst );
+                void previsit( QualifiedType * qualType );
+                void postvisit( QualifiedType * qualType );
 
                 void postvisit( EnumDecl *enumDecl );
@@ -148 +166 @@
                 void previsit( ObjectDecl * object );
                 void previsit( FunctionDecl * func );
+                void previsit( FunctionType * ftype );
                 void previsit( StructDecl * aggrDecl );
                 void previsit( UnionDecl * aggrDecl );
@@ -164 +183 @@
         };
 
-        struct EliminateTypedef final : public WithVisitorRef<EliminateTypedef>, public WithGuards {
-                EliminateTypedef() : scopeLevel( 0 ) {}
+        struct ReplaceTypedef final : public WithVisitorRef<ReplaceTypedef>, public WithGuards, public WithShortCircuiting, public WithDeclsToAdd {
+                ReplaceTypedef() : scopeLevel( 0 ) {}
                 /// Replaces typedefs by forward declarations
-                static void eliminateTypedef( std::list< Declaration * > &translationUnit );
-
+                static void replaceTypedef( std::list< Declaration * > &translationUnit );
+
+                void premutate( QualifiedType * );
+                Type * postmutate( QualifiedType * qualType );
                 Type * postmutate( TypeInstType * aggregateUseType );
                 Declaration * postmutate( TypedefDecl * typeDecl );
@@ -179 +200 @@
 
                 void premutate( CompoundStmt * compoundStmt );
-                CompoundStmt * postmutate( CompoundStmt * compoundStmt );
 
                 void premutate( StructDecl * structDecl );
-                Declaration * postmutate( StructDecl * structDecl );
                 void premutate( UnionDecl * unionDecl );
-                Declaration * postmutate( UnionDecl * unionDecl );
                 void premutate( EnumDecl * enumDecl );
-                Declaration * postmutate( EnumDecl * enumDecl );
-                Declaration * postmutate( TraitDecl * contextDecl );
+                void premutate( TraitDecl * );
 
                 void premutate( FunctionType * ftype );
@@ -193 +210 @@
           private:
                 template<typename AggDecl>
-                AggDecl *handleAggregate( AggDecl * aggDecl );
-
-                template<typename AggDecl>
                 void addImplicitTypedef( AggDecl * aggDecl );
+                template< typename AggDecl >
+                void handleAggregate( AggDecl * aggr );
 
                 typedef std::unique_ptr<TypedefDecl> TypedefDeclPtr;
                 typedef ScopedMap< std::string, std::pair< TypedefDeclPtr, int > > TypedefMap;
-                typedef std::map< std::string, TypeDecl * > TypeDeclMap;
+                typedef ScopedMap< std::string, TypeDecl * > TypeDeclMap;
                 TypedefMap typedefNames;
                 TypeDeclMap typedeclNames;
                 int scopeLevel;
                 bool inFunctionType = false;
+        };
+
+        struct EliminateTypedef {
+                /// removes TypedefDecls from the AST
+                static void eliminateTypedef( std::list< Declaration * > &translationUnit );
+
+                template<typename AggDecl>
+                void handleAggregate( AggDecl *aggregateDecl );
+
+                void previsit( StructDecl * aggregateDecl );
+                void previsit( UnionDecl * aggregateDecl );
+                void previsit( CompoundStmt * compoundStmt );
         };
 
@@ -222 +250 @@
         };
 
-        struct ArrayLength {
+        struct FixObjectType : public WithIndexer {
+                /// resolves typeof type in object, function, and type declarations
+                static void fix( std::list< Declaration * > & translationUnit );
+
+                void previsit( ObjectDecl * );
+                void previsit( FunctionDecl * );
+                void previsit( TypeDecl * );
+        };
+
+        struct ArrayLength : public WithIndexer {
                 /// for array types without an explicit length, compute the length and store it so that it
                 /// is known to the rest of the phases. For example,
@@ -233 +270 @@
 
                 void previsit( ObjectDecl * objDecl );
+                void previsit( ArrayType * arrayType );
         };
 
@@ -262 +300 @@
                 PassVisitor<FindSpecialDeclarations> finder;
                 PassVisitor<LabelAddressFixer> labelAddrFixer;
-
-                EliminateTypedef::eliminateTypedef( translationUnit );
-                HoistStruct::hoistStruct( translationUnit ); // must happen after EliminateTypedef, so that aggregate typedefs occur in the correct order
+                PassVisitor<HoistTypeDecls> hoistDecls;
+                PassVisitor<FixQualifiedTypes> fixQual;
+
+                acceptAll( translationUnit, hoistDecls );
+                ReplaceTypedef::replaceTypedef( translationUnit );
                 ReturnTypeFixer::fix( translationUnit ); // must happen before autogen
                 acceptAll( translationUnit, epc ); // must happen before VerifyCtorDtorAssign, because void return objects should not exist; before LinkReferenceToTypes because it is an indexer and needs correct types for mangling
                 acceptAll( translationUnit, lrt ); // must happen before autogen, because sized flag needs to propagate to generated functions
+                mutateAll( translationUnit, fixQual ); // must happen after LinkReferenceToTypes, because aggregate members are accessed
+                HoistStruct::hoistStruct( translationUnit ); // must happen after EliminateTypedef, so that aggregate typedefs occur in the correct order
+                EliminateTypedef::eliminateTypedef( translationUnit ); //
                 acceptAll( translationUnit, genericParams );  // check as early as possible - can't happen before LinkReferenceToTypes
                 VerifyCtorDtorAssign::verify( translationUnit );  // must happen before autogen, because autogen examines existing ctor/dtors
@@ -274 +317 @@
                 Concurrency::applyKeywords( translationUnit );
                 acceptAll( translationUnit, fpd ); // must happen before autogenerateRoutines, after Concurrency::applyKeywords because uniqueIds must be set on declaration before resolution
+                ControlStruct::hoistControlDecls( translationUnit );  // hoist initialization out of for statements; must happen before autogenerateRoutines
                 autogenerateRoutines( translationUnit ); // moved up, used to be below compoundLiteral - currently needs EnumAndPointerDecay
                 Concurrency::implementMutexFuncs( translationUnit );
                 Concurrency::implementThreadStarter( translationUnit );
                 mutateAll( translationUnit, compoundliteral );
+                ResolvExpr::resolveWithExprs( translationUnit ); // must happen before FixObjectType because user-code is resolved and may contain with variables
+                FixObjectType::fix( translationUnit );
                 ArrayLength::computeLength( translationUnit );
                 acceptAll( translationUnit, finder ); // xxx - remove this pass soon
                 mutateAll( translationUnit, labelAddrFixer );
+                Validate::handleAttributes( translationUnit );
         }
 
@@ -292 +339 @@
         }
 
+
+        void HoistTypeDecls::handleType( Type * type ) {
+                // some type declarations are buried in expressions and not easy to hoist during parsing; hoist them here
+                AggregateDecl * aggr = nullptr;
+                if ( StructInstType * inst = dynamic_cast< StructInstType * >( type ) ) {
+                        aggr = inst->baseStruct;
+                } else if ( UnionInstType * inst = dynamic_cast< UnionInstType * >( type ) ) {
+                        aggr = inst->baseUnion;
+                } else if ( EnumInstType * inst = dynamic_cast< EnumInstType * >( type ) ) {
+                        aggr = inst->baseEnum;
+                }
+                if ( aggr && aggr->body ) {
+                        declsToAddBefore.push_front( aggr );
+                }
+        }
+
+        void HoistTypeDecls::previsit( SizeofExpr * expr ) {
+                handleType( expr->type );
+        }
+
+        void HoistTypeDecls::previsit( AlignofExpr * expr ) {
+                handleType( expr->type );
+        }
+
+        void HoistTypeDecls::previsit( UntypedOffsetofExpr * expr ) {
+                handleType( expr->type );
+        }
+
+        void HoistTypeDecls::previsit( CompoundLiteralExpr * expr ) {
+                handleType( expr->result );
+        }
+
+
+        Type * FixQualifiedTypes::postmutate( QualifiedType * qualType ) {
+                Type * parent = qualType->parent;
+                Type * child = qualType->child;
+                if ( dynamic_cast< GlobalScopeType * >( qualType->parent ) ) {
+                        // .T => lookup T at global scope
+                        if ( TypeInstType * inst = dynamic_cast< TypeInstType * >( child ) ) {
+                                auto td = indexer.globalLookupType( inst->name );
+                                if ( ! td ) {
+                                        SemanticError( qualType->location, toString("Use of undefined global type ", inst->name) );
+                                }
+                                auto base = td->base;
+                                assert( base );
+                                Type * ret = base->clone();
+                                ret->get_qualifiers() = qualType->get_qualifiers();
+                                return ret;
+                        } else {
+                                // .T => T is not a type name
+                                assertf( false, "unhandled global qualified child type: %s", toCString(child) );
+                        }
+                } else {
+                        // S.T => S must be an aggregate type, find the declaration for T in S.
+                        AggregateDecl * aggr = nullptr;
+                        if ( StructInstType * inst = dynamic_cast< StructInstType * >( parent ) ) {
+                                aggr = inst->baseStruct;
+                        } else if ( UnionInstType * inst = dynamic_cast< UnionInstType * > ( parent ) ) {
+                                aggr = inst->baseUnion;
+                        } else {
+                                SemanticError( qualType->location, toString("Qualified type requires an aggregate on the left, but has: ", parent) );
+                        }
+                        assert( aggr ); // TODO: need to handle forward declarations
+                        for ( Declaration * member : aggr->members ) {
+                                if ( StructInstType * inst = dynamic_cast< StructInstType * >( child ) ) {
+                                        if ( StructDecl * aggr = dynamic_cast< StructDecl * >( member ) ) {
+                                                if ( aggr->name == inst->name ) {
+                                                        // TODO: is this case, and other non-TypeInstType cases, necessary?
+                                                        return new StructInstType( qualType->get_qualifiers(), aggr );
+                                                }
+                                        }
+                                } else if ( UnionInstType * inst = dynamic_cast< UnionInstType * >( child ) ) {
+                                        if ( UnionDecl * aggr = dynamic_cast< UnionDecl * > ( member ) ) {
+                                                if ( aggr->name == inst->name ) {
+                                                        return new UnionInstType( qualType->get_qualifiers(), aggr );
+                                                }
+                                        }
+                                } else if ( EnumInstType * inst = dynamic_cast< EnumInstType * >( child ) ) {
+                                        if ( EnumDecl * aggr = dynamic_cast< EnumDecl * > ( member ) ) {
+                                                if ( aggr->name == inst->name ) {
+                                                        return new EnumInstType( qualType->get_qualifiers(), aggr );
+                                                }
+                                        }
+                                } else if ( TypeInstType * inst = dynamic_cast< TypeInstType * >( child ) ) {
+                                        // name on the right is a typedef
+                                        if ( NamedTypeDecl * aggr = dynamic_cast< NamedTypeDecl * > ( member ) ) {
+                                                if ( aggr->name == inst->name ) {
+                                                        assert( aggr->base );
+                                                        Type * ret = aggr->base->clone();
+                                                        ret->get_qualifiers() = qualType->get_qualifiers();
+                                                        return ret;
+                                                }
+                                        }
+                                } else {
+                                        // S.T - S is not an aggregate => error
+                                        assertf( false, "unhandled qualified child type: %s", toCString(qualType) );
+                                }
+                        }
+                        // failed to find a satisfying definition of type
+                        SemanticError( qualType->location, toString("Undefined type in qualified type: ", qualType) );
+                }
+
+                // ... may want to link canonical SUE definition to each forward decl so that it becomes easier to lookup?
+        }
+
+
         void HoistStruct::hoistStruct( std::list< Declaration * > &translationUnit ) {
                 PassVisitor<HoistStruct> hoister;
@@ -297 +450 @@
         }
 
-        bool isStructOrUnion( Declaration *decl ) {
-                return dynamic_cast< StructDecl * >( decl ) || dynamic_cast< UnionDecl * >( decl );
+        bool shouldHoist( Declaration *decl ) {
+                return dynamic_cast< StructDecl * >( decl ) || dynamic_cast< UnionDecl * >( decl ) || dynamic_cast< StaticAssertDecl * >( decl );
+        }
+
+        namespace {
+                void qualifiedName( AggregateDecl * aggr, std::ostringstream & ss ) {
+                        if ( aggr->parent ) qualifiedName( aggr->parent, ss );
+                        ss << "__" << aggr->name;
+                }
+
+                // mangle nested type names using entire parent chain
+                std::string qualifiedName( AggregateDecl * aggr ) {
+                        std::ostringstream ss;
+                        qualifiedName( aggr, ss );
+                        return ss.str();
+                }
         }
 
         template< typename AggDecl >
         void HoistStruct::handleAggregate( AggDecl *aggregateDecl ) {
-                if ( inStruct ) {
+                if ( parentAggr ) {
+                        aggregateDecl->parent = parentAggr;
+                        aggregateDecl->name = qualifiedName( aggregateDecl );
                         // Add elements in stack order corresponding to nesting structure.
                         declsToAddBefore.push_front( aggregateDecl );
                 } else {
-                        GuardValue( inStruct );
-                        inStruct = true;
+                        GuardValue( parentAggr );
+                        parentAggr = aggregateDecl;
                 } // if
                 // Always remove the hoisted aggregate from the inner structure.
-                GuardAction( [aggregateDecl]() { filter( aggregateDecl->members, isStructOrUnion, false ); } );
-        }
-
-        void HoistStruct::previsit( EnumInstType * inst ) {
-                if ( inst->baseEnum ) {
-                        declsToAddBefore.push_front( inst->baseEnum );
-                }
-        }
-
-        void HoistStruct::previsit( StructInstType * inst ) {
-                if ( inst->baseStruct ) {
-                        declsToAddBefore.push_front( inst->baseStruct );
-                }
-        }
-
-        void HoistStruct::previsit( UnionInstType * inst ) {
-                if ( inst->baseUnion ) {
-                        declsToAddBefore.push_front( inst->baseUnion );
+                GuardAction( [aggregateDecl]() { filter( aggregateDecl->members, shouldHoist, false ); } );
+        }
+
+        void HoistStruct::previsit( StaticAssertDecl * assertDecl ) {
+                if ( parentAggr ) {
+                        declsToAddBefore.push_back( assertDecl );
                 }
         }
@@ -340 +497 @@
         }
 
+        void HoistStruct::previsit( StructInstType * type ) {
+                // need to reset type name after expanding to qualified name
+                assert( type->baseStruct );
+                type->name = type->baseStruct->name;
+        }
+
+        void HoistStruct::previsit( UnionInstType * type ) {
+                assert( type->baseUnion );
+                type->name = type->baseUnion->name;
+        }
+
+        void HoistStruct::previsit( EnumInstType * type ) {
+                assert( type->baseEnum );
+                type->name = type->baseEnum->name;
+        }
+
+
+        bool isTypedef( Declaration *decl ) {
+                return dynamic_cast< TypedefDecl * >( decl );
+        }
+
+        void EliminateTypedef::eliminateTypedef( std::list< Declaration * > &translationUnit ) {
+                PassVisitor<EliminateTypedef> eliminator;
+                acceptAll( translationUnit, eliminator );
+                filter( translationUnit, isTypedef, true );
+        }
+
+        template< typename AggDecl >
+        void EliminateTypedef::handleAggregate( AggDecl *aggregateDecl ) {
+                filter( aggregateDecl->members, isTypedef, true );
+        }
+
+        void EliminateTypedef::previsit( StructDecl * aggregateDecl ) {
+                handleAggregate( aggregateDecl );
+        }
+
+        void EliminateTypedef::previsit( UnionDecl * aggregateDecl ) {
+                handleAggregate( aggregateDecl );
+        }
+
+        void EliminateTypedef::previsit( CompoundStmt * compoundStmt ) {
+                // remove and delete decl stmts
+                filter( compoundStmt->kids, [](Statement * stmt) {
+                        if ( DeclStmt *declStmt = dynamic_cast< DeclStmt * >( stmt ) ) {
+                                if ( dynamic_cast< TypedefDecl * >( declStmt->decl ) ) {
+                                        return true;
+                                } // if
+                        } // if
+                        return false;
+                }, true);
+        }
+
         void EnumAndPointerDecay::previsit( EnumDecl *enumDecl ) {
                 // Set the type of each member of the enumeration to be EnumConstant
-                for ( std::list< Declaration * >::iterator i = enumDecl->get_members().begin(); i != enumDecl->get_members().end(); ++i ) {
+                for ( std::list< Declaration * >::iterator i = enumDecl->members.begin(); i != enumDecl->members.end(); ++i ) {
                         ObjectDecl * obj = dynamic_cast< ObjectDecl * >( *i );
                         assert( obj );
-                        obj->set_type( new EnumInstType( Type::Qualifiers( Type::Const ), enumDecl->get_name() ) );
+                        obj->set_type( new EnumInstType( Type::Qualifiers( Type::Const ), enumDecl->name ) );
                 } // for
         }
@@ -351 +560 @@
         namespace {
                 template< typename DWTList >
-                void fixFunctionList( DWTList & dwts, FunctionType * func ) {
-                        // the only case in which "void" is valid is where it is the only one in the list; then it should be removed
-                        // entirely. other fix ups are handled by the FixFunction class
-                        typedef typename DWTList::iterator DWTIterator;
-                        DWTIterator begin( dwts.begin() ), end( dwts.end() );
-                        if ( begin == end ) return;
-                        PassVisitor<FixFunction> fixer;
-                        DWTIterator i = begin;
-                        *i = (*i)->acceptMutator( fixer );
-                        if ( fixer.pass.isVoid ) {
-                                DWTIterator j = i;
-                                ++i;
-                                delete *j;
-                                dwts.erase( j );
-                                if ( i != end ) {
-                                        throw SemanticError( "invalid type void in function type ", func );
-                                } // if
-                        } else {
-                                ++i;
-                                for ( ; i != end; ++i ) {
-                                        PassVisitor<FixFunction> fixer;
-                                        *i = (*i)->acceptMutator( fixer );
-                                        if ( fixer.pass.isVoid ) {
-                                                throw SemanticError( "invalid type void in function type ", func );
-                                        } // if
-                                } // for
-                        } // if
+                void fixFunctionList( DWTList & dwts, bool isVarArgs, FunctionType * func ) {
+                        auto nvals = dwts.size();
+                        bool containsVoid = false;
+                        for ( auto & dwt : dwts ) {
+                                // fix each DWT and record whether a void was found
+                                containsVoid |= fixFunction( dwt );
+                        }
+
+                        // the only case in which "void" is valid is where it is the only one in the list
+                        if ( containsVoid && ( nvals > 1 || isVarArgs ) ) {
+                                SemanticError( func, "invalid type void in function type " );
+                        }
+
+                        // one void is the only thing in the list; remove it.
+                        if ( containsVoid ) {
+                                delete dwts.front();
+                                dwts.clear();
+                        }
                 }
         }
@@ -383 +583 @@
         void EnumAndPointerDecay::previsit( FunctionType *func ) {
                 // Fix up parameters and return types
-                fixFunctionList( func->get_parameters(), func );
-                fixFunctionList( func->get_returnVals(), func );
+                fixFunctionList( func->parameters, func->isVarArgs, func );
+                fixFunctionList( func->returnVals, false, func );
         }
 
@@ -396 +596 @@
 
         void LinkReferenceToTypes::postvisit( EnumInstType *enumInst ) {
-                EnumDecl *st = local_indexer->lookupEnum( enumInst->get_name() );
+                EnumDecl *st = local_indexer->lookupEnum( enumInst->name );
                 // it's not a semantic error if the enum is not found, just an implicit forward declaration
                 if ( st ) {
-                        //assert( ! enumInst->get_baseEnum() || enumInst->get_baseEnum()->get_members().empty() || ! st->get_members().empty() );
-                        enumInst->set_baseEnum( st );
-                } // if
-                if ( ! st || st->get_members().empty() ) {
+                        enumInst->baseEnum = st;
+                } // if
+                if ( ! st || ! st->body ) {
                         // use of forward declaration
-                        forwardEnums[ enumInst->get_name() ].push_back( enumInst );
+                        forwardEnums[ enumInst->name ].push_back( enumInst );
                 } // if
         }
@@ -411 +610 @@
                 for ( Expression * param : inst->parameters ) {
                         if ( ! dynamic_cast< TypeExpr * >( param ) ) {
-                                throw SemanticError( "Expression parameters for generic types are currently unsupported: ", inst );
+                                SemanticError( inst, "Expression parameters for generic types are currently unsupported: " );
                         }
                 }
@@ -417 +616 @@
 
         void LinkReferenceToTypes::postvisit( StructInstType *structInst ) {
-                StructDecl *st = local_indexer->lookupStruct( structInst->get_name() );
+                StructDecl *st = local_indexer->lookupStruct( structInst->name );
                 // it's not a semantic error if the struct is not found, just an implicit forward declaration
                 if ( st ) {
-                        //assert( ! structInst->get_baseStruct() || structInst->get_baseStruct()->get_members().empty() || ! st->get_members().empty() );
-                        structInst->set_baseStruct( st );
-                } // if
-                if ( ! st || st->get_members().empty() ) {
+                        structInst->baseStruct = st;
+                } // if
+                if ( ! st || ! st->body ) {
                         // use of forward declaration
-                        forwardStructs[ structInst->get_name() ].push_back( structInst );
+                        forwardStructs[ structInst->name ].push_back( structInst );
                 } // if
                 checkGenericParameters( structInst );
@@ -431 +629 @@
 
         void LinkReferenceToTypes::postvisit( UnionInstType *unionInst ) {
-                UnionDecl *un = local_indexer->lookupUnion( unionInst->get_name() );
+                UnionDecl *un = local_indexer->lookupUnion( unionInst->name );
                 // it's not a semantic error if the union is not found, just an implicit forward declaration
                 if ( un ) {
-                        unionInst->set_baseUnion( un );
-                } // if
-                if ( ! un || un->get_members().empty() ) {
+                        unionInst->baseUnion = un;
+                } // if
+                if ( ! un || ! un->body ) {
                         // use of forward declaration
-                        forwardUnions[ unionInst->get_name() ].push_back( unionInst );
+                        forwardUnions[ unionInst->name ].push_back( unionInst );
                 } // if
                 checkGenericParameters( unionInst );
+        }
+
+        void LinkReferenceToTypes::previsit( QualifiedType * ) {
+                visit_children = false;
+        }
+
+        void LinkReferenceToTypes::postvisit( QualifiedType * qualType ) {
+                // linking only makes sense for the 'oldest ancestor' of the qualified type
+                qualType->parent->accept( *visitor );
         }
 
@@ -451 +658 @@
                         DeclarationWithType * dwt2 = dynamic_cast<DeclarationWithType *>( d2 );
                         if ( dwt1 && dwt2 ) {
-                                if ( dwt1->get_name() == dwt2->get_name() && ResolvExpr::typesCompatible( dwt1->get_type(), dwt2->get_type(), SymTab::Indexer() ) ) {
+                                if ( dwt1->name == dwt2->name && ResolvExpr::typesCompatible( dwt1->get_type(), dwt2->get_type(), SymTab::Indexer() ) ) {
                                         // std::cerr << "=========== equal:" << std::endl;
                                         // std::cerr << "d1: " << d1 << std::endl;
@@ -476 +683 @@
         template< typename Iterator >
         void expandAssertions( TraitInstType * inst, Iterator out ) {
-                assertf( inst->baseTrait, "Trait instance not linked to base trait: %s", toString( inst ).c_str() );
+                assertf( inst->baseTrait, "Trait instance not linked to base trait: %s", toCString( inst ) );
                 std::list< DeclarationWithType * > asserts;
                 for ( Declaration * decl : inst->baseTrait->members ) {
@@ -511 +718 @@
                 TraitDecl *traitDecl = local_indexer->lookupTrait( traitInst->name );
                 if ( ! traitDecl ) {
-                        throw SemanticError( "use of undeclared trait " + traitInst->name );
-                } // if
-                if ( traitDecl->get_parameters().size() != traitInst->get_parameters().size() ) {
-                        throw SemanticError( "incorrect number of trait parameters: ", traitInst );
+                        SemanticError( traitInst->location, "use of undeclared trait " + traitInst->name );
+                } // if
+                if ( traitDecl->parameters.size() != traitInst->parameters.size() ) {
+                        SemanticError( traitInst, "incorrect number of trait parameters: " );
                 } // if
                 traitInst->baseTrait = traitDecl;
 
                 // need to carry over the 'sized' status of each decl in the instance
-                for ( auto p : group_iterate( traitDecl->get_parameters(), traitInst->get_parameters() ) ) {
+                for ( auto p : group_iterate( traitDecl->parameters, traitInst->parameters ) ) {
                         TypeExpr * expr = dynamic_cast< TypeExpr * >( std::get<1>(p) );
                         if ( ! expr ) {
-                                throw SemanticError( "Expression parameters for trait instances are currently unsupported: ", std::get<1>(p) );
+                                SemanticError( std::get<1>(p), "Expression parameters for trait instances are currently unsupported: " );
                         }
                         if ( TypeInstType * inst = dynamic_cast< TypeInstType * >( expr->get_type() ) ) {
                                 TypeDecl * formalDecl = std::get<0>(p);
-                                TypeDecl * instDecl = inst->get_baseType();
+                                TypeDecl * instDecl = inst->baseType;
                                 if ( formalDecl->get_sized() ) instDecl->set_sized( true );
                         }
@@ -535 +742 @@
         void LinkReferenceToTypes::postvisit( EnumDecl *enumDecl ) {
                 // visit enum members first so that the types of self-referencing members are updated properly
-                if ( ! enumDecl->get_members().empty() ) {
-                        ForwardEnumsType::iterator fwds = forwardEnums.find( enumDecl->get_name() );
+                if ( enumDecl->body ) {
+                        ForwardEnumsType::iterator fwds = forwardEnums.find( enumDecl->name );
                         if ( fwds != forwardEnums.end() ) {
                                 for ( std::list< EnumInstType * >::iterator inst = fwds->second.begin(); inst != fwds->second.end(); ++inst ) {
-                                        (*inst )->set_baseEnum( enumDecl );
+                                        (*inst)->baseEnum = enumDecl;
                                 } // for
                                 forwardEnums.erase( fwds );
                         } // if
+
+                        for ( Declaration * member : enumDecl->members ) {
+                                ObjectDecl * field = strict_dynamic_cast<ObjectDecl *>( member );
+                                if ( field->init ) {
+                                        // need to resolve enumerator initializers early so that other passes that determine if an expression is constexpr have the appropriate information.
+                                        SingleInit * init = strict_dynamic_cast<SingleInit *>( field->init );
+                                        ResolvExpr::findSingleExpression( init->value, new BasicType( Type::Qualifiers(), BasicType::SignedInt ), indexer );
+                                }
+                        }
                 } // if
         }
@@ -575 +791 @@
                 // visit struct members first so that the types of self-referencing members are updated properly
                 // xxx - need to ensure that type parameters match up between forward declarations and definition (most importantly, number of type parameters and their defaults)
-                if ( ! structDecl->get_members().empty() ) {
-                        ForwardStructsType::iterator fwds = forwardStructs.find( structDecl->get_name() );
+                if ( structDecl->body ) {
+                        ForwardStructsType::iterator fwds = forwardStructs.find( structDecl->name );
                         if ( fwds != forwardStructs.end() ) {
                                 for ( std::list< StructInstType * >::iterator inst = fwds->second.begin(); inst != fwds->second.end(); ++inst ) {
-                                        (*inst )->set_baseStruct( structDecl );
+                                        (*inst)->baseStruct = structDecl;
                                 } // for
                                 forwardStructs.erase( fwds );
@@ -587 +803 @@
 
         void LinkReferenceToTypes::postvisit( UnionDecl *unionDecl ) {
-                if ( ! unionDecl->get_members().empty() ) {
-                        ForwardUnionsType::iterator fwds = forwardUnions.find( unionDecl->get_name() );
+                if ( unionDecl->body ) {
+                        ForwardUnionsType::iterator fwds = forwardUnions.find( unionDecl->name );
                         if ( fwds != forwardUnions.end() ) {
                                 for ( std::list< UnionInstType * >::iterator inst = fwds->second.begin(); inst != fwds->second.end(); ++inst ) {
-                                        (*inst )->set_baseUnion( unionDecl );
+                                        (*inst)->baseUnion = unionDecl;
                                 } // for
                                 forwardUnions.erase( fwds );
@@ -601 +817 @@
                 // ensure generic parameter instances are renamed like the base type
                 if ( inGeneric && typeInst->baseType ) typeInst->name = typeInst->baseType->name;
-                if ( NamedTypeDecl *namedTypeDecl = local_indexer->lookupType( typeInst->get_name() ) ) {
+                if ( NamedTypeDecl *namedTypeDecl = local_indexer->lookupType( typeInst->name ) ) {
                         if ( TypeDecl *typeDecl = dynamic_cast< TypeDecl * >( namedTypeDecl ) ) {
                                 typeInst->set_isFtype( typeDecl->get_kind() == TypeDecl::Ftype );
@@ -626 +842 @@
                         // apply FixFunction to every assertion to check for invalid void type
                         for ( DeclarationWithType *& assertion : type->assertions ) {
-                                PassVisitor<FixFunction> fixer;
-                                assertion = assertion->acceptMutator( fixer );
-                                if ( fixer.pass.isVoid ) {
-                                        throw SemanticError( "invalid type void in assertion of function ", node );
+                                bool isVoid = fixFunction( assertion );
+                                if ( isVoid ) {
+                                        SemanticError( node, "invalid type void in assertion of function " );
                                 } // if
                         } // for
@@ -637 +852 @@
 
         void ForallPointerDecay::previsit( ObjectDecl *object ) {
-                forallFixer( object->type->forall, object );
-                if ( PointerType *pointer = dynamic_cast< PointerType * >( object->type ) ) {
-                        forallFixer( pointer->base->forall, object );
-                } // if
+                // ensure that operator names only apply to functions or function pointers
+                if ( CodeGen::isOperator( object->name ) && ! dynamic_cast< FunctionType * >( object->type->stripDeclarator() ) ) {
+                        SemanticError( object->location, toCString( "operator ", object->name.c_str(), " is not a function or function pointer." )  );
+                }
                 object->fixUniqueId();
         }
 
         void ForallPointerDecay::previsit( FunctionDecl *func ) {
-                forallFixer( func->type->forall, func );
                 func->fixUniqueId();
+        }
+
+        void ForallPointerDecay::previsit( FunctionType * ftype ) {
+                forallFixer( ftype->forall, ftype );
         }
 
@@ -673 +891 @@
                 // were cast to void.
                 if ( ! returnStmt->get_expr() && returnVals.size() != 0 ) {
-                        throw SemanticError( "Non-void function returns no values: " , returnStmt );
-                }
-        }
-
-
-        bool isTypedef( Declaration *decl ) {
-                return dynamic_cast< TypedefDecl * >( decl );
-        }
-
-        void EliminateTypedef::eliminateTypedef( std::list< Declaration * > &translationUnit ) {
-                PassVisitor<EliminateTypedef> eliminator;
+                        SemanticError( returnStmt, "Non-void function returns no values: " );
+                }
+        }
+
+
+        void ReplaceTypedef::replaceTypedef( std::list< Declaration * > &translationUnit ) {
+                PassVisitor<ReplaceTypedef> eliminator;
                 mutateAll( translationUnit, eliminator );
                 if ( eliminator.pass.typedefNames.count( "size_t" ) ) {
                         // grab and remember declaration of size_t
-                        SizeType = eliminator.pass.typedefNames["size_t"].first->get_base()->clone();
+                        SizeType = eliminator.pass.typedefNames["size_t"].first->base->clone();
                 } else {
                         // xxx - missing global typedef for size_t - default to long unsigned int, even though that may be wrong
@@ -693 +907 @@
                         SizeType = new BasicType( Type::Qualifiers(), BasicType::LongUnsignedInt );
                 }
-                filter( translationUnit, isTypedef, true );
-        }
-
-        Type * EliminateTypedef::postmutate( TypeInstType * typeInst ) {
+        }
+
+        void ReplaceTypedef::premutate( QualifiedType * ) {
+                visit_children = false;
+        }
+
+        Type * ReplaceTypedef::postmutate( QualifiedType * qualType ) {
+                // replacing typedefs only makes sense for the 'oldest ancestor' of the qualified type
+                qualType->parent = qualType->parent->acceptMutator( *visitor );
+                return qualType;
+        }
+
+        Type * ReplaceTypedef::postmutate( TypeInstType * typeInst ) {
                 // instances of typedef types will come here. If it is an instance
                 // of a typdef type, link the instance to its actual type.
-                TypedefMap::const_iterator def = typedefNames.find( typeInst->get_name() );
+                TypedefMap::const_iterator def = typedefNames.find( typeInst->name );
                 if ( def != typedefNames.end() ) {
                         Type *ret = def->second.first->base->clone();
+                        ret->location = typeInst->location;
                         ret->get_qualifiers() |= typeInst->get_qualifiers();
                         // attributes are not carried over from typedef to function parameters/return values
@@ -714 +938 @@
                                 ReferenceToType *rtt = dynamic_cast<ReferenceToType*>(ret);
                                 if ( ! rtt ) {
-                                        throw SemanticError("Cannot apply type parameters to base type of " + typeInst->name);
+                                        SemanticError( typeInst->location, "Cannot apply type parameters to base type of " + typeInst->name );
                                 }
-                                rtt->get_parameters().clear();
+                                rtt->parameters.clear();
                                 cloneAll( typeInst->parameters, rtt->parameters );
                                 mutateAll( rtt->parameters, *visitor );  // recursively fix typedefs on parameters
@@ -723 +947 @@
                         return ret;
                 } else {
-                        TypeDeclMap::const_iterator base = typedeclNames.find( typeInst->get_name() );
-                        assertf( base != typedeclNames.end(), "Cannot find typedecl name %s", typeInst->name.c_str() );
+                        TypeDeclMap::const_iterator base = typedeclNames.find( typeInst->name );
+                        if ( base == typedeclNames.end() ) {
+                                SemanticError( typeInst->location, toString("Use of undefined type ", typeInst->name) );
+                        }
                         typeInst->set_baseType( base->second );
-                } // if
-                return typeInst;
+                        return typeInst;
+                } // if
+                assert( false );
         }
 
@@ -744 +971 @@
         }
 
-        Declaration *EliminateTypedef::postmutate( TypedefDecl * tyDecl ) {
-                if ( typedefNames.count( tyDecl->get_name() ) == 1 && typedefNames[ tyDecl->get_name() ].second == scopeLevel ) {
+        Declaration * ReplaceTypedef::postmutate( TypedefDecl * tyDecl ) {
+                if ( typedefNames.count( tyDecl->name ) == 1 && typedefNames[ tyDecl->name ].second == scopeLevel ) {
                         // typedef to the same name from the same scope
                         // must be from the same type
 
-                        Type * t1 = tyDecl->get_base();
-                        Type * t2 = typedefNames[ tyDecl->get_name() ].first->get_base();
+                        Type * t1 = tyDecl->base;
+                        Type * t2 = typedefNames[ tyDecl->name ].first->base;
                         if ( ! ResolvExpr::typesCompatible( t1, t2, Indexer() ) ) {
-                                throw SemanticError( "Cannot redefine typedef: " + tyDecl->name );
-                        }
-                        // cannot redefine VLA typedefs
+                                SemanticError( tyDecl->location, "Cannot redefine typedef: " + tyDecl->name );
+                        }
+                        // Cannot redefine VLA typedefs. Note: this is slightly incorrect, because our notion of VLAs
+                        // at this point in the translator is imprecise. In particular, this will disallow redefining typedefs
+                        // with arrays whose dimension is an enumerator or a cast of a constant/enumerator. The effort required
+                        // to fix this corner case likely outweighs the utility of allowing it.
                         if ( isVariableLength( t1 ) || isVariableLength( t2 ) ) {
-                                throw SemanticError( "Cannot redefine typedef: " + tyDecl->name );
+                                SemanticError( tyDecl->location, "Cannot redefine typedef: " + tyDecl->name );
                         }
                 } else {
-                        typedefNames[ tyDecl->get_name() ] = std::make_pair( TypedefDeclPtr( tyDecl ), scopeLevel );
+                        typedefNames[ tyDecl->name ] = std::make_pair( TypedefDeclPtr( tyDecl ), scopeLevel );
                 } // if
 
@@ -771 +1001 @@
                 // Note, qualifiers on the typedef are superfluous for the forward declaration.
 
-                Type *designatorType = tyDecl->get_base()->stripDeclarator();
+                Type *designatorType = tyDecl->base->stripDeclarator();
                 if ( StructInstType *aggDecl = dynamic_cast< StructInstType * >( designatorType ) ) {
-                        return new StructDecl( aggDecl->get_name(), DeclarationNode::Struct, noAttributes, tyDecl->get_linkage() );
+                        declsToAddBefore.push_back( new StructDecl( aggDecl->name, DeclarationNode::Struct, noAttributes, tyDecl->linkage ) );
                 } else if ( UnionInstType *aggDecl = dynamic_cast< UnionInstType * >( designatorType ) ) {
-                        return new UnionDecl( aggDecl->get_name(), noAttributes, tyDecl->get_linkage() );
+                        declsToAddBefore.push_back( new UnionDecl( aggDecl->name, noAttributes, tyDecl->linkage ) );
                 } else if ( EnumInstType *enumDecl = dynamic_cast< EnumInstType * >( designatorType ) ) {
-                        return new EnumDecl( enumDecl->get_name(), noAttributes, tyDecl->get_linkage() );
-                } else {
-                        return tyDecl->clone();
-                } // if
-        }
-
-        void EliminateTypedef::premutate( TypeDecl * typeDecl ) {
-                TypedefMap::iterator i = typedefNames.find( typeDecl->get_name() );
+                        declsToAddBefore.push_back( new EnumDecl( enumDecl->name, noAttributes, tyDecl->linkage ) );
+                } // if
+                return tyDecl->clone();
+        }
+
+        void ReplaceTypedef::premutate( TypeDecl * typeDecl ) {
+                TypedefMap::iterator i = typedefNames.find( typeDecl->name );
                 if ( i != typedefNames.end() ) {
                         typedefNames.erase( i ) ;
                 } // if
 
-                typedeclNames[ typeDecl->get_name() ] = typeDecl;
-        }
-
-        void EliminateTypedef::premutate( FunctionDecl * ) {
+                typedeclNames.insert( typeDecl->name, typeDecl );
+        }
+
+        void ReplaceTypedef::premutate( FunctionDecl * ) {
                 GuardScope( typedefNames );
-        }
-
-        void EliminateTypedef::premutate( ObjectDecl * ) {
+                GuardScope( typedeclNames );
+        }
+
+        void ReplaceTypedef::premutate( ObjectDecl * ) {
                 GuardScope( typedefNames );
-        }
-
-        DeclarationWithType *EliminateTypedef::postmutate( ObjectDecl * objDecl ) {
-                if ( FunctionType *funtype = dynamic_cast<FunctionType *>( objDecl->get_type() ) ) { // function type?
+                GuardScope( typedeclNames );
+        }
+
+        DeclarationWithType * ReplaceTypedef::postmutate( ObjectDecl * objDecl ) {
+                if ( FunctionType *funtype = dynamic_cast<FunctionType *>( objDecl->type ) ) { // function type?
                         // replace the current object declaration with a function declaration
-                        FunctionDecl * newDecl = new FunctionDecl( objDecl->get_name(), objDecl->get_storageClasses(), objDecl->get_linkage(), funtype, 0, objDecl->get_attributes(), objDecl->get_funcSpec() );
-                        objDecl->get_attributes().clear();
+                        FunctionDecl * newDecl = new FunctionDecl( objDecl->name, objDecl->get_storageClasses(), objDecl->linkage, funtype, 0, objDecl->attributes, objDecl->get_funcSpec() );
+                        objDecl->attributes.clear();
                         objDecl->set_type( nullptr );
                         delete objDecl;
@@ -812 +1043 @@
         }
 
-        void EliminateTypedef::premutate( CastExpr * ) {
+        void ReplaceTypedef::premutate( CastExpr * ) {
                 GuardScope( typedefNames );
-        }
-
-        void EliminateTypedef::premutate( CompoundStmt * ) {
+                GuardScope( typedeclNames );
+        }
+
+        void ReplaceTypedef::premutate( CompoundStmt * ) {
                 GuardScope( typedefNames );
+                GuardScope( typedeclNames );
                 scopeLevel += 1;
                 GuardAction( [this](){ scopeLevel -= 1; } );
         }
 
-        CompoundStmt *EliminateTypedef::postmutate( CompoundStmt * compoundStmt ) {
-                // remove and delete decl stmts
-                filter( compoundStmt->kids, [](Statement * stmt) {
-                        if ( DeclStmt *declStmt = dynamic_cast< DeclStmt * >( stmt ) ) {
-                                if ( dynamic_cast< TypedefDecl * >( declStmt->get_decl() ) ) {
-                                        return true;
-                                } // if
-                        } // if
-                        return false;
-                }, true);
-                return compoundStmt;
-        }
-
-        // there may be typedefs nested within aggregates. in order for everything to work properly, these should be removed
-        // as well
         template<typename AggDecl>
-        AggDecl *EliminateTypedef::handleAggregate( AggDecl * aggDecl ) {
-                filter( aggDecl->members, isTypedef, true );
-                return aggDecl;
-        }
-
-        template<typename AggDecl>
-        void EliminateTypedef::addImplicitTypedef( AggDecl * aggDecl ) {
+        void ReplaceTypedef::addImplicitTypedef( AggDecl * aggDecl ) {
                 if ( typedefNames.count( aggDecl->get_name() ) == 0 ) {
                         Type *type = nullptr;
@@ -854 +1066 @@
                                 type = new EnumInstType( Type::Qualifiers(), newDeclEnumDecl->get_name() );
                         } // if
-                        TypedefDeclPtr tyDecl( new TypedefDecl( aggDecl->get_name(), Type::StorageClasses(), type, aggDecl->get_linkage() ) );
+                        TypedefDeclPtr tyDecl( new TypedefDecl( aggDecl->get_name(), aggDecl->location, Type::StorageClasses(), type, aggDecl->get_linkage() ) );
                         typedefNames[ aggDecl->get_name() ] = std::make_pair( std::move( tyDecl ), scopeLevel );
-                } // if
-        }
-
-        void EliminateTypedef::premutate( StructDecl * structDecl ) {
+                        // add the implicit typedef to the AST
+                        declsToAddBefore.push_back( new TypedefDecl( aggDecl->get_name(), aggDecl->location, Type::StorageClasses(), type->clone(), aggDecl->get_linkage() ) );
+                } // if
+        }
+
+        template< typename AggDecl >
+        void ReplaceTypedef::handleAggregate( AggDecl * aggr ) {
+                SemanticErrorException errors;
+
+                ValueGuard< std::list<Declaration * > > oldBeforeDecls( declsToAddBefore );
+                ValueGuard< std::list<Declaration * > > oldAfterDecls ( declsToAddAfter  );
+                declsToAddBefore.clear();
+                declsToAddAfter.clear();
+
+                GuardScope( typedefNames );
+                GuardScope( typedeclNames );
+                mutateAll( aggr->parameters, *visitor );
+
+                // unroll mutateAll for aggr->members so that implicit typedefs for nested types are added to the aggregate body.
+                for ( std::list< Declaration * >::iterator i = aggr->members.begin(); i != aggr->members.end(); ++i ) {
+                        if ( !declsToAddAfter.empty() ) { aggr->members.splice( i, declsToAddAfter ); }
+
+                        try {
+                                *i = maybeMutate( *i, *visitor );
+                        } catch ( SemanticErrorException &e ) {
+                                errors.append( e );
+                        }
+
+                        if ( !declsToAddBefore.empty() ) { aggr->members.splice( i, declsToAddBefore ); }
+                }
+
+                if ( !declsToAddAfter.empty() ) { aggr->members.splice( aggr->members.end(), declsToAddAfter ); }
+                if ( !errors.isEmpty() ) { throw errors; }
+        }
+
+        void ReplaceTypedef::premutate( StructDecl * structDecl ) {
+                visit_children = false;
                 addImplicitTypedef( structDecl );
-        }
-
-
-        Declaration *EliminateTypedef::postmutate( StructDecl * structDecl ) {
-                return handleAggregate( structDecl );
-        }
-
-        void EliminateTypedef::premutate( UnionDecl * unionDecl ) {
+                handleAggregate( structDecl );
+        }
+
+        void ReplaceTypedef::premutate( UnionDecl * unionDecl ) {
+                visit_children = false;
                 addImplicitTypedef( unionDecl );
-        }
-
-        Declaration *EliminateTypedef::postmutate( UnionDecl * unionDecl ) {
-                return handleAggregate( unionDecl );
-        }
-
-        void EliminateTypedef::premutate( EnumDecl * enumDecl ) {
+                handleAggregate( unionDecl );
+        }
+
+        void ReplaceTypedef::premutate( EnumDecl * enumDecl ) {
                 addImplicitTypedef( enumDecl );
         }
 
-        Declaration *EliminateTypedef::postmutate( EnumDecl * enumDecl ) {
-                return handleAggregate( enumDecl );
-        }
-
-        Declaration *EliminateTypedef::postmutate( TraitDecl * traitDecl ) {
-                return handleAggregate( traitDecl );
-        }
-
-        void EliminateTypedef::premutate( FunctionType * ) {
+        void ReplaceTypedef::premutate( FunctionType * ) {
                 GuardValue( inFunctionType );
                 inFunctionType = true;
+        }
+
+        void ReplaceTypedef::premutate( TraitDecl * ) {
+                GuardScope( typedefNames );
+                GuardScope( typedeclNames);
         }
 
@@ -905 +1141 @@
                 if ( CodeGen::isCtorDtorAssign( funcDecl->get_name() ) ) { // TODO: also check /=, etc.
                         if ( params.size() == 0 ) {
-                                throw SemanticError( "Constructors, destructors, and assignment functions require at least one parameter ", funcDecl );
+                                SemanticError( funcDecl, "Constructors, destructors, and assignment functions require at least one parameter " );
                         }
                         ReferenceType * refType = dynamic_cast< ReferenceType * >( params.front()->get_type() );
                         if ( ! refType ) {
-                                throw SemanticError( "First parameter of a constructor, destructor, or assignment function must be a reference ", funcDecl );
+                                SemanticError( funcDecl, "First parameter of a constructor, destructor, or assignment function must be a reference " );
                         }
                         if ( CodeGen::isCtorDtor( funcDecl->get_name() ) && returnVals.size() != 0 ) {
-                                throw SemanticError( "Constructors and destructors cannot have explicit return values ", funcDecl );
+                                SemanticError( funcDecl, "Constructors and destructors cannot have explicit return values " );
                         }
                 }
@@ -947 +1183 @@
 
                         sub.apply( inst );
-                        if ( args.size() < params->size() ) throw SemanticError( "Too few type arguments in generic type ", inst );
-                        if ( args.size() > params->size() ) throw SemanticError( "Too many type arguments in generic type ", inst );
+                        if ( args.size() < params->size() ) SemanticError( inst, "Too few type arguments in generic type " );
+                        if ( args.size() > params->size() ) SemanticError( inst, "Too many type arguments in generic type " );
                 }
         }
@@ -1014 +1250 @@
         }
 
+        void FixObjectType::fix( std::list< Declaration * > & translationUnit ) {
+                PassVisitor<FixObjectType> fixer;
+                acceptAll( translationUnit, fixer );
+        }
+
+        void FixObjectType::previsit( ObjectDecl * objDecl ) {
+                Type *new_type = ResolvExpr::resolveTypeof( objDecl->get_type(), indexer );
+                new_type->get_qualifiers() -= Type::Lvalue; // even if typeof is lvalue, variable can never have lvalue-qualified type
+                objDecl->set_type( new_type );
+        }
+
+        void FixObjectType::previsit( FunctionDecl * funcDecl ) {
+                Type *new_type = ResolvExpr::resolveTypeof( funcDecl->type, indexer );
+                new_type->get_qualifiers() -= Type::Lvalue; // even if typeof is lvalue, variable can never have lvalue-qualified type
+                funcDecl->set_type( new_type );
+        }
+
+        void FixObjectType::previsit( TypeDecl *typeDecl ) {
+                if ( typeDecl->get_base() ) {
+                        Type *new_type = ResolvExpr::resolveTypeof( typeDecl->get_base(), indexer );
+                        new_type->get_qualifiers() -= Type::Lvalue; // even if typeof is lvalue, variable can never have lvalue-qualified type
+                        typeDecl->set_base( new_type );
+                } // if
+        }
+
         void ArrayLength::computeLength( std::list< Declaration * > & translationUnit ) {
                 PassVisitor<ArrayLength> len;
@@ -1020 +1281 @@
 
         void ArrayLength::previsit( ObjectDecl * objDecl ) {
-                if ( ArrayType * at = dynamic_cast< ArrayType * >( objDecl->get_type() ) ) {
-                        if ( at->get_dimension() ) return;
-                        if ( ListInit * init = dynamic_cast< ListInit * >( objDecl->get_init() ) ) {
-                                at->set_dimension( new ConstantExpr( Constant::from_ulong( init->get_initializers().size() ) ) );
-                        }
+                if ( ArrayType * at = dynamic_cast< ArrayType * >( objDecl->type ) ) {
+                        if ( at->dimension ) return;
+                        if ( ListInit * init = dynamic_cast< ListInit * >( objDecl->init ) ) {
+                                at->dimension = new ConstantExpr( Constant::from_ulong( init->initializers.size() ) );
+                        }
+                }
+        }
+
+        void ArrayLength::previsit( ArrayType * type ) {
+                if ( type->dimension ) {
+                        // need to resolve array dimensions early so that constructor code can correctly determine
+                        // if a type is a VLA (and hence whether its elements need to be constructed)
+                        ResolvExpr::findSingleExpression( type->dimension, SymTab::SizeType->clone(), indexer );
+
+                        // must re-evaluate whether a type is a VLA, now that more information is available
+                        // (e.g. the dimension may have been an enumerator, which was unknown prior to this step)
+                        type->isVarLen = ! InitTweak::isConstExpr( type->dimension );
                 }
         }

src/SymTab/module.mk

@@ -17 +17 @@
 SRC += SymTab/Indexer.cc \
        SymTab/Mangler.cc \
+       SymTab/ManglerCommon.cc \
        SymTab/Validate.cc \
        SymTab/FixFunction.cc \