Changeset bbeb908 for src/ResolvExpr/PtrsAssignable.cc

Timestamp:

Nov 6, 2017, 11:11:56 AM (6 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, aaron-thesis, arm-eh, ast-experimental, cleanup-dtors, deferred_resn, demangler, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, new-env, no_list, persistent-indexer, pthread-emulation, qualifiedEnum, resolv-new, with_gc

Children:

a2ea829

Parents:

e706bfd (diff), 121ac13 (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' of plg.uwaterloo.ca:software/cfa/cfa-cc

File:

• src/ResolvExpr/PtrsAssignable.cc (modified) (6 diffs)

src/ResolvExpr/PtrsAssignable.cc

@@ -47 +47 @@
 
         int ptrsAssignable( Type *src, Type *dest, const TypeEnvironment &env ) {
+                // std::cerr << "assignable: " << src << " | " << dest << std::endl;
                 if ( TypeInstType *destAsTypeInst = dynamic_cast< TypeInstType* >( dest ) ) {
                         EqvClass eqvClass;
@@ -54 +55 @@
                 } // if
                 if ( dynamic_cast< VoidType* >( dest ) ) {
-                        return 1;
+                        // void * = T * for any T is unsafe
+                        // xxx - this should be safe, but that currently breaks the build
+                        return -1;
                 } else {
                         PtrsAssignable ptrs( dest, env );
@@ -65 +68 @@
 
         void PtrsAssignable::visit( __attribute((unused)) VoidType *voidType ) {
-                if ( dynamic_cast< FunctionType* >( dest ) ) {
-                        result = 0;
-                } else {
-                        result = -1;
+                if ( ! dynamic_cast< FunctionType* >( dest ) ) {
+                        // T * = void * is safe for any T that is not a function type.
+                        // xxx - this should be unsafe...
+                        result = 1;
                 } // if
         }
@@ -75 +78 @@
         void PtrsAssignable::visit( __attribute__((unused)) PointerType *pointerType ) {}
         void PtrsAssignable::visit( __attribute__((unused)) ArrayType *arrayType ) {}
-        void PtrsAssignable::visit( __attribute__((unused)) FunctionType *functionType ) {
-                result = -1;
-        }
+        void PtrsAssignable::visit( __attribute__((unused)) FunctionType *functionType ) {}
 
         void PtrsAssignable::visit(  __attribute__((unused)) StructInstType *inst ) {}
@@ -83 +84 @@
 
         void PtrsAssignable::visit( EnumInstType * ) {
-                if ( dynamic_cast< EnumInstType* >( dest ) ) {
+                if ( dynamic_cast< BasicType* >( dest ) ) {
+                        // int * = E *, etc. is safe. This isn't technically correct, as each
+                        // enum has one basic type that it is compatible with, an that type can
+                        // differ from enum to enum. Without replicating GCC's internal logic,
+                        // there is no way to know which type this particular enum is compatible
+                        // with, so punt on this for now.
                         result = 1;
-                } else if ( BasicType *bt = dynamic_cast< BasicType* >( dest ) ) {
-                        result = bt->get_kind() == BasicType::SignedInt;
                 }
         }
@@ -94 +98 @@
                 EqvClass eqvClass;
                 if ( env.lookup( inst->get_name(), eqvClass ) && eqvClass.type ) {
+                        // T * = S * for any S depends on the type bound to T
                         result = ptrsAssignable( eqvClass.type, dest, env );
-                } else {
-                        result = 0;
                 } // if
         }