Index: src/CodeGen/CodeGenerator.cc
===================================================================
--- src/CodeGen/CodeGenerator.cc	(revision 61f9356c5a7f6b519ed835460f72dc5f34708073)
+++ src/CodeGen/CodeGenerator.cc	(revision 803deb12902ca2c3780803d39417a86c02b8ba33)
@@ -5,11 +5,11 @@
 // file "LICENCE" distributed with Cforall.
 //
-// CodeGenerator.cc -- 
+// CodeGenerator.cc --
 //
 // Author           : Richard C. Bilson
 // Created On       : Mon May 18 07:44:20 2015
 // Last Modified By : Rob Schluntz
-// Last Modified On : Thu Sep 17 15:24:08 2015
-// Update Count     : 231
+// Last Modified On : Wed Jan 20 12:54:50 2016
+// Update Count     : 241
 //
 
@@ -98,5 +98,5 @@
 		handleStorageClass( objectDecl );
 		output << genType( objectDecl->get_type(), mangleName( objectDecl ) );
-	
+
 		if ( objectDecl->get_init() ) {
 			output << " = ";
@@ -112,5 +112,5 @@
 		if ( aggDecl->get_name() != "" )
 			output << aggDecl->get_name();
-	
+
 		std::list< Declaration * > &memb = aggDecl->get_members();
 
@@ -118,12 +118,12 @@
 			output << " {" << endl;
 
-			cur_indent += CodeGenerator::tabsize; 
+			cur_indent += CodeGenerator::tabsize;
 			for ( std::list< Declaration* >::iterator i = memb.begin(); i != memb.end();  i++) {
-				output << indent; 
+				output << indent;
 				(*i)->accept( *this );
 				output << ";" << endl;
 			}
 
-			cur_indent -= CodeGenerator::tabsize; 
+			cur_indent -= CodeGenerator::tabsize;
 
 			output << indent << "}";
@@ -140,5 +140,5 @@
 		handleAggregate( aggregateDecl );
 	}
-  
+
 	void CodeGenerator::visit( EnumDecl *aggDecl ) {
 		output << "enum ";
@@ -146,5 +146,5 @@
 		if ( aggDecl->get_name() != "" )
 			output << aggDecl->get_name();
-	
+
 		std::list< Declaration* > &memb = aggDecl->get_members();
 
@@ -152,9 +152,9 @@
 			output << " {" << endl;
 
-			cur_indent += CodeGenerator::tabsize; 
+			cur_indent += CodeGenerator::tabsize;
 			for ( std::list< Declaration* >::iterator i = memb.begin(); i != memb.end();  i++) {
 				ObjectDecl *obj = dynamic_cast< ObjectDecl* >( *i );
 				assert( obj );
-				output << indent << mangleName( obj ); 
+				output << indent << mangleName( obj );
 				if ( obj->get_init() ) {
 					output << " = ";
@@ -164,17 +164,17 @@
 			} // for
 
-			cur_indent -= CodeGenerator::tabsize; 
+			cur_indent -= CodeGenerator::tabsize;
 
 			output << indent << "}";
 		} // if
 	}
-  
+
 	void CodeGenerator::visit( ContextDecl *aggregateDecl ) {}
-  
+
 	void CodeGenerator::visit( TypedefDecl *typeDecl ) {
 		output << "typedef ";
 		output << genType( typeDecl->get_base(), typeDecl->get_name() );
 	}
-  
+
 	void CodeGenerator::visit( TypeDecl *typeDecl ) {
 		// really, we should mutate this into something that isn't a TypeDecl but that requires large-scale changes,
@@ -216,5 +216,5 @@
 	}
 
-	void CodeGenerator::visit( Constant *constant ) { 
+	void CodeGenerator::visit( Constant *constant ) {
 		output << constant->get_value() ;
 	}
@@ -233,5 +233,5 @@
 						assert( arg != applicationExpr->get_args().end() );
 						if ( AddressExpr *addrExpr = dynamic_cast< AddressExpr * >( *arg ) ) {
-	        
+
 							*arg = addrExpr->get_arg();
 						} else {
@@ -242,10 +242,10 @@
 						break;
 					}
-	      
+
 				  default:
 					// do nothing
 					;
 				}
-	    
+
 				switch ( opInfo.type ) {
 				  case OT_INDEX:
@@ -256,10 +256,10 @@
 					output << "]";
 					break;
-	      
+
 				  case OT_CALL:
 					// there are no intrinsic definitions of the function call operator
 					assert( false );
 					break;
-	      
+
 				  case OT_PREFIX:
 				  case OT_PREFIXASSIGN:
@@ -270,5 +270,5 @@
 					output << ")";
 					break;
-	      
+
 				  case OT_POSTFIX:
 				  case OT_POSTFIXASSIGN:
@@ -287,5 +287,5 @@
 					output << ")";
 					break;
-	      
+
 				  case OT_CONSTANT:
 				  case OT_LABELADDRESS:
@@ -306,5 +306,5 @@
 		} // if
 	}
-  
+
 	void CodeGenerator::visit( UntypedExpr *untypedExpr ) {
 		if ( NameExpr *nameExpr = dynamic_cast< NameExpr* >( untypedExpr->get_function() ) ) {
@@ -320,9 +320,9 @@
 					output << "]";
 					break;
-	      
+
 				  case OT_CALL:
 					assert( false );
 					break;
-	      
+
 				  case OT_PREFIX:
 				  case OT_PREFIXASSIGN:
@@ -334,5 +334,5 @@
 					output << ")";
 					break;
-	      
+
 				  case OT_POSTFIX:
 				  case OT_POSTFIXASSIGN:
@@ -341,5 +341,5 @@
 					output << opInfo.symbol;
 					break;
-  
+
 				  case OT_INFIX:
 				  case OT_INFIXASSIGN:
@@ -351,5 +351,5 @@
 					output << ")";
 					break;
-					
+
 				  case OT_CONSTANT:
 					// there are no intrinsic definitions of 0 or 1 as functions
@@ -369,5 +369,5 @@
 		} // if
 	}
-  
+
 	void CodeGenerator::visit( NameExpr *nameExpr ) {
 		OperatorInfo opInfo;
@@ -379,5 +379,5 @@
 		} // if
 	}
-  
+
 	void CodeGenerator::visit( AddressExpr *addressExpr ) {
 		output << "(&";
@@ -392,31 +392,30 @@
 
 	void CodeGenerator::visit( CastExpr *castExpr ) {
-		// if the cast is to an lvalue type, then the cast
-		// should be dropped, since the result of a cast is
-		// never an lvalue in C
-		if ( castExpr->get_results().front()->get_isLvalue() ) {
-			castExpr->get_arg()->accept( *this );
-		} else {
-			output << "((";
-			if ( castExpr->get_results().empty() ) {
-				output << "void" ;
-			} else {
-				output << genType( castExpr->get_results().front(), "" );
-			} // if
+		output << "(";
+		if ( castExpr->get_results().empty() ) {
+			output << "(void)" ;
+		} else if ( ! castExpr->get_results().front()->get_isLvalue() ) {
+			// at least one result type of cast, but not an lvalue
+			output << "(";
+			output << genType( castExpr->get_results().front(), "" );
 			output << ")";
-			castExpr->get_arg()->accept( *this );
-			output << ")";			
+		} else {
+			// otherwise, the cast is to an lvalue type, so the cast
+			// should be dropped, since the result of a cast is
+			// never an lvalue in C
 		}
-	}
-  
+		castExpr->get_arg()->accept( *this );
+		output << ")";
+	}
+
 	void CodeGenerator::visit( UntypedMemberExpr *memberExpr ) {
 		assert( false );
 	}
-  
+
 	void CodeGenerator::visit( MemberExpr *memberExpr ) {
 		memberExpr->get_aggregate()->accept( *this );
 		output << "." << mangleName( memberExpr->get_member() );
 	}
-  
+
 	void CodeGenerator::visit( VariableExpr *variableExpr ) {
 		OperatorInfo opInfo;
@@ -427,10 +426,10 @@
 		} // if
 	}
-  
+
 	void CodeGenerator::visit( ConstantExpr *constantExpr ) {
 		assert( constantExpr->get_constant() );
 		constantExpr->get_constant()->accept( *this );
 	}
-  
+
 	void CodeGenerator::visit( SizeofExpr *sizeofExpr ) {
 		output << "sizeof(";
@@ -453,5 +452,5 @@
 		output << ")";
 	}
-  
+
 	void CodeGenerator::visit( LogicalExpr *logicalExpr ) {
 		output << "(";
@@ -465,5 +464,5 @@
 		output << ")";
 	}
-  
+
 	void CodeGenerator::visit( ConditionalExpr *conditionalExpr ) {
 		output << "(";
@@ -475,5 +474,5 @@
 		output << ")";
 	}
-  
+
 	void CodeGenerator::visit( CommaExpr *commaExpr ) {
 		output << "(";
@@ -483,7 +482,7 @@
 		output << ")";
 	}
-  
+
 	void CodeGenerator::visit( TupleExpr *tupleExpr ) {}
-  
+
 	void CodeGenerator::visit( TypeExpr *typeExpr ) {}
 
@@ -516,5 +515,5 @@
 			}
 		}
-		cur_indent -= CodeGenerator::tabsize; 
+		cur_indent -= CodeGenerator::tabsize;
 
 		output << indent << "}";
@@ -522,6 +521,6 @@
 
 	void CodeGenerator::visit( ExprStmt *exprStmt ) {
-		// I don't see why this check is necessary. 
-		// If this starts to cause problems then put it back in, 
+		// I don't see why this check is necessary.
+		// If this starts to cause problems then put it back in,
 		// with an explanation
 		assert( exprStmt );
@@ -573,5 +572,5 @@
 		switchStmt->get_condition()->accept( *this );
 		output << " ) ";
-		
+
 		output << "{" << std::endl;
 		cur_indent += CodeGenerator::tabsize;
@@ -593,5 +592,5 @@
 		} // if
 		output << ":\n";
-		
+
 		std::list<Statement *> sts = caseStmt->get_statements();
 
@@ -610,5 +609,5 @@
 			if ( ! branchStmt->get_target().empty() )
 				output << "goto " << branchStmt->get_target();
-			else { 
+			else {
 				if ( branchStmt->get_computedTarget() != 0 ) {
 					output << "goto *";
@@ -661,6 +660,6 @@
 
 	void CodeGenerator::visit( ForStmt *forStmt ) {
-		// initialization is always hoisted, so don't 
-		// bother doing anything with that 
+		// initialization is always hoisted, so don't
+		// bother doing anything with that
 		output << "for (;";
 
@@ -686,5 +685,5 @@
 	void CodeGenerator::visit( DeclStmt *declStmt ) {
 		declStmt->get_decl()->accept( *this );
-	
+
 		if ( doSemicolon( declStmt->get_decl() ) ) {
 			output << ";";
Index: src/GenPoly/Specialize.cc
===================================================================
--- src/GenPoly/Specialize.cc	(revision 61f9356c5a7f6b519ed835460f72dc5f34708073)
+++ src/GenPoly/Specialize.cc	(revision 803deb12902ca2c3780803d39417a86c02b8ba33)
@@ -5,11 +5,11 @@
 // file "LICENCE" distributed with Cforall.
 //
-// Specialize.cc -- 
+// Specialize.cc --
 //
 // Author           : Richard C. Bilson
 // Created On       : Mon May 18 07:44:20 2015
 // Last Modified By : Rob Schluntz
-// Last Modified On : Tue Sep 22 14:04:13 2015
-// Update Count     : 15
+// Last Modified On : Wed Jan 20 12:40:33 2016
+// Update Count     : 18
 //
 
@@ -140,6 +140,7 @@
 		return new AddressExpr( new VariableExpr( thunkFunc ) );
 	}
-	
+
 	Expression * Specialize::doSpecialization( Type *formalType, Expression *actual, InferredParams *inferParams ) {
+		assert( ! actual->get_results().empty() );
 		if ( needsSpecialization( formalType, actual->get_results().front(), env ) ) {
 			FunctionType *funType;
@@ -198,4 +199,8 @@
 	Expression * Specialize::mutate( CastExpr *castExpr ) {
 		castExpr->get_arg()->acceptMutator( *this );
+		if ( castExpr->get_results().empty() ) {
+			// can't specialize if we don't have a return value
+			return castExpr;
+		}
 		Expression *specialized = doSpecialization( castExpr->get_results().front(), castExpr->get_arg() );
 		if ( specialized != castExpr->get_arg() ) {