fix for qualifiers

git-svn-id: svn+ssh://svn.cprover.org/srv/svn/cbmc/trunk@1334 6afb6bc1-c8e4-404c-8f48-9ae832c5b171

src/ansi-c/ansi_c_convert_type.cpp

@@ -170,7 +170,9 @@ void ansi_c_convert_typet::read_rec(const typet &type)
       alignment=static_cast<const exprt &>(type.find(ID_size));
   }
   else if(type.id()==ID_transparent_union)
-    transparent_union=true;
+  {
+    c_qualifiers.is_transparent_union=true;
+  }
   else if(type.id()==ID_vector)
     vector_size=to_vector_type(type).size();
   else if(type.id()==ID_void)
@@ -435,9 +437,6 @@ void ansi_c_convert_typet::write(typet &type)
 
   c_qualifiers.write(type);
 
-  if(transparent_union)
-    type.set(ID_C_transparent_union, true);
-
   if(packed)
     type.set(ID_C_packed, true);
 

src/ansi-c/ansi_c_convert_type.h

@@ -29,7 +29,7 @@ public:
            gcc_float128_cnt, bv_cnt, bv_width;
   bool gcc_mode_QI, gcc_mode_HI, gcc_mode_SI, gcc_mode_DI;
            
-  bool transparent_union, packed, aligned;
+  bool packed, aligned;
   exprt vector_size, alignment;
 
   // storage spec
@@ -62,7 +62,7 @@ public:
     bv_width=0;
     gcc_mode_QI=gcc_mode_HI=gcc_mode_SI=gcc_mode_DI=false;
     
-    packed=aligned=transparent_union=false;
+    packed=aligned=false;
 
     other.clear();
     c_storage_spec.clear();

src/ansi-c/c_typecast.cpp

@@ -262,16 +262,15 @@ typet c_typecastt::follow_with_qualifiers(const typet &src_type)
   typet result_type=src_type;
   
   // collect qualifiers
-  c_qualifierst qualifiers;
+  c_qualifierst qualifiers(src_type);
   
   while(result_type.id()==ID_symbol)
   {
-    qualifiers+=c_qualifierst(result_type);
-
     const symbolt &followed_type_symbol=
       ns.lookup(result_type.get(ID_identifier));
 
     result_type=followed_type_symbol.type;
+    qualifiers+=c_qualifierst(followed_type_symbol.type);
   }
 
   qualifiers.write(result_type);
@@ -493,15 +492,17 @@ void c_typecastt::implicit_typecast_followed(
   const typet &src_type,
   const typet &dest_type)
 {
+  if(dest_type.id()==ID_union)
+
   // do transparent union
   if(dest_type.id()==ID_union &&
      dest_type.get_bool(ID_C_transparent_union) &&
      src_type.id()!=ID_union)
   {
-    // the argument corresponding to a transparent union type can be of any
-    // type in the union; no cast is required
+    // The argument corresponding to a transparent union type can be of any
+    // type in the union; no explicit cast is required.
     
-    // check union members
+    // Check union members.
     const union_typet &dest_union_type=to_union_type(dest_type);
 
     for(union_typet::componentst::const_iterator

src/ansi-c/c_typecheck_type.cpp

@@ -566,7 +566,7 @@ void c_typecheck_baset::typecheck_symbol_type(typet &type)
   
   if(symbol.is_macro)
   {
-    // overwrite, but preserve any qualifiers
+    // overwrite, but preserve (add) any qualifiers
     c_qualifierst c_qualifiers(type);
     c_qualifiers+=c_qualifierst(symbol.type);
     type=symbol.type;