Merge pull request #5676 from tautschnig/void

C/C++ front-end: do not accept void-typed objects or members

Author: tautschnig

regression/ansi-c/invalid_use_of_void1/main.c

@@ -0,0 +1,21 @@
+struct a
+{
+#ifdef void_member
+  void b;
+#else
+  int b;
+#endif
+};
+struct a *ae;
+void d()
+{
+  ae->b;
+}
+#ifdef void_global
+void x;
+#endif
+int main()
+{
+  void v;
+  d();
+}

regression/ansi-c/invalid_use_of_void1/test-global.desc

@@ -0,0 +1,9 @@
+CORE test-c++-front-end
+main.c
+-Dvoid_global
+^EXIT=(64|1)$
+^SIGNAL=0$
+void-typed symbol not permitted
+^CONVERSION ERROR$
+--
+Invariant check failed

regression/ansi-c/invalid_use_of_void1/test-non-member.desc

@@ -0,0 +1,9 @@
+CORE test-c++-front-end
+main.c
+
+^EXIT=(64|1)$
+^SIGNAL=0$
+void-typed symbol not permitted
+^CONVERSION ERROR$
+--
+Invariant check failed

regression/ansi-c/invalid_use_of_void1/test.desc

@@ -0,0 +1,9 @@
+CORE test-c++-front-end
+main.c
+-Dvoid_member
+^EXIT=(64|1)$
+^SIGNAL=0$
+void-typed member not permitted
+^CONVERSION ERROR$
+--
+Invariant check failed

src/ansi-c/c_typecheck_base.cpp

@@ -103,6 +103,13 @@ void c_typecheck_baset::typecheck_symbol(symbolt &symbol)
     symbol.pretty_name=new_name;
   }
 
+  if(!symbol.is_type && symbol.type.id() == ID_empty)
+  {
+    error().source_location = symbol.location;
+    error() << "void-typed symbol not permitted" << eom;
+    throw 0;
+  }
+
   // see if we have it already
   symbol_tablet::symbolst::const_iterator old_it=
     symbol_table.symbols.find(symbol.name);

src/ansi-c/c_typecheck_type.cpp

@@ -934,6 +934,13 @@ void c_typecheck_baset::typecheck_compound_body(
           throw 0;
         }
 
+        if(new_component.type().id() == ID_empty)
+        {
+          error().source_location = source_location;
+          error() << "void-typed member not permitted" << eom;
+          throw 0;
+        }
+
         components.push_back(new_component);
       }
     }

src/cpp/cpp_typecheck_code.cpp

@@ -448,6 +448,13 @@ void cpp_typecheckt::typecheck_decl(codet &code)
     if(is_typedef)
       continue;
 
+    if(!symbol.is_type && symbol.type.id() == ID_empty)
+    {
+      error().source_location = symbol.location;
+      error() << "void-typed symbol not permitted" << eom;
+      throw 0;
+    }
+
     code_declt decl_statement(cpp_symbol_expr(symbol));
     decl_statement.add_source_location()=symbol.location;
 

src/cpp/cpp_typecheck_compound_type.cpp

@@ -317,6 +317,13 @@ void cpp_typecheckt::typecheck_compound_declarator(
 
   typecheck_type(final_type);
 
+  if(final_type.id() == ID_empty)
+  {
+    error().source_location = declaration.type().source_location();
+    error() << "void-typed member not permitted" << eom;
+    throw 0;
+  }
+
   cpp_namet cpp_name;
   cpp_name.swap(declarator.name());
 

src/cpp/cpp_typecheck_declaration.cpp

@@ -148,6 +148,13 @@ void cpp_typecheckt::convert_non_template_declaration(
       declaration_type, declaration.storage_spec(),
       declaration.member_spec(), declarator);
 
+    if(!symbol.is_type && symbol.type.id() == ID_empty)
+    {
+      error().source_location = symbol.location;
+      error() << "void-typed symbol not permitted" << eom;
+      throw 0;
+    }
+
     // any template instance to remember?
     if(declaration.find(ID_C_template).is_not_nil())
     {