fix return values of __builtin_classify_type

Author: Daniel Kroening

regression/ansi-c/gcc_builtins4/main.c

@@ -7,18 +7,26 @@ union { int i; } u;
 enum { Econst } e;
 int a[10];
 
-STATIC_ASSERT(__builtin_classify_type(*(void *)0)==0);
 STATIC_ASSERT(__builtin_classify_type((int)0)==1);
-STATIC_ASSERT(__builtin_classify_type(e)==3);
+STATIC_ASSERT(__builtin_classify_type(e)==1);
+#ifndef __clang__
+STATIC_ASSERT(__builtin_classify_type((_Bool)0)==1);
+#else
 STATIC_ASSERT(__builtin_classify_type((_Bool)0)==4);
+#endif
 STATIC_ASSERT(__builtin_classify_type((int *)0)==5);
 STATIC_ASSERT(__builtin_classify_type(1.0)==8);
 STATIC_ASSERT(__builtin_classify_type(*(0?(void *)0:(double *)0))==8);
 STATIC_ASSERT(__builtin_classify_type(*(0?(double *)0:(void *)0))==8);
 STATIC_ASSERT(__builtin_classify_type((_Complex double)0)==9);
 STATIC_ASSERT(__builtin_classify_type(s)==12);
 STATIC_ASSERT(__builtin_classify_type(u)==13);
-STATIC_ASSERT(__builtin_classify_type(a)==14);
+STATIC_ASSERT(__builtin_classify_type(a)==5);
+#ifndef __clang__
+STATIC_ASSERT(__builtin_classify_type((char)0)==15);
+#else
+STATIC_ASSERT(__builtin_classify_type((char)0)==1);
+#endif
 
 #endif
 

regression/ansi-c/gcc_builtins4/test.desc

@@ -1,4 +1,4 @@
-CORE
+KNOWNBUG
 main.c
 
 ^EXIT=0$

src/ansi-c/c_typecheck_expr.cpp

@@ -2581,7 +2581,7 @@ exprt c_typecheck_baset::do_special_functions(
   }
   else if(identifier=="__builtin_classify_type")
   {
-    // This is a gcc extension that produces an integer
+    // This is a gcc/clang extension that produces an integer
     // constant for the type of the argument expression.
     if(expr.arguments().size()!=1)
     {
@@ -2598,18 +2598,18 @@ exprt c_typecheck_baset::do_special_functions(
 
     unsigned type_number=
       type.id()==ID_empty?0:
-      type.id()==ID_c_enum_tag?3:
+      type.id()==ID_c_enum_tag?1:
       (type.id()==ID_bool || type.id()==ID_c_bool)?4:
       type.id()==ID_pointer?5:
       type.id()==ID_floatbv?8:
       (type.id()==ID_complex && type.subtype().id()==ID_floatbv)?9:
       type.id()==ID_struct?12:
       type.id()==ID_union?13:
-      type.id()==ID_array?14:
+      type.id()==ID_array?5:
       1; // int, short
 
-    // clang returns 15 for the three 'char' types,
-    // gcc treats these as 'int'
+    // clang returns 15 for the three 'char' types, gcc treats these as 'int'.
+    // clang returns 4 for _Bool, gcc treats these as 'int'.
 
     exprt tmp=from_integer(type_number, expr.type());
     tmp.add_source_location()=source_location;