From: Alp Toker <alp@nuanti.com>
Date: Wed, 25 Dec 2013 01:47:02 +0000 (+0000)
Subject: Don't reserve __builtin_types_compatible_p as a C++ keyword
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=a693f7de5d45c718ae9b82310d456c51bcda2422;p=clang

Don't reserve __builtin_types_compatible_p as a C++ keyword

Even g++ considers this a valid C++ identifier and it should only have been
visible in C mode.

Also drop the associated low-value diagnostic.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@197995 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 3a3c93da12..71d118a2be 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -367,8 +367,6 @@ def warn_redecl_library_builtin : Warning<
   "incompatible redeclaration of library function %0">,
   InGroup<DiagGroup<"incompatible-library-redeclaration">>;
 def err_builtin_definition : Error<"definition of builtin function %0">;
-def err_types_compatible_p_in_cplusplus : Error<
-  "__builtin_types_compatible_p is not valid in C++">;
 def warn_builtin_unknown : Warning<"use of unknown builtin %0">,
   InGroup<ImplicitFunctionDeclare>, DefaultError;
 def warn_dyn_class_memaccess : Warning<
diff --git a/include/clang/Basic/TokenKinds.def b/include/clang/Basic/TokenKinds.def
index a76d86bb2c..54f7853648 100644
--- a/include/clang/Basic/TokenKinds.def
+++ b/include/clang/Basic/TokenKinds.def
@@ -348,7 +348,7 @@ KEYWORD(__builtin_choose_expr       , KEYALL)
 KEYWORD(__builtin_offsetof          , KEYALL)
 // __builtin_types_compatible_p is a GNU C extension that we handle like a C++
 // type trait.
-TYPE_TRAIT_2(__builtin_types_compatible_p, TypeCompatible, KEYALL)
+TYPE_TRAIT_2(__builtin_types_compatible_p, TypeCompatible, KEYNOCXX)
 KEYWORD(__builtin_va_arg            , KEYALL)
 KEYWORD(__extension__               , KEYALL)
 KEYWORD(__imag                      , KEYALL)
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index a0c123fdaa..2591dbfede 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -3707,16 +3707,7 @@ static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc,
 ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc, 
                                 ArrayRef<TypeSourceInfo *> Args, 
                                 SourceLocation RParenLoc) {
-  QualType ResultType = Context.BoolTy;
-  // __builtin_types_compatible_p is a GNU C extension, not a C++ type trait.
-  if (Kind == BTT_TypeCompatible) {
-    ResultType = Context.IntTy;
-    if (getLangOpts().CPlusPlus) {
-      Diag(KWLoc, diag::err_types_compatible_p_in_cplusplus)
-          << SourceRange(KWLoc, RParenLoc);
-      return ExprError();
-    }
-  }
+  QualType ResultType = Context.getLogicalOperationType();
 
   bool Dependent = false;
   for (unsigned I = 0, N = Args.size(); I != N; ++I) {
diff --git a/test/SemaCXX/types_compatible_p.cpp b/test/SemaCXX/types_compatible_p.cpp
index 4aa9a1cfa9..ebff53f7c0 100644
--- a/test/SemaCXX/types_compatible_p.cpp
+++ b/test/SemaCXX/types_compatible_p.cpp
@@ -1,5 +1,8 @@
-// RUN: %clang_cc1 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -fsyntax-only -verify -x c++ %s
+// RUN: %clang_cc1 -fsyntax-only -x c %s
 
-bool f() {
-  return __builtin_types_compatible_p(int, const int); // expected-error{{C++}}
+// Test that GNU C extension __builtin_types_compatible_p() is not available in C++ mode.
+
+int f() {
+  return __builtin_types_compatible_p(int, const int); // expected-error{{}}
 }