Sema: provide an extension warning for enable_if

Clang implements an enable_if attribute as an extension.  Hook up `-Wpedantic`
to issue an extension usage warning when __enable_if__ is used.

llvm-svn: 261192

1 files changed, 50 insertions, 0 deletions

diff --git a/clang/test/Sema/enable_if-ext.c b/clang/test/Sema/enable_if-ext.c
new file mode 100644
index 00000000000..1e605d49b60
--- /dev/null
+++ b/clang/test/Sema/enable_if-ext.c
@@ -0,0 +1,50 @@
+// RUN: %clang_cc1 -fsyntax-only %s -include %s -verify
+// RUN: %clang_cc1 -Wpedantic -fsyntax-only %s -include %s -verify -DWARN_PEDANTIC
+
+#ifndef enable_if_ext_included
+#define enable_if_ext_included
+
+#if !defined(WARN_PEDANTIC)
+// expected-no-diagnostics
+#endif
+
+__attribute__ (( enable_if(1, "") ))
+#if defined(WARN_PEDANTIC)
+// expected-warning@-2 {{'enable_if' is a clang extension}}
+#endif
+void f() { }
+
+__attribute__ (( __enable_if__(1, "") ))
+#if defined(WARN_PEDANTIC)
+// expected-warning@-2 {{'enable_if' is a clang extension}}
+#endif
+void g() { }
+
+__attribute__ (( enable_if(0, "") ))
+#if defined(WARN_PEDANTIC)
+// expected-warning@-2 {{'enable_if' is a clang extension}}
+#endif
+void h() { }
+
+__attribute__ (( __enable_if__(0, "") ))
+#if defined(WARN_PEDANTIC)
+// expected-warning@-2 {{'enable_if' is a clang extension}}
+#endif
+void i() { }
+
+#pragma clang system_header
+
+__attribute__ (( enable_if(1, "") ))
+void j() { }
+
+__attribute__ (( __enable_if__(1, "") ))
+void k() { }
+
+__attribute__ (( enable_if(0, "") ))
+void l() { }
+
+__attribute__ (( __enable_if__(0, "") ))
+void m() { }
+
+#endif
+