From 53b4b1846d21ab045af21ff8227c8eddf2b1a8ba Mon Sep 17 00:00:00 2001
From: Alex Lorenz <arphaman@gmail.com>
Date: Wed, 12 Apr 2017 11:03:25 +0000
Subject: [PATCH] Add support for __builtin_available to __has_builtin

rdar://31576715

llvm-svn: 300049
---
 clang/lib/Lex/PPMacroExpansion.cpp | 1 +
 clang/test/Parser/objc-available.m | 5 +++++
 2 files changed, 6 insertions(+)

diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp
index de166c75e2cb..358c96a78300 100644
--- a/clang/lib/Lex/PPMacroExpansion.cpp
+++ b/clang/lib/Lex/PPMacroExpansion.cpp
@@ -1746,6 +1746,7 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
           return llvm::StringSwitch<bool>(II->getName())
                       .Case("__make_integer_seq", LangOpts.CPlusPlus)
                       .Case("__type_pack_element", LangOpts.CPlusPlus)
+                      .Case("__builtin_available", true)
                       .Default(false);
         }
       });
diff --git a/clang/test/Parser/objc-available.m b/clang/test/Parser/objc-available.m
index d18ac1f13445..a170721240ce 100644
--- a/clang/test/Parser/objc-available.m
+++ b/clang/test/Parser/objc-available.m
@@ -20,3 +20,8 @@ void f() {
   (void)@available(macos); // expected-error{{expected a version}}
   (void)@available; // expected-error{{expected '('}}
 }
+
+#if __has_builtin(__builtin_available)
+#error expected
+// expected-error@-1 {{expected}}
+#endif