From 5ef26fb4fd9d6a3ac7b35eb5f3a2a4814449a28f Mon Sep 17 00:00:00 2001
From: Ted Kremenek <kremenek@apple.com>
Date: Thu, 3 Dec 2009 01:34:15 +0000
Subject: [PATCH] Add 'has_feature(cxx_exceptions)' to allow code to determine
 via preprocessor logic if C++ exceptions are enabled.

llvm-svn: 90378
---
 clang/lib/Lex/PPMacroExpansion.cpp          |  3 +++
 clang/test/Lexer/has_feature_exceptions.cpp | 11 +++++++++++
 2 files changed, 14 insertions(+)
 create mode 100644 clang/test/Lexer/has_feature_exceptions.cpp

diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp
index 6181e17e602d..25f8b113c34d 100644
--- a/clang/lib/Lex/PPMacroExpansion.cpp
+++ b/clang/lib/Lex/PPMacroExpansion.cpp
@@ -488,6 +488,9 @@ static bool HasFeature(const Preprocessor &PP, const IdentifierInfo *II) {
     return false;
   case 8:
     if (II->isStr("cxx_rtti")) return LangOpts.RTTI;
+    return false;
+  case 14:
+    if (II->isStr("cxx_exceptions")) return LangOpts.Exceptions;
     return false;      
   case 19:
     if (II->isStr("objc_nonfragile_abi")) return LangOpts.ObjCNonFragileABI;
diff --git a/clang/test/Lexer/has_feature_exceptions.cpp b/clang/test/Lexer/has_feature_exceptions.cpp
new file mode 100644
index 000000000000..231a6c56a45b
--- /dev/null
+++ b/clang/test/Lexer/has_feature_exceptions.cpp
@@ -0,0 +1,11 @@
+// RUN: clang -E -fexceptions %s -o - | FileCheck --check-prefix=CHECK-EXCEPTIONS %s
+// RUN: clang -E -fno-exceptions %s -o - | FileCheck --check-prefix=CHECK-NO-EXCEPTIONS %s
+
+#if __has_feature(cxx_exceptions)
+int foo();
+#else
+int bar();
+#endif
+
+// CHECK-EXCEPTIONS: foo
+// CHECK-NO-EXCEPTIONS: bar