Merging r341697:

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r341697 | arphaman | 2018-09-07 11:59:45 -0700 (Fri, 07 Sep 2018) | 4 lines

warn_stdlibcxx_not_found: suggest '-stdlib=libc++' instead of '-std'

Addresses first post-commit feedback for r335081 from Nico

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llvm-svn: 347276

Author: tstellar

clang/include/clang/Basic/DiagnosticFrontendKinds.td

@@ -238,7 +238,7 @@ def warn_option_invalid_ocl_version : Warning<
   "OpenCL version %0 does not support the option '%1'">, InGroup<Deprecated>;
 
 def warn_stdlibcxx_not_found : Warning<
-  "include path for stdlibc++ headers not found; pass '-std=libc++' on the "
+  "include path for stdlibc++ headers not found; pass '-stdlib=libc++' on the "
   "command line to use the libc++ standard library instead">,
   InGroup<DiagGroup<"stdlibcxx-not-found">>;
 }

clang/test/Frontend/warning-stdlibcxx-darwin.cpp

@@ -1,5 +1,5 @@
 // RUN: %clang -cc1 -triple arm64-apple-ios6.0.0 -isysroot %S/doesnotexist %s 2>&1 | FileCheck %s
 // RUN: %clang -cc1 -triple arm64-apple-ios6.0.0 -isysroot %S/doesnotexist -stdlib=libc++ %s -verify
-// CHECK: include path for stdlibc++ headers not found; pass '-std=libc++' on the command line to use the libc++ standard library instead
+// CHECK: include path for stdlibc++ headers not found; pass '-stdlib=libc++' on the command line to use the libc++ standard library instead
 
 // expected-no-diagnostics