[Modules] Add stdatomic to the list of builtin headers

Since it's provided by the compiler. This allows a system module map
file to declare a module for it.

No test change for cstd.m, since stdatomic.h doesn't function without a
relatively complete stdint.h and stddef.h, which tests using this module
don't provide.

rdar://problem/24931246

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@263076 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Lex/ModuleMap.cpp b/lib/Lex/ModuleMap.cpp
index a50cca3c4b2064f5e65eca30eb54024cc3300480..5e103a054d5c77cbf22ea54bdc8d3c8048a317a5 100644 (file)
--- a/lib/Lex/ModuleMap.cpp
+++ b/lib/Lex/ModuleMap.cpp
@@ -151,6 +151,7 @@ static bool isBuiltinHeader(StringRef FileName) {
            .Case("limits.h", true)
            .Case("stdalign.h", true)
            .Case("stdarg.h", true)
+           .Case("stdatomic.h", true)
            .Case("stdbool.h", true)
            .Case("stddef.h", true)
            .Case("stdint.h", true)