[clang] [clang] Add /Zc:__STDC__ flag to clang-cl (PR #68690)

[via cfe-commits]

================
@@ -291,6 +291,7 @@ LANGOPT(HIPStdParInterposeAlloc, 1, 0, "Replace allocations / deallocations with
 
 LANGOPT(OpenACC           , 1, 0, "OpenACC Enabled")
 
+LANGOPT(MSVCEnableStdcMacro , 1, 0, "Define __STDC__ with '-fms-compatability'")
----------------
xbjfk wrote:

Good catch!

https://github.com/llvm/llvm-project/pull/68690