[PATCH] D1623: Support __builtin_ms_va_list.

[Richard Smith via cfe-commits]

rsmith added inline comments.

================
Comment at: lib/Sema/SemaExpr.cpp:11664-11672
@@ -11662,1 +11663,11 @@
+
+  // It might be a __builtin_ms_va_list.
+  if (!E->isTypeDependent() && Context.getTargetInfo().hasBuiltinMSVaList()) {
+    QualType MSVaListType = Context.getBuiltinMSVaListType();
+    if (Context.hasSameType(MSVaListType, E->getType())) {
+      if (CheckForModifiableLvalue(E, BuiltinLoc, *this))
+        return ExprError();
+      IsMS = true;
+    }
+  }
 
----------------
If `__builtin_va_list` and `__builtin_ms_va_list` are the same type, this will set `IsMS` to true, which is not wrong per se but seems a bit surprising. (`IsMS` is the "I'm using an unnatural ABI" flag, and I think it'd be a bit better to not set it for normal `va_start` / `va_arg` / `va_end`, even when targeting the MS ABI. Thoughts?


http://reviews.llvm.org/D1623