[PATCH] Support __builtin_ms_va_list.

[Richard Smith]

  This seems very weird to me. Can you explain a bit about the background for this? Is this to support writing variadic __attribute__((ms_abi)) functions when not targeting Win64? How is this is supposed to work when we *are* targeting Win64 directly? (Do we get a corresponding __builtin_sysv_va_list to go in the opposite direction, for instance? Are the two types the same in that case?)


================
Comment at: include/clang/Serialization/ASTBitCodes.h:1343
@@ -1340,1 +1342,3 @@
+      EXPR_LAMBDA,                // LambdaExpr
+      EXPR_MS_VA_ARG              // VAArgExpr (with isMicrosoftABI() true).
     };
----------------
Why are you using a separate StmtCode here, rather than just serializing the flag normally?


http://llvm-reviews.chandlerc.com/D1623