Looks good to me, as a drive by. ================ Comment at: test/CodeGen/mips-vaarg.c:6 @@ +5,3 @@ + +int foo (int a, ...) +{ ---------------- Seems light. How about doing CHECK-LABEL on 'define i32 @foo' and looking for call @llvm.va_start and end? http://reviews.llvm.org/D4742