Sema: handle `wint_t` more carefully for printf checking

In the case that `win_t` is an `unsigned short` (e.g. on Windows), we would
previously incorrectly diagnose the conversion because we would immediately
promote the argument type from `wint_t` (aka `unsigned short`) to `int` before
checking if the type matched.  This should repair the Windows hosted bots.

llvm-svn: 342565

1 files changed, 6 insertions, 4 deletions

diff --git a/clang/lib/Analysis/FormatString.cpp b/clang/lib/Analysis/FormatString.cpp
index f37e4affae3..0bab50c569f 100644
--- a/clang/lib/Analysis/FormatString.cpp
+++ b/clang/lib/Analysis/FormatString.cpp
@@ -406,12 +406,14 @@ ArgType::matchesType(ASTContext &C, QualType argTy) const {
     }
 
     case WIntTy: {
+      QualType WInt = C.getCanonicalType(C.getWIntType()).getUnqualifiedType();
 
-      QualType PromoArg =
-        argTy->isPromotableIntegerType()
-          ? C.getPromotedIntegerType(argTy) : argTy;
+      if (C.getCanonicalType(argTy).getUnqualifiedType() == WInt)
+        return Match;
 
-      QualType WInt = C.getCanonicalType(C.getWIntType()).getUnqualifiedType();
+      QualType PromoArg = argTy->isPromotableIntegerType()
+                              ? C.getPromotedIntegerType(argTy)
+                              : argTy;
       PromoArg = C.getCanonicalType(PromoArg).getUnqualifiedType();
 
       // If the promoted argument is the corresponding signed type of the