Special case '%C' handling in ObjC format strings to handle integer literals that can represent unicode characters

Fixes <rdar://problem/13991617>.

llvm-svn: 192673

1 files changed, 9 insertions, 1 deletions

diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 94a58cc625a..b0950ab7e65 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -3115,7 +3115,15 @@ CheckPrintfHandler::checkFormatExpr(const analyze_printf::PrintfSpecifier &FS,
       // 'unichar' is defined as a typedef of unsigned short, but we should
       // prefer using the typedef if it is visible.
       IntendedTy = S.Context.UnsignedShortTy;
-      
+
+      // While we are here, check if the value is an IntegerLiteral that happens
+      // to be within the valid range.
+      if (const IntegerLiteral *IL = dyn_cast<IntegerLiteral>(E)) {
+        const llvm::APInt &V = IL->getValue();
+        if (V.getActiveBits() <= S.Context.getTypeSize(IntendedTy))
+          return true;
+      }
+
       LookupResult Result(S, &S.Context.Idents.get("unichar"), E->getLocStart(),
                           Sema::LookupOrdinaryName);
       if (S.LookupName(Result, S.getCurScope())) {