Fix inversion in argument type checking for format strings with conversion specifiers for character types.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@135046 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Analysis/FormatString.cpp

@@ -225,10 +225,10 @@ bool ArgTypeResult::matchesType(ASTContext &C, QualType argTy) const {
             break;
           case BuiltinType::Char_S:
           case BuiltinType::SChar:
-            return T == C.UnsignedCharTy;
+            return T == C.SignedCharTy;
           case BuiltinType::Char_U:
           case BuiltinType::UChar:
-            return T == C.SignedCharTy;
+            return T == C.UnsignedCharTy;
           case BuiltinType::Short:
             return T == C.UnsignedShortTy;
           case BuiltinType::UShort:

test/Sema/format-strings.c

@@ -363,3 +363,12 @@ int printf(const char * restrict, ...) __attribute__((__format__ (__printf__, 1,
 void rdar9612060(void) {
   printf("%s", 2); // expected-warning{{conversion specifies type 'char *' but the argument has type 'int'}}
 }
+
+void check_char(unsigned char x, signed char y) {
+  printf("%c", y); // no-warning
+  printf("%hhu", x); // no-warning
+  printf("%hhi", y); // no-warning
+  printf("%hhi", x); // expected-warning{{conversion specifies type 'signed char' but the argument has type 'unsigned char'}}
+  printf("%c", x); // no-warning
+  printf("%hhu", y); // expected-warning{{conversion specifies type 'unsigned char' but the argument has type 'signed char'}}
+}