Fix handling of invalid uses of the __has_warning builtin macro

llvm-svn: 168265

clang/lib/Lex/PPMacroExpansion.cpp

@@ -1291,7 +1291,10 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
           StartLoc = Tok.getLocation();
           IsValid = false;
           // Eat tokens until ')'.
-          do Lex(Tok); while (!(Tok.is(tok::r_paren) || Tok.is(tok::eod)));
+          while (Tok.isNot(tok::r_paren)
+                   && Tok.isNot(tok::eod)
+                   && Tok.isNot(tok::eof))
+            Lex(Tok);
           break;
         }
         
@@ -1342,7 +1345,8 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
       Diag(StartLoc, diag::err_warning_check_malformed);
 
     OS << (int)Value;
-    Tok.setKind(tok::numeric_constant);
+    if (IsValid)
+      Tok.setKind(tok::numeric_constant);
   } else if (II == Ident__building_module) {
     // The argument to this builtin should be an identifier. The
     // builtin evaluates to 1 when that identifier names the module we are

clang/test/Preprocessor/invalid-__has_warning1.c

@@ -0,0 +1,5 @@
+// RUN: %clang_cc1 -verify %s
+
+// These must be the last lines in this test.
+// expected-error@+1{{requires a parenthesized string}} expected-error@+1 2{{expected}}
+int i = __has_warning(

clang/test/Preprocessor/invalid-__has_warning2.c

@@ -0,0 +1,5 @@
+// RUN: %clang_cc1 -verify %s
+
+// These must be the last lines in this test.
+// expected-error@+1{{requires a parenthesized string}} expected-error@+1{{expected}}
+int i = __has_warning();

clang/test/Preprocessor/warning_tests.c

@@ -11,7 +11,9 @@
 #warning Should have -Wparentheses
 #endif
 
-#if __has_warning(-Wfoo) // expected-error {{builtin warning check macro requires a parenthesized string}}
+// expected-error@+2 {{builtin warning check macro requires a parenthesized string}}
+// expected-error@+1 {{expected value in expression}}
+#if __has_warning(-Wfoo)
 #endif
 
 // expected-warning@+3 {{Not a valid warning flag}}