Fixe bogus error for variable argument methods. Sema::ObjcGetTypeForMethodDefinition() wasn't preserving the isVariadic boolean. Another fix is to avoid synthsizing the function decl entirely, however this is a separate issue that I don't want to deal with now. Also added a FIXME to Sema::CheckFunctionCall(), which is currently emitting a bogus warning.

llvm-svn: 45146

clang/Sema/SemaChecking.cpp

@@ -62,7 +62,7 @@ Sema::CheckFunctionCall(Expr *Fn,
            diag::err_va_start_used_in_non_variadic_function);
       return true;
     }
-      
+    // FIXME: This isn't correct for methods (results in bogus warning).
     bool SecondArgIsLastNamedArgument = false;
     if (DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Args[1])) {
       if (ParmVarDecl *PV = dyn_cast<ParmVarDecl>(DR->getDecl())) {

clang/Sema/SemaType.cpp

@@ -366,7 +366,7 @@ QualType Sema::ObjcGetTypeForMethodDefinition(DeclTy *D) {
     ArgTys.push_back(ArgTy);
   }
   T = Context.getFunctionType(T, &ArgTys[0], ArgTys.size(),
-                              false);
+                              MDecl->isVariadic());
   return T;
 }
 

clang/test/Sema/va-method.m

@@ -0,0 +1,17 @@
+// RUN: clang -fsyntax-only -verify %s
+
+#include <stdarg.h>
+
+@interface NSObject @end
+@interface XX : NSObject @end
+
+@implementation XX
+- (void)encodeValuesOfObjCTypes:(const char *)types, ... {
+   va_list ap;
+   va_start(ap, types); // expected-warning {{second parameter of 'va_start' not last named argument}}
+   while (*types) ;
+   va_end(ap);
+}
+
+@end
+