My clang now doesn't complain about !"foo".

src/core/SkStrokeRec.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkStrokeRec.h"
 #include "SkPaintDefaults.h"
 
@@ skipping 26 matching lines @@
             if (0 == paint.getStrokeWidth()) {
                 // hairline+fill == fill
                 fWidth = kStrokeRec_FillStyleWidth;
                 fStrokeAndFill = false;
             } else {
                 fWidth = paint.getStrokeWidth();
                 fStrokeAndFill = true;
             }
             break;
         default:
-            SkASSERT(!"unknown paint style");
+            SkDEBUGFAIL("unknown paint style");
             // fall back on just fill
             fWidth = kStrokeRec_FillStyleWidth;
             fStrokeAndFill = false;
             break;
     }
 
     // copy these from the paint, regardless of our "style"
     fMiterLimit = paint.getStrokeMiter();
     fCap        = paint.getStrokeCap();
     fJoin       = paint.getStrokeJoin();
@@ skipping 38 matching lines @@
 
     SkStroke stroker;
     stroker.setCap(fCap);
     stroker.setJoin(fJoin);
     stroker.setMiterLimit(fMiterLimit);
     stroker.setWidth(fWidth);
     stroker.setDoFill(fStrokeAndFill);
     stroker.strokePath(src, dst);
     return true;
 }