Fix case where GrGLEffectMatrix gives back a dangling ptr for the coords var name.

src/effects/gradients/SkTwoPointRadialGradient.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 "SkTwoPointRadialGradient.h"
 
@@ skipping 515 matching lines @@
 }
 
 void GrGLRadial2Gradient::emitCode(GrGLShaderBuilder* builder,
                                    const GrDrawEffect& drawEffect,
                                    EffectKey key,
                                    const char* outputColor,
                                    const char* inputColor,
                                    const TextureSamplerArray& samplers) {
 
     this->emitYCoordUniform(builder);
-    const char* fsCoords;
-    const char* vsCoordsVarying;
+    SkString fsCoords;
+    SkString vsCoordsVarying;
     GrSLType coordsVaryingType;
     this->setupMatrix(builder, key, &fsCoords, &vsCoordsVarying, &coordsVaryingType);
 
     // 2 copies of uniform array, 1 for each of vertex & fragment shader,
     // to work around Xoom bug. Doesn't seem to cause performance decrease
     // in test apps, but need to keep an eye on it.
     fVSParamUni = builder->addUniformArray(GrGLShaderBuilder::kVertex_ShaderType,
                                            kFloat_GrSLType, "Radial2VSParams", 6);
     fFSParamUni = builder->addUniformArray(GrGLShaderBuilder::kFragment_ShaderType,
                                            kFloat_GrSLType, "Radial2FSParams", 6);
@@ skipping 10 matching lines @@
         SkString p3;
         builder->getUniformVariable(fVSParamUni).appendArrayAccess(2, &p2);
         builder->getUniformVariable(fVSParamUni).appendArrayAccess(3, &p3);
 
         // For radial gradients without perspective we can pass the linear
         // part of the quadratic as a varying.
         if (kVec2f_GrSLType == coordsVaryingType) {
             // r2Var = 2 * (r2Parm[2] * varCoord.x - r2Param[3])
             builder->vsCodeAppendf("\t%s = 2.0 *(%s * %s.x - %s);\n",
                                    fVSVaryingName, p2.c_str(),
-                                   vsCoordsVarying, p3.c_str());
+                                   vsCoordsVarying.c_str(), p3.c_str());
         }
     }
 
     // FS
     {
         SkString cName("c");
         SkString ac4Name("ac4");
         SkString rootName("root");
         SkString t;
         SkString p0;
@@ skipping 10 matching lines @@
         builder->getUniformVariable(fFSParamUni).appendArrayAccess(5, &p5);
 
         // If we we're able to interpolate the linear component,
         // bVar is the varying; otherwise compute it
         SkString bVar;
         if (kVec2f_GrSLType == coordsVaryingType) {
             bVar = fFSVaryingName;
         } else {
             bVar = "b";
             builder->fsCodeAppendf("\tfloat %s = 2.0 * (%s * %s.x - %s);\n",
-                                   bVar.c_str(), p2.c_str(), fsCoords, p3.c_str());
+                                   bVar.c_str(), p2.c_str(), fsCoords.c_str(), p3.c_str());
         }
 
         // c = (x^2)+(y^2) - params[4]
         builder->fsCodeAppendf("\tfloat %s = dot(%s, %s) - %s;\n",
                                cName.c_str(),
-                               fsCoords,
-                               fsCoords,
+                               fsCoords.c_str(),
+                               fsCoords.c_str(),
                                p4.c_str());
 
         // If we aren't degenerate, emit some extra code, and accept a slightly
         // more complex coord.
         if (!fIsDegenerate) {
 
             // ac4 = 4.0 * params[0] * c
             builder->fsCodeAppendf("\tfloat %s = %s * 4.0 * %s;\n",
                                    ac4Name.c_str(), p0.c_str(),
                                    cName.c_str());
@@ skipping 88 matching lines @@
 }
 
 #else
 
 GrEffectRef* SkTwoPointRadialGradient::asNewEffect(GrContext*, const SkPaint&) const {
     SkDEBUGFAIL("Should not call in GPU-less build");
     return NULL;
 }
 
 #endif