Merge pull request #1246 from amdrexu/bugfix

Fix an issue of interpolateAtVertexAMD().

glslang/MachineIndependent/ParseHelper.cpp

@@ -1585,6 +1585,9 @@ void TParseContext::builtInOpCheck(const TSourceLoc& loc, const TFunction& fnCan
     case EOpInterpolateAtCentroid:
     case EOpInterpolateAtSample:
     case EOpInterpolateAtOffset:
+#ifdef AMD_EXTENSIONS
+    case EOpInterpolateAtVertex:
+#endif
         // Make sure the first argument is an interpolant, or an array element of an interpolant
         if (arg0->getType().getQualifier().storage != EvqVaryingIn) {
             // It might still be an array element.