Issue #39: Prevent problem of inserting a zero-length symbol after cascading errors.

glslang/MachineIndependent/ParseHelper.cpp

@@ -1626,12 +1626,13 @@ void TParseContext::variableCheck(TIntermTyped*& nodePtr)
         error(symbol->getLoc(), "undeclared identifier", symbol->getName().c_str(), "");
 
         // Add to symbol table to prevent future error messages on the same name
-
+        if (symbol->getName().size() > 0) {
             TVariable* fakeVariable = new TVariable(&symbol->getName(), TType(EbtFloat));
             symbolTable.insert(*fakeVariable);
 
             // substitute a symbol node for this new variable
             nodePtr = intermediate.addSymbol(*fakeVariable, symbol->getLoc());
+        }
     } else {
         switch (symbol->getQualifier().storage) {
         case EvqPointCoord: