Preprocessor:removeParentheses: fixed potential buffer access out of bounds, if find returns std::string::npos.

lib/preprocessor.cpp

@@ -819,9 +819,12 @@ std::string Preprocessor::removeParentheses(const std::string &str)
                         --ind;
                         if (ind == 0) {
                             if (i == line.length() - 1) {
-                                line[line.find('(')] = ' ';
+                                const std::string::size_type posIndx = line.find('(');
+                                if (posIndx != std::string::npos) {
+                                    line[posIndx] = ' ';
                                     line.erase(line.length() - 1);
                                 }
+                            }
                             break;
                         }
                     }