improve error message

Author: ludviggunne

simplecpp.cpp

@@ -2837,7 +2837,7 @@ static bool simplifyName(simplecpp::TokenList &expr, simplecpp::OutputList *outp
                     simplecpp::Output err(tok->location.files);
                     err.type = simplecpp::Output::SYNTAX_ERROR;
                     err.location = tok->location;
-                    err.msg = "Undefined function-like macro in directive";
+                    err.msg = "Undefined function-like macro in directive: " + tok->str() + "( ... )";
                     outputList->push_back(err);
                 }
                 return false;

test.cpp

@@ -1831,7 +1831,7 @@ static void ifUndefFuncStyleMacro()
                         "#endif\n";
     simplecpp::OutputList outputList;
     ASSERT_EQUALS("", preprocess(code, &outputList));
-    ASSERT_EQUALS("file0,1,syntax_error,Undefined function-like macro in directive\n", toString(outputList));
+    ASSERT_EQUALS("file0,1,syntax_error,Undefined function-like macro in directive: A( ... )\n", toString(outputList));
 }
 
 static void location1()