Partial fix for #11638 Library::getFunctionName: SIGSEGV (#4920)

* Partial fix for #11638 Library::getFunctionName: SIGSEGV

* Fix test

* simpleMatch()

Author: chrchr-github

lib/tokenize.cpp

@@ -8044,6 +8044,8 @@ void Tokenizer::findGarbageCode() const
             if (!isCPP() || mSettings->standards.cpp < Standards::CPP20 || !Token::Match(tok->previous(), "%name% : %num% ="))
                 syntaxError(tok, tok->next()->str() + " " + tok->strAt(2));
         }
+        else if (Token::simpleMatch(tok, ") return") && !Token::Match(tok->link()->previous(), "if|while|for ("))
+            syntaxError(tok);
 
         if (tok->isControlFlowKeyword() && Token::Match(tok, "if|while|for|switch")) { // if|while|for|switch (EXPR) { ... }
             if (tok->previous() && !Token::Match(tok->previous(), "%name%|:|;|{|}|)")) {

test/testtokenize.cpp

@@ -6782,6 +6782,8 @@ class TestTokenizer : public TestFixture {
 
         ASSERT_THROW_EQUALS(tokenizeAndStringify("enum : { };"), InternalError, "syntax error: Unexpected token '{'");
         ASSERT_THROW_EQUALS(tokenizeAndStringify("enum : 3 { };"), InternalError, "syntax error: Unexpected token '3'");
+
+        ASSERT_THROW_EQUALS(tokenizeAndStringify("int a() { b((c)return 0) }"), InternalError, "syntax error");
     }