Fix #14181 FP nullPointerRedundantCheck / #14183 FP unusedFunction (#7873)

Co-authored-by: chrchr-github <noreply@github.com>

Author: chrchr-github

lib/tokenize.cpp

@@ -9411,6 +9411,8 @@ void Tokenizer::simplifyAttribute()
 
                 else if (Token::Match(attr, "[(,] unused|__unused__|used|__used__ [,)]")) {
                     Token *vartok = getVariableTokenAfterAttributes(tok);
+                    if (!vartok)
+                        vartok = functok;
                     if (vartok) {
                         const std::string &attribute(attr->strAt(1));
                         if (attribute.find("unused") != std::string::npos)
@@ -9526,7 +9528,7 @@ void Tokenizer::simplifyCPPAttribute()
                     head = skipCPPOrAlignAttribute(head)->next();
                 while (Token::Match(head, "%name%|::|*|&|<|>|,")) // skip return type
                     head = head->next();
-                if (head && head->str() == "(" && TokenList::isFunctionHead(head, "{;")) {
+                if (head && head->str() == "(" && (TokenList::isFunctionHead(head, "{;") || Token::simpleMatch(head->link(), ") __attribute__"))) {
                     head->previous()->isAttributeNoreturn(true);
                 }
             } else if (Token::findsimplematch(tok->tokAt(2), "nodiscard", tok->link())) {

test/testtokenize.cpp

@@ -272,7 +272,7 @@ class TestTokenizer : public TestFixture {
         TEST_CASE(functionAttributeAfter2);
         TEST_CASE(functionAttributeListBefore);
         TEST_CASE(functionAttributeListAfter);
-
+        TEST_CASE(functionAttributeListAfter2);
         TEST_CASE(cppMaybeUnusedBefore);
         TEST_CASE(cppMaybeUnusedAfter);
         TEST_CASE(cppMaybeUnusedStructuredBinding);
@@ -4197,6 +4197,25 @@ class TestTokenizer : public TestFixture {
         ASSERT(func8 && func8->isAttributeNoreturn() && func8->isAttributePure() && func8->isAttributeNothrow() && func8->isAttributeConst());
     }
 
+    void functionAttributeListAfter2() {
+        const char code[] = "[[noreturn]] void func1(const char *format, ...) __attribute__((format(printf, 1, 2)));\n" // #14181
+                            "void func2() __attribute__((unused));\n"; // #14183
+        const char expected[] = "void func1 ( const char * format , ... ) ; void func2 ( ) ;";
+
+        // tokenize..
+        SimpleTokenizer tokenizer(settings0, *this);
+        ASSERT(tokenizer.tokenize(code));
+
+        // Expected result..
+        ASSERT_EQUALS(expected, tokenizer.tokens()->stringifyList(nullptr, false));
+
+        const Token * func1 = Token::findsimplematch(tokenizer.tokens(), "func1");
+        const Token * func2 = Token::findsimplematch(tokenizer.tokens(), "func2");
+
+        ASSERT(func1 && func1->isAttributeNoreturn());
+        ASSERT(func2 && func2->isAttributeUnused());
+    }
+
     void cppMaybeUnusedBefore() {
         const char code[] = "[[maybe_unused]] int var {};";
         const char expected[] = "int var { } ;";