Internal error when checking for unused functions

[Pedro Navarro]

cppcheck 2.6.1 reports error: Internal error. Token::linkAt called with index outside the tokens range. [cppcheckError]. This didn't happen in 2.5.

I narrowed it down to this:

void text(std::function<void()> function)
{
    std::unique_ptr<std::function<void()>> x;
}

The problem seems to be because the textfunction has a parameter named function which seems to collide with the std::function parameter type passed to std::unique_ptr. If I rename the parameter so it's not called "function" , like void text(std::function<void()> foonction) then cppcheck doesn't report an internal error.

In checkunusedfunctions.cpp when the next token is < then ftok = ftok->link() is called, but the value of mNextseems to be invalid or null, as the following call to Token::Match prints the error.

        // funcname ( => Assert that the end parentheses isn't followed by {
        if (Token::Match(funcname, "%name% (|<")) {
            const Token *ftok = funcname->next();
            if (ftok->str() == "<")
                ftok = ftok->link();
            if (Token::Match(ftok->linkAt(1), ") const|throw|{"))
                funcname = nullptr;
        }

Pedro

[Daniel Marjamäki]

Thanks!
cppcheck-2.6 crashes for me with a segmentation fault. I do not get any crash in cppcheck HEAD but I wonder if the bug is fixed . Need to investigate a bit why I don't get the crash with head.

[Pedro Navarro]

It used to crash for me, too (I got an Internal error, received signal 11) but it was mostly when I was calling cppcheck with -j20. To debug the problem I isolated the problematic file and that's when I saw the "Internal error: linkat called with index outside the tokens range".