lucvoo / sparse Goto Github PK

In the context of git development (cf. https://lore.kernel.org/git/[email protected]), we saw that sparse (built from the tip, v0.6.4-66-g0196afe1) barfs with this declaration of regexec from glibc:

    extern int regexec (const regex_t *_Restrict_ __preg,
                        const char *_Restrict_ __String, size_t __nmatch,
                        regmatch_t __pmatch[_Restrict_arr_
                                            _REGEX_NELTS (__nmatch)],
                        int __eflags);

which (with macros that depend on compiler versions stripped) boils down to have either

    regmatch_t __pmatch[restrict __nmatch]

or

    regmatch_t __pmatch[__nmatch]

and gives

/usr/include/regex.h:682:41: error: undefined identifier '__nmatch'
/usr/include/regex.h:682:41: error: bad constant expression type

It seems that sparse can grok vla as a local variable (e.g. pre-process.c:expand() of sparse itself does have args[nargs] on stack, and make selfcheck does pass -Wno-vla), but does it understand vla as a parameter into a function? If it does not yet, any plans?

Or am I diagnosing the issue incorrectly and there is something else going on?

Thanks.

I doubt anyone pays attention to this issue tracker but just in case:

• zephyrproject-rtos/zephyr#63003

Commit 3f5a1da introduced a verification in blob_free that I don't understand the motive and there is no comment about it. Do you known why is it there?

best regards,
--ctarbide