Re: [PATCH 2/2] util: Consolidate and improve workarounds for clang-tidy issue 58992

[Stefano Brivio <sbrivio@redhat.com>]

On Fri, 15 Sep 2023 16:43:37 +1000
David Gibson <david@gibson.dropbear.id.au> wrote:

> We have several workarounds for a clang-tidy bug where the checker doesn't
> recognize that a number of system calls write to - and therefore initialise
> - a socket address.  We can't neatly use a suppression, because the bogus
> warning shows up some time after the actual system call, when we access
> a field of the socket address which clang-tidy erroneously thinks is
> uninitialised.
> 
> Consolidate these workarounds into one place by using macros to implement
> wrappers around affected system calls which add a memset() of the sockaddr
> to silence clang-tidy.  This removes the need for the individual memset()
> workarounds at the callers - and the somewhat longwinded explanatory
> comments.
> 
> We can then use a #define to not include the hack in "real" builds, but
> only consider it for clang-tidy.

I'm probably missing something, but wouldn't it be more obvious to
conditionally define the wrapper itself? That is,

#ifdef CLANG_TIDY_58992
# define recvfrom(s, buf, len, flags, src, addrlen)		\
	wrap_recvfrom((s), (buf), (len), (flags), (src), (addrlen))
#endif

instead of doing that in sa_init()?

-- 
Stefano