Re: [PATCH v2] x86: Fix x32 System V message queue syscalls

From: Florian Weimer
Date: Tue Aug 01 2023 - 03:16:09 EST

* Harald van Dijk:

> There is one complication that I think has not been mentioned yet:
> when _GNU_SOURCE is defined, glibc does provide a definition of struct
> msghdr in <sys/msg.h> with a field "__syscall_slong_t mtype;". This
> makes it slightly more likely that there is code out there in the wild
> that works fine with current kernels and would be broken by the
> fix. Given how rare x32 is, and how rare message queues are, this may
> still be acceptable, but I am mentioning it just in case this would
> cause a different approach to be preferred. And whatever is done, a
> fix should also be submitted to glibc.

What should glibc do here? Just change the definition in the header to
long and ignore the breakage?