Re: RFC PATCH: Overhaul AC_TYPE_GETGROUPS and AC_FUNC_GETGROUPS.

On 2023-04-02 12:42, Zack Weinberg wrote:

> Cross-referencing gnulib’s getgroups.m4 I see that there *are*
> current-generation Unixes with bugs in getgroups that are worth
> worrying about (notably, FreeBSD mishandles an error case even in
> CURRENT). 

That error case is not very important, as calling getgroups with a 
negative size) since programs are not likely to exercise it. The really 
serious failures are for long-dead systems (Ultrix 4.3, NextSTEP 3.2) 
that we no longer need to worry about.

AC_FUNC_GETGROUPS has been documented as being obsolescent since 
Autoconf 2.70 (2020). I think changing it to report a failure on macOS 
and FreeBSD is more likely to cause problems than cure them. So I 
instead that we instead either leave it alone, or merely add an 
obsoletion notice, or (if we want to be more dramatic) replace it with 
something that merely tests whether the function has the correct 
prototype and links properly.