Re: AC_CHECK_FUNC not safe WRT link time optimizing compilers

[Ralf Wildenhues]

Hello Jan,

* Jan Hubicka wrote on Mon, Oct 25, 2010 at 08:39:07PM CEST:
> AC_CHECK_FUNC produce test like the following:
> char pstat_getstatic ();
> char (*f) () = pstat_getstatic;
> int
> main ()
> {
>   return f != pstat_getstatic;
> }

Not since Autoconf 2.60 or newer, see
<http://git.savannah.gnu.org/cgit/autoconf.git/commit/?id=f50d0bd4c7d92fbabcd9169920a23889524790e7>

from 5 years ago.  Of course we cannot fix old Autoconf releases.

Where and how did you find the above test code though?

> See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46055

BTW (regarding comment 7), turning off specific compiler flags for some
configure tests is not going to fly (i.e., it is a bad and
maintenance-intensive hack), as the whole idea is to test things in the
same manner as execution happens later.

Hope that helps.

Cheers,
Ralf