[Python-Dev] what environment variable should contain compiler warning suppression flags?

[Mark Dickinson]

On Mon, Jun 28, 2010 at 12:38 PM, M.-A. Lemburg <mal at egenix.com> wrote:
>> On Sun, Jun 27, 2010 at 13:37, Jeffrey Yasskin <jyasskin at gmail.com> wrote:
>>> On Sun, Jun 27, 2010 at 1:04 PM, Mark Dickinson <dickinsm at gmail.com> wrote:
>>>> I'm not sure I understand the importance of allowing AC_PROG_CC to set
>>>> CFLAGS (if CFLAGS is undefined at the point of the AC_PROG_CC);  can
>>>> someone give an example of why this is necessary?
>>>
>>> Marc-Andre's argument seems to be "it's possible that AC_PROG_CC adds
>>> other flags as well (it currently doesn't, but that may well change in
>>> future versions of autoconf)." That seems a little weak to constrain
>>> fixing actual problems today. If it ever adds more arguments, we'll
>>> need to inspect them anyway to see if they're more like -g or -O2
>>> (wanted or harmful).
>
> Please see the discussion on the ticket for details.

Yes, I've done that.  It's repeatedly asserted in that discussion that
AC_PROG_CC should be allowed to initialize an otherwise empty CFLAGS,
but nowhere in that discussion does it explain *why* this is
desirable.  What would be so bad about not allowing AC_PROG_CC to
initialize CFLAGS?  (E.g., by setting an otherwise empty CFLAGS to
'-g' before the AC_PROG_CC invocation.)  That would fix the issue of
the unwanted -O2 flag that AC_PROG_CC otherwise adds.

Mark