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RE: [COMMITTED] Fix GCC6 build errors due to unused statics
- From: Joseph Myers <joseph at codesourcery dot com>
- To: Wilco Dijkstra <wdijkstr at arm dot com>
- Cc: 'GNU C Library' <libc-alpha at sourceware dot org>
- Date: Fri, 18 Sep 2015 21:19:45 +0000
- Subject: RE: [COMMITTED] Fix GCC6 build errors due to unused statics
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On Fri, 18 Sep 2015, Wilco Dijkstra wrote:
> OK, I've reverted the private.h change and changed timezone/Makefile instead
> (see below).
I take it you made sure the -Wno-error= options work with GCC versions
that don't have the new warning option?
> I'd like to ensure GLIBC remains buildable with up to date GCC versions -
That doesn't affect anything I said. In the GNU Project we need to work
out the appropriate place to fix things involving more than one project
rather than jumping to conclusions about which place to change. And in
glibc changes need consensus - the fact that something fixes a warning
with new GCC does not make it (in general - unused variables in
glibc-local code are a reasonable exception) an obvious fix that can
bypass the process of obtaining consensus (which includes considering
whether the warning should actually be in -Wall at all, and which of
possibly several approaches to a fix in glibc makes the most sense if
fixing in glibc).
glibc releases should be buildable with GCC releases. It's expected that
there will often be breakage with GCC development versions that will take
time to reach consensus on a fix.
> If it hasn't been decided which warnings to enable in GCC6 (sorry I haven't
> followed all the discussions...) then maybe we should not use -Werror at all
> when building GLIBC with trunk GCC and only print warnings until all this has
> been decided and any issues fixed.
If you want to detect glibc regressions, you should be building glibc with
stable binutils and GCC versions. If you want to detect regressions in
GCC, upgrade GCC while keeping the versions of the other projects fixed.
If you find such a regression in GCC (new GCC no longer builds a glibc
version older GCC built) then you get to seek consensus about the right
fix. Upgrading more than one component at a time means it may be less
clear which component a regression is in.
--
Joseph S. Myers
joseph@codesourcery.com