This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: [PATCH 2.19] S/390: Make ucontext_t extendible - update
- From: "Joseph S. Myers" <joseph at codesourcery dot com>
- To: Andreas Krebbel <krebbel at linux dot vnet dot ibm dot com>
- Cc: <libc-alpha at sourceware dot org>, Kaz Kojima <kkojima at rr dot iij4u dot or dot jp>
- Date: Wed, 22 Jan 2014 03:23:59 +0000
- Subject: Re: [PATCH 2.19] S/390: Make ucontext_t extendible - update
- Authentication-results: sourceware.org; auth=none
- References: <20140103154754 dot GB30732 at bart>
On Fri, 3 Jan 2014, Andreas Krebbel wrote:
> * sysdeps/unix/sysv/linux/s390/sys/ucontext.h: Split into 32 and
> 64 bit versions:
I've just noticed this change. Splitting a header like this is a bad
idea: the same set of installed headers should be usable for multilib
configurations, meaning that headers should contain 32-bit/64-bit
preprocessor conditionals instead of having different versions of the
header installed for different glibc configurations on the same
architecture.
(The same applies to hard/soft float variations, and to variants within
the same architecture. Pre-existing cases of such undesirable separate
copies of installed headers include m68k / coldfire bits/fenv.h and
bits/mathinline.h, SH fpu_control.h, and SH sys/ucontext.h - I don't know
if the last means SH3 and SH4 are in fact incompatible glibc ABIs, or if
there are SH configurations supported for glibc that are neither SH3 nor
SH4 and so get sysdeps/sh/sys/ucontext.h and if that gives yet another
incompatible ABI - not that the sysdeps/sh file looks likely to be right
for Linux anyway, and README doesn't mention other SH as supported.)
--
Joseph S. Myers
joseph@codesourcery.com