[PATCH 2.19] S/390: Make ucontext_t extendible - update

[Joseph S. Myers]

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