This change does two things:
* Treats a target i386-* as if it were i686.
* Fails configure if the user is generating code
for i386.
We no longer support i386 code-generation because the i386
lacks the atomic operations we need in glibc.
You can still configure for i386-*, but you get i686 code.
You can't build with --march=i386, --mtune=i386 or a compiler
that defaults to i386 code-generation.
I've added two i386 entries in the master todo list to discuss
merging and renaming:
http://sourceware.org/glibc/wiki/Development_Todo/Master#i386
The failure modes are fail-safe here. You compile for i386,
get i686, and try to run on i386 and it fails. The configure
log has a warning saying we elided to i686. There is no situation
that I can see where we run into any serious problems.
The patch makes the current state better in that we get less
confused users and we build successfully in more default
configurations.
The next enhancement would be to add --march=i?86
as suggested in #c20 of BZ#10062 for any i?86-* builds, which
would solve the problem of a 32-bit compiler that defaults to
i386 code-gen and glibc configured for i686-* target. Which
previously failed at build time, and now will fail at configure
time (requires adding --march=i686).
Updated NEWS with BZ #10060 and #10062.
No regressions.
---
2013-04-06 Carlos O'Donell <carlos@redhat.com>
[BZ #10060, #10062]
* aclocal.m4 (LIBC_COMPILER_BUILTIN_INLINED): New macro.
* sysdeps/i386/configure.in: Use LIBC_COMPILER_BUILTIN_INLINED and
fail configure if __sync_val_compare_and_swap is not inlined.
* sysdeps/i386/configure: Regenerate.
* configure.in: Build for i686 when configured for i386.
* configure: Regenerate.
* README: Remove i386 reference.
The s390 and s390x sysdep.h files include the more generic sysdep.h.
The more generic sysdep.h defines PSEUDO. This causes an annoying
CPP warning saying the PSEUDO was redefined. This patch removes the
warning by undefining PSEUDO before the redefinition. This is in line
with what all the other machines do.
---
2013-04-06 Carlos O'Donell <carlos@redhat.com>
* sysdeps/s390/s390-32/sysdep.h: Undefine PSEUDO before redefinition.
* sysdeps/s390/s390-64/sysdep.h: Likewise.
Fixes BZ #15337.
Static builds fail with the following warning:
/home/tools/glibc/glibc/nptl/../nptl/sysdeps/unix/sysv/linux/x86_64/cancellation.S:80:
undefined reference to `__GI___pthread_unwind'
When the source is configured with --disable-hidden-plt. This is
because the preprocessor conditional in cancellation.S only checks if
the build is for SHARED, whereas hidden_def is defined appropriately
only for a SHARED build that will have symbol versioning *and* hidden
defs are enabled. The last case is false here.
Write output from the currently running benchmark into a temporary
file and move files around only once the current run is complete.
That way we don't lose data from the last two runs due to an
incomplete run.
Fix BZ #15305.
On kernel versions earlier than 2.6.29, the Linux kernel exported a
sysctl called restrict_chown for xfs, which could be used to allow
chown to users other than the owner. 2.6.29 removed this support,
causing the open_not_cancel_2 to fail and thus modify errno. The fix
is to save and restore errno so that the caller sees it as unmodified.
Additionally, since the code to check the sysctl is not useful on
newer kernels, we add an ifdef so that in future the code block gets
rmeoved completely.
Separate benchmarks for the fast and slow implementations of pow and
exp since measuring both together doesn't make sense. Adjust the
iterations for pow and exp accordingly so that they run long enough
for the measurements to be meaningful.
The branch prediction hints is actually hurts performance in this case.
The assembly implementation make two assumptions: 1. 'fabs (x) < 2^52'
is unlikely and 2. 'x > 0.0' is unlike (if 1. is true). Since it a
general floating point function, expected input is not bounded and then
it is better to let the hardware handle the branches.
Fixes BZ #15304.
The *initgroups_dyn functions are called with a group argument. This
group gid is usually skipped while populating the grouplist since the
caller adds that group id in advance.
The hesiod initgroups_dyn implementation however adds the group gid to
the list if it does not already exist. While it works fine for the
usual initgroups, it breaks nscd since it calls initgroups_dyn with -1
as the gid (to have all groups included).
The compiler is smart enough to convert those into double for powerpc,
but if we put them as doubles, it adds overhead by performing those
operations in floating point mode.
The mantissa of mp_no is intended to take only integral values. This
is a relatively good choice for powerpc due to its 4 fpus, but not for
other architectures, which suffer due to this choice. This change
makes the default mantissa a long integer and allows powerpc to
override it. Additionally, some operations have been optimized for
integer manipulation, resulting in a significant improvement in
performance.
