Release/2.21

Contents

Current status
Planning
Known Issues
1. Build and test issues
2. Packaging Changes

1. Current status

The release branch of glibc-2.21 is maintained by Carlos O'Donell and its current release is 2.21 which was tagged February 6th 2015. There are no immediate plans for the next release.

The ref structure of this branch is:

release/2.21/master: main branch
glibc-2.21.N: revision releases tagged out of release/2.21/master

These people are interested in contents and further revisions tagged on the branch:

PERSON1
PERSON2
...

The general policies for release branches apply to this branch. Do you think a certain bugfix should be included in this branch?

Is the fix committed in master? It has to be, unless it's not applicable to master (e.g. code has been rewritten meantime).
Do you have commit permissions? If so, go ahead if you think it's reasonably safe. break;
Can you handle Git yourself? Then you can clone the glibc repository, cherry-pick the appropriate fixes, push your branch out and send a pull request at libc-alpha. break;
Add the glibc_2.21 keyword to the appropriate bug report.
If there is no appropriate bug report, send a request for the fix to be included to libc-alpha.

A revision release is tagged either when some critical bug-fix appears, or after some period of real-world testing, usually mainly in some SUSE distribution branch (but other distributions are welcome to run latest release/2.21/master as well, more so if they tell me about it!).

2. Planning

What things do we want to accomplish this release?

2.1. Release blockers?

Make -Wundef into an error. Completed by Joseph's turning on of -Werror
Finish -Wundef cleanup: no -Wundef warnings in build on any supported configuration. Core issues finished as of 3b566046c3e8cb252f4c0ab7b6041fef5098f1a5
Add x86 32 bit vDSO time function support
Transactional Lock Elision for PowerPC:
Fix semaphore destruction (BZ #12674) https://sourceware.org/ml/libc-alpha/2014-12/msg00155.html
powerpc64 optimized string implementations:
Fix problems with unaligned semaphores on ILP32 platforms with 64-bit atomics that require greater alignment than for long int (done for MIPS n32 and tilegx32).

2.2. Desirable this release?

Futex clean-up https://sourceware.org/ml/libc-alpha/2014-12/msg00134.html

2.3. Postpone to next release (2.22)

New POSIX-compliance fmemopen
- https://sourceware.org/ml/libc-alpha/2014-12/msg00226.html
- https://sourceware.org/ml/libc-alpha/2014-12/msg00227.html
BZ12683: pthread cancellation race condition
Intel vecotorized libm - libmvec

3. Known Issues

3.1. Build and test issues

Describe build and test issues for each architecture, or confirm a clean build with no testsuite failures. The list below is not a complete list of ABI variants; testing should try to cover the different ABI variants as far as possible.

Build system: UNAME -a, GCC?, Binutils?, Kernel ?

TRIMMED LIST OF FAILURES.

3.1.1. Architecture-independent

On systems with limited memory, stdio-common/test-vfprintf and stdio-common/bug22 may fail (bug 14231).
On some systems, a race condition may cause nptl/tst-cancel7 and nptl/tst-cancelx7 to fail (bug 14232).
If cross-testing, and the physical path to the build directory is different on the build system and the host used for testing (if it involves a symlink on one system but not the other), io/ftwtest fails.
On systems with Linux kernels before September 2011, rt/tst-cpuclock2 fails (https://sourceware.org/ml/libc-alpha/2012-02/msg00468.html). But this failure has also been reported with more recent kernels, so that kernel fix seems not to have been sufficient.
rt/tst-shm fails if /dev/shm is not mounted or does not have write permissions for the user running the tests.
If the test system does not have suitable copies of libgcc_s.so and libstdc++.so installed in system library directories, it is necessary to copy or symlink them into the build directory before testing (see https://sourceware.org/ml/libc-alpha/2012-04/msg01014.html regarding the use of system library directories here).
elf/vismain fails to build with new binutils; see bug 17711 and branch hjl/pr17711 (this terminates the test run early, so requiring make -k check to be used).
elf/check-localplt fails with new binutils; see bug 16512 and https://sourceware.org/ml/libc-alpha/2014-01/msg00626.html.

3.1.2. AArch64

LP64 LE

Build system: Linux version 3.10.55.0-1-linaro-lt-vexpress64, gcc-4.9.3 20141121, binutils 2.25.51.20141124.

FAIL: debug/tst-backtrace5
FAIL: debug/tst-backtrace6
FAIL: nptl/tst-stack4
Summary of test results:
      3 FAIL
   2165 PASS
    198 XFAIL
      4 XPASS

3.1.3. Alpha

Build system: Linux 3.16.0, gcc gentoo 4.9.2 p1.0, binutils 2.24.51, qemu 2.2.50

FAIL: conform/POSIX2008/termios.h/conform
FAIL: conform/UNIX98/termios.h/conform
FAIL: crypt/badsalttest
FAIL: debug/tst-backtrace5
FAIL: debug/tst-backtrace6
FAIL: elf/check-localplt
FAIL: math/atest-sincos
FAIL: math/test-fenv-return
FAIL: math/test-float
Summary of test results:
      9 FAIL
   2127 PASS
    128 XFAIL
     74 XPASS

3.1.4. ARM

Build system: (soft-float) GCC 4.9.3 20150124 (prerelease), binutils 2.25.51.20150124, Linux 2.6.34.1 (Joseph Myers)

FAIL: elf/check-localplt
FAIL: io/ftwtest
FAIL: math/basic-test
FAIL: nptl/tst-cancel7
FAIL: nptl/tst-cancelx7
FAIL: nptl/tst-mutexpi9
FAIL: nptl/tst-stack4
FAIL: stdio-common/bug22
FAIL: stdio-common/test-vfprintf
FAIL: stdio-common/tst-sprintf

On soft-float systems, math/basic-test fails because of GCC bug 59833.
Cause of nptl/tst-mutexpi9 and nptl/tst-stack4 failures unknown.
stdio-common/tst-sprintf failure possibly arising from limited memory available.

3.1.5. HPPA

Build system: Gentoo hppa-linux-gnu, gcc version 4.6.3 (Gentoo 4.6.3 p1.13, pie-0.5.2), Binutils (Gentoo 2.24 p1.4) 2.24, Linux 3.13.0 (Carlos O'Donell)

FAIL: conform/ISO11/stdalign.h/linknamespace
FAIL: conform/ISO11/stddef.h/conform
FAIL: conform/ISO11/stdnoreturn.h/linknamespace
FAIL: conform/ISO11/tgmath.h/conform
FAIL: conform/POSIX/aio.h/conform
FAIL: conform/POSIX/mqueue.h/conform
FAIL: conform/POSIX/pthread.h/conform
FAIL: conform/POSIX/regex.h/conform
FAIL: conform/POSIX/semaphore.h/conform
FAIL: conform/POSIX/signal.h/conform
FAIL: conform/POSIX/sys/mman.h/conform
FAIL: conform/POSIX/sys/types.h/conform
FAIL: conform/POSIX2008/aio.h/conform
FAIL: conform/POSIX2008/mqueue.h/conform
FAIL: conform/POSIX2008/pthread.h/conform
FAIL: conform/POSIX2008/regex.h/conform
FAIL: conform/POSIX2008/semaphore.h/conform
FAIL: conform/POSIX2008/spawn.h/conform
FAIL: conform/POSIX2008/sys/mman.h/conform
FAIL: conform/POSIX2008/sys/types.h/conform
FAIL: conform/UNIX98/aio.h/conform
FAIL: conform/UNIX98/ftw.h/conform
FAIL: conform/UNIX98/mqueue.h/conform
FAIL: conform/UNIX98/pthread.h/conform
FAIL: conform/UNIX98/regex.h/conform
FAIL: conform/UNIX98/semaphore.h/conform
FAIL: conform/UNIX98/sys/mman.h/conform
FAIL: conform/UNIX98/sys/types.h/conform
FAIL: conform/UNIX98/sys/uio.h/conform
FAIL: conform/XOPEN2K/ftw.h/conform
FAIL: conform/XOPEN2K/pthread.h/conform
FAIL: conform/XOPEN2K/regex.h/conform
FAIL: conform/XOPEN2K/spawn.h/conform
FAIL: conform/XOPEN2K/stdlib.h/conform
FAIL: conform/XOPEN2K/sys/mman.h/conform
FAIL: conform/XOPEN2K/sys/types.h/conform
FAIL: conform/XOPEN2K/sys/uio.h/conform
FAIL: conform/XOPEN2K8/aio.h/conform
FAIL: conform/XOPEN2K8/ftw.h/conform
FAIL: conform/XOPEN2K8/mqueue.h/conform
FAIL: conform/XOPEN2K8/pthread.h/conform
FAIL: conform/XOPEN2K8/regex.h/conform
FAIL: conform/XOPEN2K8/semaphore.h/conform
FAIL: conform/XOPEN2K8/spawn.h/conform
FAIL: conform/XOPEN2K8/stdlib.h/conform
FAIL: conform/XOPEN2K8/sys/mman.h/conform
FAIL: conform/XOPEN2K8/sys/types.h/conform
FAIL: conform/XOPEN2K8/sys/uio.h/conform
FAIL: conform/XPG4/sys/mman.h/conform
FAIL: debug/tst-backtrace2
FAIL: debug/tst-backtrace3
FAIL: debug/tst-backtrace4
FAIL: debug/tst-backtrace5
FAIL: debug/tst-backtrace6
FAIL: debug/tst-longjmp_chk2
FAIL: elf/check-execstack
FAIL: elf/check-localplt
FAIL: elf/check-textrel
FAIL: elf/tst-addr1
FAIL: elf/tst-audit2
FAIL: math/test-double
FAIL: math/test-fenv-return
FAIL: math/test-float
FAIL: math/test-idouble
FAIL: math/test-ifloat
FAIL: nptl/tst-attr3
FAIL: nptl/tst-cancel11
FAIL: nptl/tst-cancel2
FAIL: nptl/tst-cancel20
FAIL: nptl/tst-cancel21
FAIL: nptl/tst-cancel21-static
FAIL: nptl/tst-cancel22
FAIL: nptl/tst-cancel23
FAIL: nptl/tst-cancel25
FAIL: nptl/tst-cancel3
FAIL: nptl/tst-cancel4
FAIL: nptl/tst-cancel5
FAIL: nptl/tst-cancel6
FAIL: nptl/tst-cancelx11
FAIL: nptl/tst-cancelx2
FAIL: nptl/tst-cancelx20
FAIL: nptl/tst-cancelx21
FAIL: nptl/tst-cancelx3
FAIL: nptl/tst-cancelx4
FAIL: nptl/tst-cancelx5
FAIL: nptl/tst-cancelx6
FAIL: nptl/tst-cleanup4
FAIL: nptl/tst-cleanupx4
FAIL: nptl/tst-cond21
FAIL: nptl/tst-fini1
FAIL: nptl/tst-key3
FAIL: nptl/tst-sem14
FAIL: nptl/tst-signal3
FAIL: nptl/tst-stack1
FAIL: posix/tst-getcpu
FAIL: rt/tst-aio64
FAIL: rt/tst-mqueue8x
FAIL: stdlib/tst-makecontext
Summary of test results:
     98 FAIL
   2034 PASS
      1 UNRESOLVED
    201 XFAIL
      1 XPASS

3.1.6. IA64

Note: Building with gcc-4.8+ and --hash-style=gnu will create an ldso that segfaults immediately. See https://gcc.gnu.org/PR60465 for more details. You can workaround this in three ways:

build glibc with <=gcc-4.7
build glibc with -Wl,--hash-style=sysv
build glibc with this hack

Build system: ia64 Dual-Core Intel(R) Itanium(R) Processor 9040, gcc (Gentoo 4.7.4 p1.1, pie-0.5.5), GNU assembler (Gentoo 2.24 p1.4), Linux 3.14.14-gentoo. (Mike Frysinger)

FAIL: conform/POSIX2008/mqueue.h/conform
FAIL: conform/POSIX2008/sys/stat.h/conform
FAIL: conform/POSIX/signal.h/conform
FAIL: conform/POSIX/sys/stat.h/conform
FAIL: conform/POSIX/sys/wait.h/conform
FAIL: conform/UNIX98/ftw.h/conform
FAIL: conform/UNIX98/mqueue.h/conform
FAIL: conform/UNIX98/sys/stat.h/conform
FAIL: conform/XOPEN2K8/ftw.h/conform
FAIL: conform/XOPEN2K8/mqueue.h/conform
FAIL: conform/XOPEN2K8/sys/stat.h/conform
FAIL: conform/XOPEN2K/ftw.h/conform
FAIL: conform/XOPEN2K/sys/stat.h/conform
FAIL: conform/XPG4/ftw.h/conform
FAIL: debug/tst-backtrace4
FAIL: intl/tst-gettext2
FAIL: math/test-double
FAIL: math/test-fenv-return
FAIL: math/test-float
FAIL: math/test-idouble
FAIL: math/test-ifloat
FAIL: math/test-ildoubl
FAIL: math/test-ldouble
FAIL: nptl/check-abi-libpthread
FAIL: rt/tst-cpuclock2
FAIL: stdio-common/tst-long-dbl-fphex
FAIL: stdlib/tst-makecontext3
FAIL: stdlib/tst-strtod6
FAIL: time/bug-getdate1

tst-backtrace4 is known to fail on IA64 due to limited backtrace output; mailing list thread
tst-cpuclock2 seems to be flaky as it passes normally, but sometimes fails under load
makecontext is known to be limited on IA64 and the testsuite runs up against that; bug 14250
bug-getdate1 seems to be flaky as it passes normally, but sometimes fails under load
all the rest are math related and probably match some open bugs on the topic, or need some baselines updated

3.1.7. M68K

Build system: ARAnyM 1.0.2, openSUSE 13.2, gcc48-4.8.3+r218481, binutils-2.25.0, Linux 3.11.6-21-default (Andreas Schwab)

FAIL: math/basic-test
FAIL: math/test-double
FAIL: math/test-fenv
FAIL: math/test-float
FAIL: math/test-idouble
FAIL: math/test-ifloat
FAIL: math/test-ildoubl
FAIL: math/test-ldouble
FAIL: math/test-snan
FAIL: nptl/tst-sem14
FAIL: nptl/tst-tls3
FAIL: posix/tst-getaddrinfo4
FAIL: posix/tst-getaddrinfo5
FAIL: stdio-common/bug22
FAIL: stdio-common/tstdiomisc

3.1.8. MicroBlaze

3.1.9. MIPS

Build system: (soft-float) GCC 4.9.3 20150124 (prerelease), binutils 2.25.51.20150124, Linux 2.6.35.9 (Joseph Myers) - the following failures apply to both BE and LE, all of o32, n32 and n64, both hard-float and soft-float. Soft-float with GCC 4.9 and current binutils requires a GCC patch backport.

FAIL: elf/check-execstack
FAIL: elf/check-localplt
FAIL: elf/tst-audit1
FAIL: elf/tst-audit2
FAIL: elf/tst-audit8
FAIL: elf/tst-audit9
FAIL: io/ftwtest
FAIL: stdio-common/bug22
FAIL: stdio-common/test-vfprintf

Additional failures seen for hard-float o32:

FAIL: math/test-double
FAIL: math/test-float

Additional failure seen for soft-float:

FAIL: math/test-fenv

Additional failure seen for hard-float n64:

FAIL: malloc/tst-mallocfork

Additional failure seen for soft-float n32:

FAIL: nptl/tst-stack4

On soft-float MIPS systems, there is no support for floating-point exceptions and rounding modes, causing math/test-fenv to fail.
For hard-float MIPS, o32 ABI (maybe only some architecture variants), math/test-float and math/test-double fail with missing "invalid" exceptions; see bug 16399.
MIPS GCC does not use PT_GNU_STACK markers (this is a GCC issue), causing elf/check-execstack to fail (the relevant kernel support went in around February 2010).
Peculiarities of MIPS ELF cause elf/tst-audit1, elf/tst-audit2, elf/tst-audit8, elf/tst-audit9 and elf/check-localplt to fail. For the first two, see bug 2981.
The cause of the malloc/tst-mallocfork and nptl/tst-stack4 failures is unknown, likely intermittent.

3.1.10. Nios II

Build system: GCC 4.9.1, binutils 2.24.51.20140217, Linux 3.19 prerelease (Chung-Lin Tang)

FAIL: conform/symlist-stdlibs-POSIX
FAIL: conform/symlist-stdlibs-POSIX2008
FAIL: conform/symlist-stdlibs-UNIX98
FAIL: conform/symlist-stdlibs-XOPEN2K
FAIL: conform/symlist-stdlibs-XOPEN2K8
FAIL: elf/tst-rtld-load-self
FAIL: elf/tst-tls13
FAIL: iconvdata/tst-tables
FAIL: io/ftwtest
FAIL: libio/tst-memstream2
FAIL: libio/tst-wmemstream2
FAIL: localedata/cs_CZ.UTF-8/LC_CTYPE
FAIL: localedata/en_GB.UTF-8/LC_CTYPE
FAIL: localedata/tst-digits
FAIL: localedata/tst-locale
FAIL: math/atest-exp2
FAIL: math/atest-sincos
FAIL: nptl/tst-cancel7
FAIL: nptl/tst-cancelx7
FAIL: nptl/tst-eintr1
FAIL: nptl/tst-stack4
FAIL: posix/bug-regex35
FAIL: posix/tst-rxspencer
FAIL: stdio-common/bug22
FAIL: stdio-common/test-vfprintf
FAIL: stdio-common/tst-sprintf
FAIL: stdlib/tst-strtod4
FAIL: stdlib/tst-strtod5
FAIL: string/test-strcasecmp
FAIL: string/test-strncasecmp
FAIL: build stdlib/bug-getcontext.o
FAIL: build sunrpc/tst-xdrmem
FAIL: build sunrpc/tst-xdrmem2

elf/tst-rtld-load-self, and the sunrpc build fails are test environment issues.
stdlib/bug-getcontext.o build fail due to -Werror and a port with no FPU exceptions
libio and math fails are timeouts, manually verified to pass.
nptl/tst-eintr1 intermittently passes/fails
others yet to be investigated, several known for a while.

3.1.11. PowerPC (32-bit soft-float)

Build system: (soft-float) GCC 4.9.3 20150124 (prerelease), binutils 2.25.51.20150124, Linux 2.6.34.1 (Joseph Myers)

FAIL: elf/check-localplt
FAIL: io/ftwtest
FAIL: math/test-double
FAIL: math/test-float
FAIL: math/test-ildoubl
FAIL: math/test-ldouble
FAIL: rt/tst-cpuclock2
FAIL: stdio-common/bug22

test-double, test-float fail because of GCC bug 64811 causing __gcc_qadd in libgcc to generate spurious floating-point exceptions.
test-ildoubl and test-ldouble fail because of IBM long double issues.

3.1.12. PowerPC (32-bit hard-float)

Build system: Fedora 19 (POWER8), gcc version 4.9.3 (gcc-4_9-branch@217636), GNU Binutils 2.24.0.20141017 (cd3813a8c9e59c), Kernel 3.17.0-rc6 (Adhemerval Zanella)

Config options: --with-cpu=power4 --host=powerpc-linux --target=powerpc-linux --build=powerpc-linux

FAIL: math/test-ildoubl
FAIL: math/test-ldouble
FAIL: rt/tst-cpuclock2

Test math/test-ldouble:

Failure: Test: yn_upward (42, 0x8p-972)
Result:
 is:         -1.79769313486231570814e+308  -0x1.fffffffffffff0000000p+1023
 should be:  -1.79769313486231580793e+308  -0x1.fffffffffffff7ffffffp+1023
 difference:  1.79769313486231550857e+308   0x1.ffffffffffffe0000000p+1023
 ulp       :  81129638414606663681390495662080.0000
 max.ulp   :  9.0000

Test suite completed:
  73809 test cases plus 71362 tests for exception flags and
    71362 tests for errno executed.
  3050 errors occurred.

It fails due multiple IBM ldouble issues: GCC bug 59666, https://gcc.gnu.org/ml/gcc-patches/2014-01/msg00157.html

Test rt/tst-cpuclock2.out:

live thread clock fff8a8ce resolution 0.000000001
live thread before sleep => 0.000064232
self thread before sleep => 0.000191888
live thread after sleep => 0.500109582
self thread after sleep => 0.000207340
absolute clock_nanosleep on PROCESS_CPUTIME_ID 18446744073709544290 past target (outside reasonable range)
absolute clock_nanosleep on PROCESS_CPUTIME_ID slept 99992674 (outside reasonable range)

This is most likely a kernel issue, since I do not see it on powerpc64le.

3.1.13. PowerPC (64-bit hard-float)

Build system: Fedora 19 (POWER8), gcc version 4.9.3 (gcc-4_9-branch@217636), GNU Binutils 2.24.0.20141017 (cd3813a8c9e59c), Kernel 3.17.0-rc6 (Adhemerval Zanella)

Config options: --with-cpu=power4 --host=powerpc64-linux --target=powerpc64-linux --build=powerpc64-linux

FAIL: math/test-ildoubl
FAIL: math/test-ldouble
FAIL: rt/tst-cpuclock2

Test math/test-ldouble:

Failure: Test: yn_upward (42, 0x8p-972)
Result:
 is:         -1.79769313486231570814e+308  -0x1.fffffffffffff0000000p+1023
 should be:  -1.79769313486231580793e+308  -0x1.fffffffffffff7ffffffp+1023
 difference:  1.79769313486231550857e+308   0x1.ffffffffffffe0000000p+1023
 ulp       :  81129638414606663681390495662080.0000
 max.ulp   :  9.0000

Test suite completed:
  73809 test cases plus 71362 tests for exception flags and
    71362 tests for errno executed.
  3050 errors occurred.

It fails due multiple IBM ldouble issues: GCC bug 59666, https://gcc.gnu.org/ml/gcc-patches/2014-01/msg00157.html

Test rt/tst-cpuclock2.out:

live thread clock fff8a8ce resolution 0.000000001
live thread before sleep => 0.000064232
self thread before sleep => 0.000191888
live thread after sleep => 0.500109582
self thread after sleep => 0.000207340
absolute clock_nanosleep on PROCESS_CPUTIME_ID 18446744073709544290 past target (outside reasonable range)
absolute clock_nanosleep on PROCESS_CPUTIME_ID slept 99992674 (outside reasonable range)

This is most likely a kernel issue, since I do not see it on powerpc64le.

Build system: RHEL7 (POWER7), gcc version 4.8.3 20140911 (Red Hat 4.8.3-9) (GCC), Binutils 2.23.52.0.1-30.el7 20130226, Kernel 3.10.0-224.el7.ppc64 (Carlos O'Donell)

FAIL: math/test-double
FAIL: math/test-float
FAIL: math/test-ildoubl
FAIL: math/test-ldouble
Summary of test results:
      4 FAIL
   2167 PASS
    199 XFAIL
      3 XPASS

Similar failures to ppc64le below.

3.1.14. PowerPC (64-bit hard-float Little-Endian)

Build system: RHEL 7.1 Build Box, gcc version 4.8.3 20140911 (Red Hat 4.8.3-9) (GCC), GNU assembler version 2.23.52.0.1 (ppc64le-redhat-linux) using BFD version version 2.23.52.0.1-26.ael7a 20130226, Kernel 3.10.0-153.el7.ppc64le5.ppc64le (Carlos O'Donell)

FAIL: math/test-double
FAIL: math/test-float
FAIL: math/test-ildoubl
FAIL: math/test-ldouble
FAIL: posix/tst-chmod
FAIL: posix/tst-getaddrinfo5
FAIL: rt/tst-cpuclock2
Summary of test results:
      7 FAIL
   2164 PASS
    129 XFAIL
     73 XPASS

Test math/test-double:

testing double (without inline functions)
Failure: nexttoward (qNaN, 1.1): Exception "Inexact" set
Failure: nexttoward_downward (qNaN, 1.1): Exception "Inexact" set
Failure: nexttoward_towardzero (qNaN, 1.1): Exception "Inexact" set
Failure: nexttoward_upward (qNaN, 1.1): Exception "Inexact" set

Test suite completed:
  51320 test cases plus 49465 tests for exception flags and
    49465 tests for errno executed.
  4 errors occurred.

Test math/test-float:

testing float (without inline functions)
Failure: nexttoward (qNaN, 1.1): Exception "Inexact" set
Failure: nexttoward_downward (qNaN, 1.1): Exception "Inexact" set
Failure: nexttoward_towardzero (qNaN, 1.1): Exception "Inexact" set
Failure: nexttoward_upward (qNaN, 1.1): Exception "Inexact" set

Test suite completed:
  33141 test cases plus 31458 tests for exception flags and
    31458 tests for errno executed.
  4 errors occurred.

Test math/test-ildoubl:

...
Failure: Test: yn_upward (42, 0x8p-972)
Result:
 is:         -1.79769313486231570814e+308  -0x1.fffffffffffff0000000p+1023
 should be:  -1.79769313486231580793e+308  -0x1.fffffffffffff7ffffffp+1023
 difference:  1.79769313486231550857e+308   0x1.ffffffffffffe0000000p+1023
 ulp       :  81129638414606663681390495662080.0000
 max.ulp   :  9.0000

Test suite completed:
  73495 test cases plus 71036 tests for exception flags and
    71036 tests for errno executed.
  1648 errors occurred.

A lot of failures here, mostly what appear to be precision issues.

Similarly for math/test-idouble:

Failure: Test: yn_upward (42, 0x8p-972)
Result:
 is:         -1.79769313486231570814e+308  -0x1.fffffffffffff0000000p+1023
 should be:  -1.79769313486231580793e+308  -0x1.fffffffffffff7ffffffp+1023
 difference:  1.79769313486231550857e+308   0x1.ffffffffffffe0000000p+1023
 ulp       :  81129638414606663681390495662080.0000
 max.ulp   :  9.0000

Test suite completed:
  73897 test cases plus 71438 tests for exception flags and
    71438 tests for errno executed.
  3074 errors occurred.

Test posix/tst-chmod

file mode not changed to 0777 | S_ISUID | S_ISGID

Looks like a kernel bug.

Test posix/tst-getaddrinfo5

resolving "localhost." failed, skipping this hostname
resolving "www.gnu.org." worked, proceeding to test
resolving "www.gnu.org.." worked, test failed

Looks like a real bug.

Lastly rt/tst-cpuclock2.out is the ever present intermittent test that fails due to timing. That test needs review.

e.g.

live thread clock fffffffffffe50de resolution 0.000000001
live thread before sleep => 0.001486400
self thread before sleep => 0.001844110
live thread after sleep => 0.501535910
self thread after sleep => 0.001876460
absolute clock_nanosleep on process 18446744073709550418 past target (outside reasonable range)
absolute clock_nanosleep on process slept 99998802 (outside reasonable range)
absolute clock_nanosleep on PROCESS_CPUTIME_ID 18446744073709543220 past target (outside reasonable range)
absolute clock_nanosleep on PROCESS_CPUTIME_ID slept 99991604 (outside reasonable range)

3.1.15. S/390 (32-bit)

Build system: s390 GNU/Linux, gcc version 4.9.2 (GCC), (GNU Binutils) 2.24, Linux 3.14.3 (Stefan Liebler)

Summary of tests.sum results:
   2165 PASS
    199 XFAIL
      3 XPASS

FAIL: nptl/tst-setuid2
Summary of xtests.sum results:
      1 FAIL
     15 PASS

nptl/tst-setuid2 passes with root privileges.

3.1.16. S/390 (64-bit)

Build system: s390x GNU/Linux, gcc version 4.9.2 (GCC), (GNU Binutils) 2.24, Linux 3.14.3 (Stefan Liebler)

Summary of test results:
   2166 PASS
    194 XFAIL
      8 XPASS

FAIL: nptl/tst-setuid2
Summary of test results for extra tests:
      1 FAIL
     15 PASS

nptl/tst-setuid2 passes with root privileges.

Build system: RHEL 7.0, gcc version 4.8.2 20140120 (Red Hat 4.8.2-16) (GCC), (GNU Binutils) 2.24, Linux 3.10.0-123.el7.s390x (Carlos O'Donell)

Summary of test results:
   2165 PASS
      1 UNRESOLVED
    198 XFAIL
      4 XPASS

3.1.17. SH

Build system: Fedora 20, cross gcc 4.6.4, BFD version 2.23.52, Linux 3.18.0 (Kazumoto Kojima)

FAIL: conform/ISO11/stdalign.h/linknamespace
FAIL: conform/ISO11/stdnoreturn.h/linknamespace
FAIL: crypt/sha256c-test
FAIL: csu/tst-atomic
FAIL: csu/tst-atomic-long
FAIL: elf/check-localplt
FAIL: elf/tst-tls13
FAIL: iconvdata/mtrace-tst-loading
FAIL: iconvdata/tst-loading
FAIL: io/ftwtest
FAIL: libio/tst-fopenloc
FAIL: libio/tst-fopenloc-cmp
FAIL: libio/tst-fopenloc-mem
FAIL: libio/tst-memstream2
FAIL: libio/tst-wmemstream2
FAIL: localedata/mtrace-tst-leaks
FAIL: localedata/tst-leaks
FAIL: localedata/tst-setlocale3
FAIL: malloc/tst-calloc
FAIL: malloc/tst-trim1
FAIL: math/atest-exp2
FAIL: math/atest-sincos
FAIL: math/basic-test
FAIL: math/bug-nextafter
FAIL: math/bug-nexttoward
FAIL: math/test-double
FAIL: math/test-fenv
FAIL: math/test-float
FAIL: math/test-idouble
FAIL: math/test-ifloat
FAIL: math/test-misc
FAIL: nptl/tst-stack4
FAIL: nptl/tst-umask1
FAIL: nss/test-netdb
FAIL: posix/bug-regex24
FAIL: posix/tst-fnmatch
FAIL: posix/tst-fnmatch-mem
FAIL: posix/tst-getaddrinfo5
FAIL: posix/tst-getcpu
FAIL: posix/tst-regex2
FAIL: setjmp/tst-setjmp-fp
FAIL: stdio-common/bug22
FAIL: stdio-common/test-vfprintf
FAIL: stdio-common/tst-sprintf
FAIL: stdlib/tst-strtod-overflow
FAIL: string/stratcliff
FAIL: wcsmbs/wcsatcliff
Summary of test results:
     47 FAIL
   1693 PASS
     78 XFAIL

3.1.18. SPARC (32-bit)

3.1.19. SPARC (64-bit)

3.1.20. TILE-Gx (64- and 32-bit)

Build system: CentOS 6.3, but with gcc 4.8.2, binutils 2.25, kernel 3.10.53. (Chris Metcalf)

FAIL: nptl/tst-cancel24
FAIL: nptl/tst-cancel24-static
FAIL: nptl/tst-cancelx16
FAIL: nptl/tst-cancelx17
FAIL: nptl/tst-cancelx18
FAIL: nptl/tst-cancelx20
FAIL: nptl/tst-cancelx21
FAIL: nptl/tst-cancelx4
FAIL: nptl/tst-cancelx5
FAIL: nptl/tst-cleanupx0
FAIL: nptl/tst-cleanupx1
FAIL: nptl/tst-cleanupx3
FAIL: nptl/tst-cleanupx4
FAIL: nptl/tst-oncex3
FAIL: nptl/tst-oncex4
FAIL: rt/tst-mqueue8x

The failures are due to bug 14266

3.1.21. TILEPro

3.1.22. x86 (32-bit, Linux)

Build system: Fedora 21 Build Box, gcc version 4.9.2 20141101 (Red Hat 4.9.2-1) (GCC) , GNU assembler version 2.24 (x86_64-redhat-linux) using BFD version version 2.24, Kernel 3.17.8-300.fc21.x86_64. (Carlos O'Donell)

FAIL: math/test-float
Summary of test results:
      1 FAIL
   2169 PASS
      1 UNRESOLVED
    198 XFAIL
      4 XPASS

The test float errors are all ERANGE failures:

testing float (without inline functions)
Failure: exp10 (-0x1.31p+8): errno set to 0, expected 34 (ERANGE)
Failure: exp10 (-0x1.344p+12): errno set to 0, expected 34 (ERANGE)
Failure: exp10_downward (-0x1.31p+8): errno set to 0, expected 34 (ERANGE)
Failure: exp10_downward (-0x1.344p+12): errno set to 0, expected 34 (ERANGE)
Failure: exp10_towardzero (-0x1.31p+8): errno set to 0, expected 34 (ERANGE)
Failure: exp10_towardzero (-0x1.344p+12): errno set to 0, expected 34 (ERANGE)
Failure: exp2 (-0x4.01p+12): errno set to 0, expected 34 (ERANGE)
Failure: exp2 (-0x4.32p+8): errno set to 0, expected 34 (ERANGE)
Failure: exp2_downward (-0x4.01p+12): errno set to 0, expected 34 (ERANGE)
Failure: exp2_downward (-0x4.32p+8): errno set to 0, expected 34 (ERANGE)
Failure: exp2_towardzero (-0x4.01p+12): errno set to 0, expected 34 (ERANGE)
Failure: exp2_towardzero (-0x4.32p+8): errno set to 0, expected 34 (ERANGE)
Failure: pow10 (-0x1.31p+8): errno set to 0, expected 34 (ERANGE)
Failure: pow10 (-0x1.344p+12): errno set to 0, expected 34 (ERANGE)
Failure: pow10_downward (-0x1.31p+8): errno set to 0, expected 34 (ERANGE)
Failure: pow10_downward (-0x1.344p+12): errno set to 0, expected 34 (ERANGE)
Failure: pow10_towardzero (-0x1.31p+8): errno set to 0, expected 34 (ERANGE)
Failure: pow10_towardzero (-0x1.344p+12): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x1.86a08p+16): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x1.f3fffep+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x1.f40002p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x2.9ffffcp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x2.a00004p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x2.edfffcp+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x2.ee0004p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x3.1ffffcp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x3.200004p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x3.e7fffcp+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x3.e80004p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x4.e1fff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x4.e20008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x5.dbfff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x5.dc0008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.3ffff8p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.400008p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.d5fff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.d60008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.e2fff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.e30008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.e3fff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.e40008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.e4fff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.e50008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.e5fff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.e60008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.ebfff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.ec0008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.ecfff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.ed0008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.edfff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.ee0008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.eefff8p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x6.ef0008p+8): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x9.5ffffp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0x9.60001p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xa.c0001p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.4ffffp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.50001p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.5ffffp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.60001p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.6ffffp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.70001p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.7ffffp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.80001p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.bffffp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.c0001p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.cffffp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.d0001p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.dffffp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.e0001p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.effffp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xb.f0001p+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xf.9ffffp+4): errno set to 0, expected 34 (ERANGE)
Failure: tgamma (-0xf.a0001p+4): errno set to 0, expected 34 (ERANGE)

Test suite completed:
  33061 test cases plus 31378 tests for exception flags and
    31378 tests for errno executed.
  74 errors occurred.

Need to investigate these.

3.1.23. x86_64 (64-bit, Linux)

Summary of test results:
   2184 PASS
      1 UNRESOLVED
    199 XFAIL
      3 XPASS

3.1.24. x86_64 (x32, Linux)

Build system: Fedora 21/x86-64, gcc version 4.9.2 20150107 (Red Hat 4.9.2-5) (GCC) , GNU binutils 2.25.51.20150123, Kernel 3.18.3-201.fc21.x86_64. (H.J. Lu)

FAIL: elf/check-localplt
FAIL: elf/tst-leaks1-mem
FAIL: nptl/tst-robust8
FAIL: nptl/tst-sem1
FAIL: nptl/tst-sem14
FAIL: rt/tst-mqueue5
Summary of test results:
      6 FAIL
   1785 PASS
     76 XFAIL 
      2 XPASS

FAIL: nptl/tst-setuid2
Summary of test results for extra tests:
      1 FAIL
     15 PASS

3.1.25. x86 (32-bit, Hurd)

3.2. Packaging Changes

Describe any distribution packing changes that may be required.

3.2.1. Minimum required gcc version increased to 4.6

The minimum GCC version that can be used to build this version of the GNU C Library is GCC 4.6. Older GCC versions, and non-GNU compilers, can still be used to compile programs using the GNU C Library.

3.2.2. -Werror is enabled by default

The -Werror compiler flag in now enabled by default when building glibc. Although most warnings when building have been addressed, you may need to pass "--disable-werror" to configure when building with a toolchain combination that was untested by the developers.

3.2.3. Function sigvec removed

The obsolete function sigvec has been removed form the public API. New applications cannot be built with sigvec. Existing applications have binary compatibility guaranteed and will operate correctly.