This patch removes the socket.S implementation for all ports and replace
it by a C implementation using socketcall. For ports that implement
the syscall directly, there is no change.
The patch idea is to simplify the socket function implementation that
uses the socketcall to be based on C implemetation instead of a pseudo
assembly implementation with arch specific parts. The patch then remove
the assembly implementatation for the ports which uses socketcall
(i386, microblaze, mips, powerpc, sparc, m68k, s390 and sh).
I have cross-build GLIBC for afore-mentioned ports and tested on both
i386 and ppc32 without regressions.
This patch is glibc support for a PowerPC TLS optimization, inspired
by Alexandre Oliva's TLS optimization for other processors,
http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
In essence, this optimization uses a zero module id in the tls_index
GOT entry to indicate that a TLS variable is allocated space in the
static TLS area. A special plt call linker stub for __tls_get_addr
checks for such a tls_index and if found, returns the offset
immediately. The linker communicates the fact that the special
__tls_get_addr stub is used by setting a bit in the dynamic tag
DT_PPC64_OPT/DT_PPC_OPT. glibc communicates to the linker that this
optimization is available by the presence of __tls_get_addr_opt.
tst-tlsmod2.so is built with -Wl,--no-tls-get-addr-optimize for
tst-tls-dlinfo, which otherwise would fail since it tests that no
static tls is allocated. The ld option --no-tls-get-addr-optimize has
been available since binutils-2.20 so doesn't need a configure test.
* NEWS: Advertise TLS optimization.
* elf/elf.h (R_PPC_TLSGD, R_PPC_TLSLD, DT_PPC_OPT, PPC_OPT_TLS): Define.
(DT_PPC_NUM): Increment.
* elf/dynamic-link.h (HAVE_STATIC_TLS): Define.
(CHECK_STATIC_TLS): Use here.
* sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela): Optimize
TLS descriptors.
* sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/powerpc/dl-tls.c: New file.
* sysdeps/powerpc/Versions: Add __tls_get_addr_opt.
* sysdeps/powerpc/tst-tlsopt-powerpc.c: New tls test.
* sysdeps/unix/sysv/linux/powerpc/Makefile: Add new test.
Build tst-tlsmod2.so with --no-tls-get-addr-optimize.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist: Update.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/ld.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/ld-le.abilist: Likewise.
With AIX port deprecated there is no need to check/define
HAVE_ASM_GLOBAL_DOT_NAME anymore since the current minimum binutils
supported (2.22) does not emit global symbol with dot.
This patch removes all the HAVE_ASM_GLOBAL_DOT_NAME definition and
checks for powerpc64 port.
posix_spawn (a standard POSIX function) brings in a use of getrlimit64
(not a standard POSIX function). This patch fixes this by using
__getrlimit64 and making getrlimit64 a weak alias.
This is more complicated than some such changes because of files that
define getrlimit64 in their own way using symbol versioning after
including the main sysdeps/unix/sysv/linux/getrlimit64.c with a
getrlimit macro defined. There are various existing patterns for such
cases in glibc; the one I've used here is that a getrlimit64 macro
disables the weak_alias / libc_hidden_weak calls, leaving it to the
including file to define the getrlimit64 name in whatever way is
appropriate.
Tested for x86_64 and x86 that installed stripped shared libraries are
unchanged by this patch.
[BZ #17991]
* include/sys/resource.h (__getrlimit64): Declare. Use
libc_hidden_proto.
* resource/getrlimit64.c (getrlimit64): Rename to __getrlimit64
and define as weak alias of __getrlimit64. Use libc_hidden_weak.
* sysdeps/posix/spawni.c (__spawni): Call __getrlimit64 instead of
getrlimit64.
* sysdeps/unix/sysv/linux/getrlimit64.c (getrlimit64): Rename to
__getrlimit64.
[!getrlimit64] (getrlimit64): Define as weak alias of
__getrlimit64. Use libc_hidden_weak.
* sysdeps/unix/sysv/linux/i386/getrlimit64.c (getrlimit64): Define
using __getrlimit64 not __new_getrlimit64.
(__GI_getrlimit64): Likewise.
* sysdeps/unix/sysv/linux/mips/getrlimit64.c (getrlimit64):
Likewise.
(__GI_getrlimit64): Likewise.
(__old_getrlimit64): Use __getrlimit64 not __new_getrlimit64.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/syscalls.list
(getrlimit): Add __getrlimit64 alias.
* sysdeps/unix/sysv/linux/wordsize-64/syscalls.list (getrlimit):
Likewise.
* conform/Makefile (test-xfail-XOPEN2K/spawn.h/linknamespace):
Remove variable.
(test-xfail-POSIX2008/spawn.h/linknamespace): Likewise.
(test-xfail-XOPEN2K8/spawn.h/linknamespace): Likewise.
Linux kernel powerpc documentation states issuing a syscall inside a
transaction is not recommended and may lead to undefined behavior. It
also states syscalls does not abort transactoin neither they run in
transactional state.
To avoid side-effects being visible outside transactions, GLIBC with
lock elision enabled will issue a transaction abort instruction just
before all syscalls if hardware supports hardware transactions.
For maximum paranoia we run ld.so through the normal set
of tests for all of the shared libraries. This includes
running ld.so through check-localplt, check-textrel, and
check-execstack. While none of these should trigger any
failures given the way ld.so is built, it might possibly
fail if a developer does something wrong. This paranoia
was triggered by a discussion over the use of __strcpy
vs. strcpy [1] and if the symbol could leak and use the
libc.so version.
The check-localplt test fails right away because localplt.data
needs updating for all arches. By default we add 6 new symbols:
__tls_get_addr, __libc_memalign, malloc, calloc, realloc and
free. Other machines like i386, power, and s390 require some
different symbol sets e.g. ___tls_get_addr vs. __tls_get_addr
for i386.
Verified for i386
Verified for x86_64
Verified for ppc32
Verified for ppc64
Verified for ppc64le
Verified for arm
Verified for aarch64
Verified for s390
Verified for s390x
Guessed for alpha
Guessed for ia64
Guessed for m68k
Guessed for microblaze
Guessed for sparc32
Guessed for sparc64
Defaults for sh
Defaults for mips
Defaults for hppa
Defaults for tile
Machine manintainers notified to double check the data
used in localplt.data.
[1] https://sourceware.org/ml/libc-alpha/2014-10/msg00548.html
Concluding the move of syscall definitions to syscalls.list, where the
removal of support for old kernel versions has made this possible,
this patch removes C definitions of pread, pread64, pwrite and
pwrite64 for powerpc64. As far as I can tell, the existing
syscalls.list definitions in
sysdeps/unix/sysv/linux/wordsize-64/syscalls.list should suffice to
produce results equivalent to what these C files do.
[BZ #14138]
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pread.c: Remove file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pread64.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pwrite.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/pwrite64.c: Likewise.
When a shlib-versions file has a DEFAULT line, it's not necessary to
specify the same default minimum symbol version on the lines for
individual libraries. If those lines otherwise duplicate the default
SONAME for the library in question, they can be removed completely.
This patch makes such cleanups: version entries for ld.so are removed
(leaving just the definition of the architecture-specific dynamic
linker name) and entries for libpthread are removed completely (since
the default is libpthread.so.0).
Tested for x86_64 that the installed shared libraries are unchanged by
this patch.
There are various architectures (hppa, ia64, mips, sh, sparc64) that
define minimum symbol versions (or in the case of mips, omission of
symbol versions) only for particular libraries without a DEFAULT line.
None of these are equivalent to something simpler with a DEFAULT line
because all have some other libraries, not explicitly mentioned, with
symbol versions that would be omitted were such a line used. In the
mips case I'm pretty sure it was a mistake not to omit the 2.1 symbols
for libthread_db; for the others I don't know if it was a mistake or
deliberate that some symbols in various libraries have 2.0 or 2.1
versions despite other libraries having a 2.2 minimum.
This concludes the shlib-versions cleanups I'm aware of.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/shlib-versions: Do not
specify symbol version for ld.so. Do not include entry for
libpthread.
* sysdeps/unix/sysv/linux/s390/s390-64/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/shlib-versions: Likewise.
This patch eliminates the mixture of SONAME information in
shlib-versions files and SONAME information used to generate
gnu/lib-names.h in makefiles, with the information in the makefiles
being removed so all this information comes from the shlib-versions
files.
So that gnu/lib-names.h supports multiple ABIs, it is changed to be
generated on the same basis as gnu/stubs.h: when there are multiple
ABIs, gnu/lib-names.h is a wrapper header (the same header installed
whatever ABI is being built) and separate headers such as
gnu/lib-names-64.h contain the substantive contents (only one such
header being installed by any glibc build).
The rules for building gnu/lib-names.h were moved from Makeconfig to
Makerules because they need to come after sysdeps makefiles are
included (now that "ifndef abi-variants" is a toplevel conditional on
the rules rather than $(abi-variants) being evaluated later inside the
commands for a rule).
Tested for x86_64 and x86 that the installed shared libraries are
unchanged by this patch, and examined the installed gnu/lib-names*.h
headers by hand. Also tested the case of a single ABI (where there is
just a single header installed, again like stubs.h) by hacking
abi-variants to empty for x86_64.
[BZ #14171]
* Makeconfig [$(build-shared) = yes]
($(common-objpfx)soversions.mk): Don't handle SONAMEs specified in
makefiles.
[$(build-shared) = yes && $(soversions.mk-done) = t]
($(common-objpfx)gnu/lib-names.h): Remove rule.
[$(build-shared) = yes && $(soversions.mk-done) = t]
($(common-objpfx)gnu/lib-names.stmp): Likewise. Split and moved
to Makerules.
[$(build-shared) = yes && $(soversions.mk-done) = t]
(before-compile): Don't append $(common-objpfx)gnu/lib-names.h
here.
[$(build-shared) = yes && $(soversions.mk-done) = t]
(common-generated): Don't append gnu/lib-names.h and
gnu/lib-names.stmp here.
* Makerules [$(build-shared) = yes && $(soversions.mk-done) = t]
(lib-names-h-abi): New variable.
[$(build-shared) = yes && $(soversions.mk-done) = t]
(lib-names-stmp-abi): Likewise.
[$(build-shared) = yes && $(soversions.mk-done) = t &&
abi-variants] (before-compile): Append
$(common-objpfx)$(lib-names-h-abi).
[$(build-shared) = yes && $(soversions.mk-done) = t &&
abi-variants] (common-generated): Append gnu/lib-names.h.
[$(build-shared) = yes && $(soversions.mk-done) = t &&
abi-variants] (install-others-nosubdir): Depend on
$(inst_includedir)/$(lib-names-h-abi).
[$(build-shared) = yes && $(soversions.mk-done) = t &&
abi-variants] ($(common-objpfx)gnu/lib-names.h): New rule.
[$(build-shared) = yes && $(soversions.mk-done) = t]
($(common-objpfx)$(lib-names-h-abi)): New rule.
[$(build-shared) = yes && $(soversions.mk-done) = t]
($(common-objpfx)$(lib-names-stmp-abi)): Likewise.
[$(build-shared) = yes && $(soversions.mk-done) = t]
(common-generated): Append $(lib-names-h-abi) and
$(lib-names-stmp-abi).
* scripts/lib-names.awk: Do not handle multi being set.
* sysdeps/unix/sysv/linux/aarch64/Makefile (abi-lp64-ld-soname):
Remove variable.
(abi-lp64_be-ld-soname): Likewise.
* sysdeps/unix/sysv/linux/arm/Makefile (abi-soft-ld-soname):
Likewise.
(abi-hard-ld-soname): Likewise.
* sysdeps/unix/sysv/linux/i386/shlib-versions: New file.
* sysdeps/unix/sysv/linux/mips/Makefile (abi-o32_soft-ld-soname):
Remove variable.
(abi-o32_hard-ld-soname): Likewise.
(abi-o32_soft_2008-ld-soname): Likewise.
(abi-o32_hard_2008-ld-soname): Likewise.
(abi-n32_soft-ld-soname): Likewise.
(abi-n32_hard-ld-soname): Likewise.
(abi-n32_soft_2008-ld-soname): Likewise.
(abi-n32_hard_2008-ld-soname): Likewise.
(abi-n64_soft-ld-soname): Likewise.
(abi-n64_hard-ld-soname): Likewise.
(abi-n64_soft_2008-ld-soname): Likewise.
(abi-n64_hard_2008-ld-soname): Likewise.
* sysdeps/unix/sysv/linux/powerpc/Makefile (abi-64-v1-ld-soname):
Likewise.
(abi-64-v2-ld-soname): Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/shlib-versions: Add
ld.so entries.
* sysdeps/unix/sysv/linux/s390/Makefile (abi-64-ld-soname): Remove
variable.
* sysdeps/unix/sysv/linux/s390/s390-64/shlib-versions: Add ld.so
entry.
* sysdeps/unix/sysv/linux/x86/Makefile (abi-32-ld-soname): Remove
variable.
(abi-64-ld-soname): Likewise.
(abi-x32-ld-soname): Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/shlib-versions: Add ld.so
entry.
* sysdeps/unix/sysv/linux/x86_64/x32/shlib-versions: Likewise.
This patch removes the first column (patterns matching configuration
names) from shlib-versions, leaving shlib-versions entry selection
based purely on sysdeps directories.
An implication of this removal is that the default for any non-Linux
ports using NPTL will be the same SONAMEs for NPTL libraries as for
Linux (as those defaults, previously limited to .*-.*-linux.*, are
left in nptl/shlib-versions and nptl_db/shlib-versions).
Special host_os handling in configure.ac that was purely for
shlib-versions is removed. (The host_os setting is still used for
libc-abis - see
<https://sourceware.org/ml/libc-alpha/2014-01/msg00375.html> regarding
that - but no entries there are affected by this change.)
Tested on x86_64 and x86 that the installed shared libraries are
unchanged by this patch.
* scripts/soversions.awk: Do not handle configuration names.
* Makeconfig ($(common-objpfx)soversions.i): Do not pass cpu,
vendor and os variables to soversions.awk.
* configure.ac: Do not modify gnu-* host_os.
* configure: Regenerated
* shlib-versions: Remove first column with configuration names.
* nptl/shlib-versions: Likewise.
* nptl_db/shlib-versions: Likewise.
* sysdeps/hppa/shlib-versions: Likewise.
* sysdeps/m68k/shlib-versions: Likewise.
* sysdeps/mach/hurd/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/aarch64/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/alpha/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/arm/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/hppa/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/ia64/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/microblaze/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/mips/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/shlib-versions:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/sh/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/tile/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/shlib-versions: Likewise.
libidn/ChangeLog:
* shlib-versions: Remove first column with configuration names.
This patch makes
sysdeps/unix/sysv/linux/powerpc/powerpc64/shlib-versions use %ifdef
conditionals around the different symbol version definitions for big
and little endian. (It doesn't actually change the host patterns used
for those definitions; the point is to make it possible to remove the
first column from shlib-versions by eliminating the last case where it
would be harmful for it to be treated as .*-.*-.*.) The conditional
is based on the ELFv1/ELFv2 distinction rather than BE/LE, since
that's what's already tested in configure and used for the ld.so
soname in the Makefiles. (Of course if BE ELFv2 were supported in
future, it would get new symbol versions and so need new
conditionals.)
* sysdeps/unix/sysv/linux/powerpc/powerpc64/configure.ac
(HAVE_ELFV2_ABI): AC_DEFINE in ELFv2 case.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/configure:
Regenerated.
* config.h.in (HAVE_ELFV2_ABI): New macro undefine.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/shlib-versions:
Condition symbol version definitions on [HAVE_ELFV2_ABI].
This patch eliminates another way in which ex-ports and non-ex-ports
architectures differ, by moving architecture-specific entries from the
top-level shlib-versions file and that in nptl/ to appropriate sysdeps
directories. As with my previous patch
<https://sourceware.org/ml/libc-alpha/2014-06/msg00949.html>, I do not
change the regular expressions used; even where the present
expressions seem more general, I believe they are in fact specific to
the chosen sysdeps directory, because any port that matches the
expression but not the sysdeps directory does not currently exist, and
so would use different symbol versions if added in future (and an
intended goal of these changes is to eliminate the first column in
shlib-versions completely rather than having two different mechanisms
in use for system-specific configuration).
Tested on x86_64 that this does not change the installed shared
libraries. (x86_64 of course does not provide much test coverage for
this patch - what should be architecture-specific contents in
shlib-versions for x86_64 is currently abi-*-ld-soname Makefile
settings, until gnu/lib-names.h is generated more like gnu/stubs.h so
those can move back to shlib-versions.)
* nptl/shlib-versions: Remove architecture-specific entries.
Moved to files in sysdeps.
* shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/shlib-versions: New
file.
* sysdeps/unix/sysv/linux/s390/s390-64/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/sh/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/shlib-versions: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/shlib-versions: Likewise.
This patch continues removing architecture-specific cases from
non-architecture-specific files by moving the logic to use directories
such as /lib64 out of sysdeps/gnu/configure.ac.
A new macro LIBC_SLIBDIR_RTLDDIR is created that sysdeps configure
scripts can use to declare the library directories to be used; the
logic was previously duplicated in configure fragments for aarch64,
mips and x32 as well as in sysdeps/gnu/configure.ac. This macro is
used directly in sysdeps/gnu/configure.ac only to provide the /lib
default (the logic saying that with --prefix=/usr shared libraries go
in /lib not /usr/lib); the architecture cases formerly there are moved
into various new or existing configure.ac files. The new macro is
also used in the various architecture fragments that already had such
logic. In the x32 there was previously a configure fragment, but it
was a directly written one without a .ac file; now a .ac file is used
there instead to generate configure.
Tested x86_64 that the installed shared libraries, and the directory
structure of the installation, are unchanged by this patch.
There is an old bug report - bug 6441 - about library directories
changing after reconfiguring. If this is still applicable - and I
haven't attempted to confirm it or review the old patch pointed to in
that bug - then this patch should reduce the number of places needing
changing in any fix.
* aclocal.m4 (LIBC_SLIBDIR_RTLDDIR): New macro.
* sysdeps/gnu/configure.ac: Use LIBC_SLIBDIR_RTLDDIR. Remove
cases for individual architectures.
* sysdeps/gnu/configure: Regenerated.
* sysdeps/unix/sysv/linux/aarch64/configure.ac: Use
LIBC_SLIBDIR_RTLDDIR.
* sysdeps/unix/sysv/linux/aarch64/configure: Regenerated.
* sysdeps/unix/sysv/linux/mips/configure.ac: Use
LIBC_SLIBDIR_RTLDDIR.
* sysdeps/unix/sysv/linux/mips/configure: Regenerated.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/configure.ac: Use
LIBC_SLIBDIR_RTLDDIR.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/configure:
Regenerated.
* sysdeps/unix/sysv/linux/s390/s390-64/configure.ac: New file.
* sysdeps/unix/sysv/linux/s390/s390-64/configure: New generated
file.
* sysdeps/unix/sysv/linux/sparc/sparc64/configure.ac: New file.
* sysdeps/unix/sysv/linux/sparc/sparc64/configure: New generated
file.
* sysdeps/unix/sysv/linux/x86_64/64/configure.ac: New file.
* sysdeps/unix/sysv/linux/x86_64/64/configure: New generated file.
* sysdeps/unix/sysv/linux/x86_64/x32/configure.ac: New file.
* sysdeps/unix/sysv/linux/x86_64/x32/configure: Generate.
This patch makes the configure adds -D_CALL_ELF=1 when compiler does
not define _CALL_ELF (versions before powerpc64le support). It cleans
up compiler warnings on old compiler where _CALL_ELF is not defined
on powerpc64(be) builds.
It does by add a new config.make variable for configure-deduced
CPPFLAGS and accumulate into that (confix-extra-cppflags). It also
generalizes libc_extra_cflags so it accumulates in sysdeps configure
fragmenets.
To avoid having a ELFv2 binary accidentally picking up an old ABI ld.so,
this patch bumps the soname to ld64.so.2.
In theory (or for testing purposes) this will also allow co-installing
ld.so versions for both ABIs on the same system. Note that the kernel
will already be able to load executables of both ABIs. However, there
is currently no plan to use that theoretical possibility in a any
supported distribution environment ...
Note that in order to check which ABI to use, we need to invoke the
compiler to check the _CALL_ELF macro; this is done in a new configure
check in sysdeps/unix/sysv/linux/powerpc/powerpc64/configure.ac,
replacing the hard-coded value of default-abi in the Makefile.
This updates glibc for the changes in the ELFv2 relating to the
stack frame layout. These are described in more detail here:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01149.htmlhttp://gcc.gnu.org/ml/gcc-patches/2013-11/msg01146.html
Specifically, the "compiler and linker doublewords" were removed,
which has the effect that the save slot for the TOC register is
now at offset 24 rather than 40 to the stack pointer.
In addition, a function may now no longer necessarily assume that
its caller has set up a 64-byte register save area its use.
To address the first change, the patch goes through all assembler
files and replaces immediate offsets in instructions accessing the
ABI-defined stack slots by symbolic offsets. Those already were
defined in ucontext_i.sym and used in some of the context routines,
but that doesn't really seem like the right place for those defines.
The patch instead defines those symbolic offsets in sysdeps.h,
in two variants for the old and new ABI, and uses them systematically
in all assembler files, not just the context routines.
The second change only affected a few assembler files that used
the save area to temporarily store some registers. In those
cases where this happens within a leaf function, this patch
changes the code to store those registers to the "red zone"
below the stack pointer. Otherwise, the functions already allocate
a stack frame, and the patch changes them to add extra space in
these frames as temporary space for the ELFv2 ABI.
This patch adds support for the ELFv2 ABI feature to remove function
descriptors. See this GCC patch for in-depth discussion:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01141.html
This mostly involves two types of changes: updating assembler source
files to the new logic, and updating the dynamic loader.
After the refactoring in the previous patch, most of the assembler source
changes can be handled simply by providing ELFv2 versions of the
macros in sysdep.h. One somewhat non-obvious change is in __GI__setjmp:
this used to "fall through" to the immediately following __setjmp ENTRY
point. This is no longer safe in the ELFv2 since ENTRY defines both
a global and a local entry point, and you cannot simply fall through
to a global entry point as it requires r12 to be set up.
Also, makecontext needs to be updated to set up registers according to
the new ABI for calling into the context's start routine.
The dynamic linker changes mostly consist of removing special code
to handle function descriptors. We also need to support the new PLT
and glink format used by the the ELFv2 linker, see:
https://sourceware.org/ml/binutils/2013-10/msg00376.html
In addition, the dynamic linker now verifies that the dynamic libraries
it loads match its own ABI.
The hack in VDSO_IFUNC_RET to "synthesize" a function descriptor
for vDSO routines is also no longer necessary for ELFv2.
This is the first patch to support the new ELFv2 ABI in glibc.
As preparation, this patch simply refactors some of the powerpc64 assembler
code to move all code related to creating function descriptors (.opd section)
or using function descriptors (function pointer call) into a central place
in sysdep.h.
Note that most locations creating .opd entries were already using macros
in sysdep.h, this patch simply extends this to the remaining places.
No relevant change in generated code expected.
The context established by "makecontext" has a link register pointing
back to an error path within the makecontext routine. This is currently
covered by the CFI FDE for makecontext itself, which is simply wrong
for the stack frame *inside* the context. When trying to unwind (e.g.
doing a backtrace) in a routine inside a context created by makecontext,
this can lead to uninitialized stack slots being accessed, causing the
unwinder to crash in the worst case.
Similarly, during parts of the "setcontext" routine, when the stack
pointer has already been switched to point to the new context, the
address range is still covered by the CFI FDE for setcontext. When
trying to unwind in that situation (e.g. backtrace from an async
signal handler for profiling), it is again possible that the unwinder
crashes.
Theses are all problems in existing code, but the changes in stack
frame layout appear to make the "worst case" much more likely in
the ELFv2 ABI context. This causes regressions e.g. in the libgo
testsuite on ELFv2.
This patch fixes this by ending the makecontext/setcontext FDEs
before those problematic parts of the assembler, similar to what
is already done on other platforms. This fixes the libgo
regression on ELFv2.
http://sourceware.org/ml/libc-alpha/2013-08/msg00092.html
Use conditional form of branch and link to avoid destroying the cpu
link stack used to predict blr return addresses.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S: Use
conditional form of branch and link when obtaining pc.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/makecontext.S: Likewise.
This patch introduces two new convenience functions to set the default
thread attributes used for creating threads. This allows a programmer
to set the default thread attributes just once in a process and then
run pthread_create without additional attributes.
This feature is specifically for the C++ compiler to offload calling
thread_local object destructors on thread program exit, to glibc.
This is to overcome the possible complication of destructors of
thread_local objects getting called after the DSO in which they're
defined is unloaded by the dynamic linker. The DSO is marked as
'unloadable' if it has a constructed thread_local object and marked as
'unloadable' again when all the constructed thread_local objects
defined in it are destroyed.
In order for the __kernel_get_tbfreq vDSO call to work the
INTERNAL_VSYSCALL_NCS macro needed to be updated to prevent it from
assuming an integer return type (since the timebase frequency is a 64-bit
value) by specifying the type of the return type as a macro parameter. The
macro then specifically declares the return value as a 'register' (or
implied pair) of the denoted type. The compiler is then informed that this
register (or implied pair) is to be used for the return value.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_ceil.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_finite.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_floor.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_frexp.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_isinf.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_isnan.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_llround.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_logb.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_lround.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_modf.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_nearbyint.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_remquo.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_rint.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_round.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_scalbln.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_scalbn.c: New file.
* sysdeps/ieee754/ldbl-opt/wordsize-64/s_trunc.c: New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/Implies: Add
ieee754/ldbl-opt/wordsize-64.
* sysdeps/powerpc/powerpc64/Implies: Add
ieee754/dbl-64/wordsize-64.
