The fix for BZ #17266 (884ddc5081)
removed changes that had gone into cdefs.h to make
__extern_always_inline usable with clang++. This patch adds back
support for clang to detect if GNU inlining semantics are available,
this time without breaking the gcc use case. The check put here is
based on the earlier patch and assertion[1] that checking if
__GNUC_STDC_INLINE__ or __GNUC_GNU_INLINE__ is defined is sufficient
to determine that clang++ suports GNU inlining semantics.
Tested with a simple program that builds with __extern_always_inline
with the patch and fails compilation without it.
#include <stdio.h>
#include <sys/cdefs.h>
extern void foo_alias (void) __asm ("foo");
__extern_always_inline void
foo (void)
{
puts ("hi oh world!");
return foo_alias ();
}
void
foo_alias (void)
{
puts ("hell oh world");
}
int
main ()
{
foo ();
}
[1] https://sourceware.org/ml/libc-alpha/2012-12/msg00306.html
[BZ #17266]
* misc/sys/cdefs.h: Define __extern_always_inline for clang
4.2 and newer.
The check for only __GNUC_STDC_INLINE__ and __GNUC_GNU_INLINE__ may
not be sufficient since those flags were added during initial support
for C99 inlining semantics. There is also a problem with always
defining __extern_inline and __extern_always_inline, since it enables
inline wrapper functions even when GNU inlining semantics are not
guaranteed. This, along with the possibility of such wrappers using
redirection (btowc for example) could result in compiler generating an
infinitely recusrive call to the function.
In fact it was such a recursion that led to this code being written
the way it was; see:
https://bugzilla.redhat.com/show_bug.cgi?id=186410
The initial change was to fix bugs 14530 and 13741, but they can be
resolved by checking if __fortify_function and/or
__extern_always_inline are defined, as it has been done in this patch.
In addition, I have audited uses of __extern_always_inline to make
sure that none of the uses result in compilation errors.
There is however a regression in this patch for llvm, since it reverts
the llvm expectation that __GNUC_STDC_INLINE__ or __GNUC_GNU_INLINE__
definition imply proper extern inline semantics.
2014-09-16 Siddhesh Poyarekar <siddhesh@redhat.com>
Jakub Jelinek <jakub@redhat.com>
[BZ #17266]
* libio/stdio.h: Check definition of __fortify_function
instead of __extern_always_inline to include bits/stdio2.h.
* math/bits/math-finite.h [__USE_XOPEN || __USE_ISOC99]: Also
check if __extern_always_inline is defined.
[__USE_MISC || __USE_XOPEN]: Likewise.
[__USE_ISOC99] Likewise.
* misc/sys/cdefs.h (__fortify_function): Define only if
__extern_always_inline is defined.
[!__cplusplus || __GNUC_PREREQ (4,3)]: Revert to defining
__extern_always_inline and __extern_inline only for g++-4.3
and newer or a compatible gcc.
Summary of changes:
- Use of !_LIBC instead of HAVE_CONFIG_H
- Code changes in [!_LIBC] that don't affect us
- Minor formatting changes
- Use __builtin_expect in shared code
- Define some macros in [_LIBC] that are used in gnulib but never
defined in glibc
- Flip macro check for STRERROR_R_CHAR_P so that it does not throw a
warning
c4c4124473 added the _Noreturn macro for
pre-C11 compilers, but it now throws a new Wundef warning during `make
check` for __STDC_VERSION__ which gcc does not define by default. The
following patch fixes this in line with other uses of __STDC_VERSION__
in the file.
glibc's Makeconfig defines some variables such as $(libm) and $(libdl)
for linking with libraries built by glibc, and nptl/Makeconfig
(included by the toplevel Makeconfig) defines others such as
$(shared-thread-library).
In some places glibc's Makefiles use those variables when linking
against the relevant libraries, but in other places they hardcode the
location of the libraries in the build tree. This patch cleans up
various places to use the variables that already exist (in the case of
libm, replacing several duplicate definitions of a $(link-libm)
variable in subdirectory Makefiles). (It's not necessarily exactly
equivalent to what the existing code does - in particular,
$(shared-thread-library) includes libpthread_nonshared, but is
replacing places that just referred to libpthread.so. But I think
that change is desirable on the general principle of linking things as
close as possible to the way in which they would be linked with an
installed library, unless there is a clear reason not to do so.)
To support running tests with an installed copy of glibc without
needing the full build tree from when that copy was built, I think it
will be useful to use such variables more generally and systematically
- every time the rules for building a test refer to some file from the
build tree that's also installed by glibc, use a makefile variable so
that the installed-testing case can point those variables to installed
copies of the files. This patch just deals with straightforward cases
where such variables already exist.
It's quite possible some uses of $(shared-thread-library) should
actually be a new $(thread-library) variable that's set appropriately
in the --disable-shared case, if those uses would in fact work without
shared libraries. I didn't change the status quo that those cases
hardcode use of a shared library whether or not it's actually needed
(but other uses such as $(libm) and $(libdl) would now get the static
library if the shared library isn't built, when some previously
hardcoded use of the shared library - if they actually need shared
libraries, the test itself needs an enable-shared conditional anyway).
Tested x86_64.
* benchtests/Makefile
($(addprefix $(objpfx)bench-,$(bench-math))): Depend on $(libm),
not $(common-objpfx)math/libm.so.
($(addprefix $(objpfx)bench-,$(bench-pthread))): Depend on
$(shared-thread-library), not $(common-objpfx)nptl/libpthread.so.
* elf/Makefile ($(objpfx)noload): Depend on $(libdl), not
$(common-objpfx)dlfcn/libdl.so.
($(objpfx)tst-audit8): Depend on $(libm), not
$(common-objpfx)math/libm.so.
* malloc/Makefile ($(objpfx)libmemusage.so): Depend on $(libdl),
not $(common-objpfx)dlfcn/libdl.so.
* math/Makefile
($(addprefix $(objpfx),$(filter-out $(tests-static),$(tests)))):
Depend on $(libm), not $(objpfx)libm.so. Do not condition on
[$(build-shared) = yes].
($(objpfx)test-fenv-tls): Depend on $(shared-thread-library), not
$(common-objpfx)nptl/libpthread.so.
* misc/Makefile ($(objpfx)tst-tsearch): Depend on $(libm), not
$(common-objpfx)math/libm.so$(libm.so-version) or
$(common-objpfx)math/libm.a depending on [$(build-shared) = yes].
* nptl/Makefile ($(objpfx)tst-unload): Depend on $(libdl), not
$(common-objpfx)dlfcn/libdl.so.
* setjmp/Makefile (link-libm): Remove variable.
($(objpfx)tst-setjmp-fp): Depend on $(libm), not $(link-libm).
* stdio-common/Makefile (link-libm): Remove variable.
($(objpfx)tst-printf-round): Depend on $(libm), not $(link-libm).
* stdlib/Makefile (link-libm): Remove variable.
($(objpfx)bug-getcontext): Depend on $(libm), not $(link-libm).
($(objpfx)tst-strtod-round): Likewise.
($(objpfx)tst-tininess): Likewise.
($(objpfx)tst-strtod-underflow): Likewise.
($(objpfx)tst-strtod6): Likewise.
($(objpfx)tst-tls-atexit): Depend on $(shared-thread-library) and
$(libdl), not $(common-objpfx)nptl/libpthread.so and
$(common-objpfx)dlfcn/libdl.so.
This patch systematically renames miscellaneous tests so their outputs
use a *.out name (unless the test is just running some glibc program
with its conventional output file name, rather than a special program
at all, as in catgets tests generating *.cat). In the case of the
iconv test test-iconvconfig, output is redirected where it wasn't
before.
In various places the "generated" variable is updated to reflect the
revised test names; in iconvdata/Makefile a typo (mmtrace-tst-loading)
is also fixed. resolv/Makefile sets both "generate" (which appears
unused) and "generated". Bitrot in the settings of these variables
could no doubt be fixed so that "make clean" after build and testing
leaves results the same as after configure (and indeed the
tests-special / xtests-special variables could be used to simplify
things, by removing those files automatically rather than listing them
manually in these variables), and "make distclean" leaves an empty
build directory, but right now it appears various files don't get
deleted. I think they are liable to continue to bitrot in the absence
of routine testing that these targets actually work, given that
building in the source directory isn't supported and that was the main
use of such makefile targets.
Tested x86_64.
* elf/Makefile (tests-special): Rename tests to end with .out.
($(objpfx)noload-mem): Likewise.
($(objpfx)tst-leaks1-mem): Likewise.
($(objpfx)tst-leaks1-static-mem.out): Likewise.
* iconv/Makefile (xtests-special): Change test-iconvconfig to
$(objpfx)test-iconvconfig.out.
(test-iconvconfig): Change to $(objpfx)test-iconvconfig.out. Use
set -e inside subshell and redirect output to file.
* iconvdata/Makefile (generated): Rename tests to end with .out.
Correct type.
(tests-special): Rename tests to end with .out.
($(objpfx)mtrace-tst-loading): Likewise.
* intl/Makefile (generated): Likewise.
(tests-special): Likewise.
($(objpfx)mtrace-tst-gettext): Likewise.
* misc/Makefile (generated): Likewise.
(tests-special): Likewise.
($(objpfx)tst-error1-mem): Likewise.
* nptl/Makefile (tests-special): Likewise.
($(objpfx)tst-stack3-mem): Likewise.
(generated): Likewise.
* posix/Makefile (generated): Likewise.
(tests-special): Likewise.
(xtests-special): Likewise.
($(objpfx)tst-fnmatch-mem): Likewise.
($(objpfx)bug-regex2-mem): Likewise.
($(objpfx)bug-regex14-mem): Likewise.
($(objpfx)bug-regex21-mem): Likewise.
($(objpfx)bug-regex31-mem): Likewise.
($(objpfx)tst-vfork3-mem): Likewise.
($(objpfx)tst-rxspencer-no-utf8-mem): Likewise.
($(objpfx)tst-pcre-mem): Likewise.
($(objpfx)tst-boost-mem): Likewise.
($(objpfx)bug-ga2-mem): Likewise.
($(objpfx)bug-glob2-mem): Likewise.
* resolv/Makefile (generate): Likewise.
(tests-special): Likewise.
(xtests-special): Likewise.
(generated): Likewise.
($(objpfx)mtrace-tst-leaks): Likewise.
($(objpfx)mtrace-tst-leaks2): Likewise.
localedata:
* Makefile (generated): Rename tests to end with .out.
(tests-special): Likewise.
($(objpfx)mtrace-tst-leaks): Likewise.
This patch is a revised and updated version of
<https://sourceware.org/ml/libc-alpha/2014-01/msg00196.html>.
In order to generate overall summaries of the results of all tests in
the glibc testsuite, we need to identify and concatenate the files
with the results of individual tests.
Tomas Dohnalek's patch used $(common-objpfx)*/*.test-result for this.
However, the normal glibc approach is explicit enumeration of the
expected set of files with a given property, rather than all files
matching some pattern like that. Furthermore, we would like to be
able to mark tests as UNRESOLVED if the file with their results is for
some reason missing, and in future we would like to be able to mark
tests as UNSUPPORTED if they are disabled for a particular
configuration (rather than simply having them missing from the list of
tests as at present). Such handling of tests that were not run or did
not record results requires an explicit enumeration of tests.
For the tests following the default makefile rules, $(tests) (and
$(xtests)) provides such an enumeration. Others, however, are added
directly as dependencies of the "tests" and "xtests" makefile
targets. This patch changes the makefiles to put them in variables
tests-special and xtests-special, with appropriate dependencies on the
tests listed there then being added centrally.
Those variables are used in Rules and so need to be set before Rules
is included in a subdirectory makefile, which is often earlier in the
makefile than the dependencies were present before. We previously
discussed the question of where to include Rules; see the question at
<https://sourceware.org/ml/libc-alpha/2012-11/msg00798.html>, and a
discussion in
<https://sourceware.org/ml/libc-alpha/2013-01/msg00337.html> of why
Rules is included early rather than late in subdirectory makefiles.
It was necessary to avoid an indirection through the check-abi target
and get the check-abi-* targets for individual libraries into the
tests-special variable. The intl/ test $(objpfx)tst-gettext.out,
previously built only because of dependencies from other tests, was
also added to tests-special for the same reason.
The entries in tests-special are the full makefile targets, complete
with $(objpfx) and .out. If a future change causes tests to be named
consistently with a .out suffix, this can be changed to include just
the path relative to $(objpfx), without .out.
Tested x86_64, including that the same set of files is generated in
the build directory by a build and testsuite run both before and after
the patch (except for changes to the
elf/tst-null-argv.debug.out.<number> file name), and a build with
run-built-tests=no to verify there aren't any more obvious instances
of the issue Marcus Shawcroft reported with a previous version in
<https://sourceware.org/ml/libc-alpha/2014-01/msg00462.html>.
* Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(tests): Depend on $(tests-special).
* Makerules (check-abi-list): New variable.
(check-abi): Depend on $(check-abi-list).
[$(subdir) = elf] (tests-special): Add
$(objpfx)check-abi-libc.out.
[$(build-shared) = yes && subdir] (tests-special): Add
$(check-abi-list).
[$(build-shared) = yes && subdir] (tests): Do not depend on
check-abi.
* Rules (tests): Depend on $(tests-special).
(xtests): Depend on $(xtests-special).
* catgets/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* conform/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* elf/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* grp/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* iconv/Makefile (xtests): Change dependencies to ....
(xtests-special): ... additions to this variable.
* iconvdata/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* intl/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable. Also add
$(objpfx)tst-gettext.out.
* io/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* libio/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* malloc/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* misc/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* nptl/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* nptl_db/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* posix/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(xtests): Change dependencies to ....
(xtests-special): ... additions to this variable.
* resolv/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(xtests): Change dependencies to ....
(xtests-special): ... additions to this variable.
* stdio-common/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
(do-tst-unbputc): Remove target.
(do-tst-printf): Likewise.
* stdlib/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* string/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
* sysdeps/x86/Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
localedata:
* Makefile (tests): Change dependencies to ....
(tests-special): ... additions to this variable.
In <https://sourceware.org/ml/libc-alpha/2014-01/msg00196.html> I
noted it was necessary to add includes of Makeconfig early in various
subdirectory makefiles for the tests-special variable settings added
by that patch to be conditional on configuration information. No-one
commented on the general question there of whether Makeconfig should
always be included immediately after the definition of subdir.
This patch implements that early inclusion of Makeconfig in each
directory (which is a lot easier than consistent placement of includes
of Rules). Includes are added if needed, or moved up if already
present. Subdirectory "all:" targets are removed, since Makeconfig
provides one.
There is potential for further cleanups I haven't done. Rules and
Makerules have code such as
ifneq "$(findstring env,$(origin headers))" ""
headers :=
endif
to override to empty any value of various variables that came from the
environment. I think there is a case for Makeconfig setting all the
subdirectory variables (other than subdir) to empty to ensure no
outside value is going to take effect if a subdirectory fails to
define a variable. (A list of such variables, possibly out of date
and incomplete, is in manual/maint.texi.) Rules and Makerules would
give errors if Makeconfig hadn't already been included, instead of
including it themselves. The special code to override values coming
from the environment would then be obsolete and could be removed.
Tested x86_64, including that installed binaries are identical before
and after the patch.
* argp/Makefile: Include Makeconfig immediately after defining
subdir.
* assert/Makefile: Likewise.
* benchtests/Makefile: Likewise.
* catgets/Makefile: Likewise.
* conform/Makefile: Likewise.
* crypt/Makefile: Likewise.
* csu/Makefile: Likewise.
(all): Remove target.
* ctype/Makefile: Include Makeconfig immediately after defining
subdir.
* debug/Makefile: Likewise.
* dirent/Makefile: Likewise.
* dlfcn/Makefile: Likewise.
* gmon/Makefile: Likewise.
* gnulib/Makefile: Likewise.
* grp/Makefile: Likewise.
* gshadow/Makefile: Likewise.
* hesiod/Makefile: Likewise.
* hurd/Makefile: Likewise.
(all): Remove target.
* iconvdata/Makefile: Include Makeconfig immediately after
defining subdir.
* inet/Makefile: Likewise.
* intl/Makefile: Likewise.
* io/Makefile: Likewise.
* libio/Makefile: Likewise.
(all): Remove target.
* locale/Makefile: Include Makeconfig immediately after defining
subdir.
* login/Makefile: Likewise.
* mach/Makefile: Likewise.
(all): Remove target.
* malloc/Makefile: Include Makeconfig immediately after defining
subdir.
(all): Remove target.
* manual/Makefile: Include Makeconfig immediately after defining
subdir.
* math/Makefile: Likewise.
* misc/Makefile: Likewise.
* nis/Makefile: Likewise.
* nss/Makefile: Likewise.
* po/Makefile: Likewise.
(all): Remove target.
* posix/Makefile: Include Makeconfig immediately after defining
subdir.
* pwd/Makefile: Likewise.
* resolv/Makefile: Likewise.
* resource/Makefile: Likewise.
* rt/Makefile: Likewise.
* setjmp/Makefile: Likewise.
* shadow/Makefile: Likewise.
* signal/Makefile: Likewise.
* socket/Makefile: Likewise.
* soft-fp/Makefile: Likewise.
* stdio-common/Makefile: Likewise.
* stdlib/Makefile: Likewise.
* streams/Makefile: Likewise.
* string/Makefile: Likewise.
* sunrpc/Makefile: Likewise.
(all): Remove target.
* sysvipc/Makefile: Include Makeconfig immediately after defining
subdir.
* termios/Makefile: Likewise.
* time/Makefile: Likewise.
* timezone/Makefile: Likewise.
(all): Remove target.
* wcsmbs/Makefile: Include Makeconfig immediately after defining
subdir.
* wctype/Makefile: Likewise.
libidn/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
localedata/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
(all): Remove target.
nptl/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
nptl_db/ChangeLog:
* Makefile: Include Makeconfig immediately after defining subdir.
Shifting into the sign position is currently supported as a GCC
extension, but explicitly subjected to future changes. Computation
in the unsigned type followed by a cast to the signed type is a GCC
extension that will be available forever.
[BZ 15846] As discussed in the recent thread on my $EXEC_ORIGIN patch
and in BZ 15846, getauxval() presently has no unambiguous way of
reporting an error condition. It currently returns zero on error, but
this may also be a valid result for some auxv entries. As there is no
clear invalid result for all current and future auxv entries, this patch
sets errno (following a suggestion in the BZ entry).
This version of the patch also adds documentation and tests for the
value-not-found conditions in getauxval().
Use the __gnu_inline__ attribute in _FORTIFY_SOURCE's __extern_always_inline
macro whenever the compiler supports it. Previously this macro only included
the __gnu_inline__ attribute in C++ mode for gcc >= 4.3. However,
__gnu_inline__ semantics are always desired for the __extern_always_inline
functions, and are available in g++ 4.2 (and some releases of g++ 4.1, and
also in Clang, which claims to be g++ 4.2).
This change stops g++-4.2 from emitting weak definitions for the fortify
wrapper functions if they can't be inlined, and also improves Clang
compatibility.
Since we want to use this in installed headers, move it to the installed
sys/cdefs.h. This requires a slight tweaking of the name (add trailing
underscores).
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
