We need NO_RTLD_HIDDEN because of the need for PLT calls in ld.so.
See Roland's comment in
https://sourceware.org/bugzilla/show_bug.cgi?id=15605
"in the Hurd it's crucial that calls like __mmap be the libc ones
instead of the rtld-local ones after the bootstrap phase, when the
dynamic linker is being used for dlopen and the like."
We used to just avoid all hidden use in the rtld ; this commit switches to
keeping only those that should use PLT calls, i.e. essentially those defined in
sysdeps/mach/hurd/dl-sysdep.c:
__assert_fail
__assert_perror_fail
__*stat64
_exit
This fixes a few startup issues, notably the call to __tunable_get_val that is
made before PLTs are set up.
and add _nocancel variants.
* sysdeps/mach/hurd/write.c (__libc_write): Call __write_nocancel
surrounded by enabling async cancel, to replace implementation moved
to...
* sysdeps/mach/hurd/write_nocancel.c (__write_nocancel): ... here.
* sysdeps/mach/hurd/pwrite64.c (__libc_pwrite64): Call
__pwrite64_nocancel surrounded by enabling async cancel, to replace
implementation moved to...
* sysdeps/mach/hurd/pwrite64_nocancel.c (__pwrite64_nocancel): ... here.
* sysdeps/mach/hurd/Makefile (sysdep_routines): Add write_nocancel and
pwrite64_nocancel.
* sysdeps/mach/hurd/not-cancel.h (__write_nocancel,
__pwrite64_nocancel): Replace macros with prototypes with a hidden proto on
libc.
* sysdeps/mach/hurd/dl-sysdep.c (__write_nocancel): New alias, check
that it is not hidden.
* sysdeps/mach/hurd/Versions (libc.GLIBC_PRIVATE): Add __write_nocancel.
(ld.GLIBC_PRIVATE): Add __write_nocancel.
* sysdeps/mach/hurd/i386/localplt.data (__write_nocancel): Add
reference.
and add _nocancel variants.
* sysdeps/mach/hurd/pread64.c (__libc_pread64): Call __pread64_nocancel
surrounded by enabling async cancel, to replace implementation moved to...
* sysdeps/mach/hurd/pread64_nocancel.c (__pread64_nocancel): ... here.
* sysdeps/mach/hurd/read.c (__libc_read): Call __read_nocancel surrounded by
enabling async cancel, to replace implementation moved to...
* sysdeps/mach/hurd/read_nocancel.c (__read_nocancel): ... here.
* sysdeps/mach/hurd/Makefile (sysdep_routines): Add read_nocancel and
pread64_nocancel.
* sysdeps/mach/hurd/not-cancel.h (__read_nocancel, __pread64_nocancel):
Replace macros with prototypes with a hidden proto on libc.
* sysdeps/mach/hurd/dl-sysdep.c: Include <not-cancel.h>.
(__pread64_nocancel): New alias, check that it is not hidden.
(__read_nocancel): New alias, check that it is not hidden.
* sysdeps/mach/hurd/Versions (libc.GLIBC_PRIVATE): Add __read_nocancel and
__pread64_nocancel.
(ld.GLIBC_2.1): Add __pread64.
(ld.GLIBC_PRIVATE): Add __read_nocancel and __pread64_nocancel.
* sysdeps/mach/hurd/i386/ld.abilist (__pread64): Add symbol.
* sysdeps/mach/hurd/i386/localplt.data (__read_nocancel, __pread64,
__pread64_nocancel): Add references.
This change makes it easier to set a breakpoint on these calls.
This also addresses the issue that including <ldsodefs.h> without
<unistd.h> does not result usable _dl_*printf macros because of the
use of the STD*_FILENO macros there.
(The private symbol for _dl_fatal_printf will go away again
once the exception handling implementation is unified between
libc and ld.so.)
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Exporting functions and relying on symbol interposition from libc.so
makes the choice of implementation dependent on DT_NEEDED order, which
is not what some compiler drivers expect.
This commit replaces one magic mechanism (symbol interposition) with
another one (preprocessor-/compiler-based redirection). This makes
the hand-over from the minimal malloc to the full malloc more
explicit.
Removing the ABI symbols is backwards-compatible because libc.so is
always in scope, and the dynamic loader will find the malloc-related
symbols there since commit f0b2132b35
("ld.so: Support moving versioned symbols between sonames
[BZ #24741]").
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
After commit f7649d5780 ("dlopen: Do not
block signals"), the dynamic linker no longer uses sigprocmask, which
means that it does not have to be made available explicitly on hurd.
This reverts commit 892badc9bb
("hurd: Make __sigprocmask GLIBC_PRIVATE") and commit
d5ed9ba29a ("hurd: Fix ld.so link"),
but keeps the comment changes from the second commit.
ld.so symbols to be overriden by libc need to be extern to really get
overriden. __access happens to have never been exposed, putting it to
GLIBC_PRIVATE.
ld.so symbols to be overriden by libc need to be extern to really get
overriden. __getcwd happens to have never been exposed, putting it to
GLIBC_PRIVATE.
ld.so symbols to be overriden by libc need to be extern to really get
overriden.
* sysdeps/mach/hurd/not-errno.h: New file.
* sysdeps/mach/hurd/i386/localplt.data: Update accordingly.
ld.so symbols to be overriden by libc need to be extern to really get
overriden.
* sysdeps/mach/hurd/dl-unistd.h (__access, __brk, __lseek, __read,
__sbrk): Do not set attribute_hidden.
* sysdeps/mach/hurd/i386/ld.abilist: Update accordingly.
* sysdeps/mach/hurd/i386/localplt.data: Update accordingly.
ld.so symbols to be overriden by libc need to be extern to really get
overriden.
More fixes are needed to avoid the hidden attribute.
* sysdeps/mach/hurd/Versions (libc): Make __access and
__access_noerrno external so they can override the ld symbols.
(ld): Make __access, __read, __sbrk, __strtoul_internal, __write,
__writev, __open64, __access_noerrno extern so they can be overrided.
* sysdeps/mach/hurd/i386/libc.abilist: Update accordingly.
* sysdeps/mach/hurd/i386/ld.abilist: Update accordingly.
