Given my patch
<https://gcc.gnu.org/ml/gcc-patches/2017-08/msg00965.html> for the
ICEs building a glibc string function test for SH, the testsuite can
build completely for SH with GCC 7 and mainline. However, there is a
test failure that does not appear for GCC 6: check-localplt fails
because of an abort PLT reference in libc.so.
Given the lack of a trap insn pattern for SH, it seems unavoidable
that the compiler might sometimes generate abort calls, and such abort
calls (generated from __builtin_trap when there is no trap insn
pattern) will be unaffected by the normal mapping to __GI_abort for
calls within glibc. Thus, this patch allows (but does not require) an
abort PLT reference in libc.so for SH.
Tested for sh4-linux-gnu with build-many-glibcs.py (GCC 7, with my
patch applied).
* sysdeps/unix/sysv/linux/sh/localplt.data: Allow abort in
libc.so.
This commit separates allocating and raising exceptions. This
simplifies catching and re-raising them because it is no longer
necessary to make a temporary, on-stack copy of the exception message.
It is no longer needed since commit 6c444ad6e9
(elf: Do not use memalign for TCB/TLS blocks allocation [BZ #17730]).
Applications do not link against ld.so and will use the definition in
libc.so, so there is no ABI impact.
This change moves the main implementation of _dl_catch_error,
_dl_signal_error to libc.so, where TLS variables can be used
directly. This removes a writable function pointer from the
rtld_global variable.
For use during initial relocation, minimal implementations of these
functions are provided in ld.so. These are eventually interposed
by the libc.so implementations. This is implemented by compiling
elf/dl-error-skeleton.c twice, via elf/dl-error.c and
elf/dl-error-minimal.c.
As a side effect of this change, the static version of dl-error.c
no longer includes support for the
_dl_signal_cerror/_dl_receive_error mechanism because it is only
used in ld.so.
This patch adds a localplt.data file for sh so that test passes. The
architecture-specific entries are for _Unwind_Find_FDE, _exit and
__errno_location.
Tested for sh3 and sh4.
* sysdeps/unix/sysv/linux/sh/localplt.data: New file.