[PATCH 4/4] libgcc: Use _dl_find_eh_frame in _Unwind_Find_FDE

[Jakub Jelinek]

On Thu, Nov 25, 2021 at 09:42:53PM +0100, Florian Weimer wrote:
> I've included a simplified version below, based on the _dl_find_object
> patch for glibc.
> 
> This is a bit difficult to test, but I ran a full toolchain bootstrap
> with GCC + glibc on all glibc-supported architectures (except Hurd and
> one m68k variant; they do not presnetly build, see Joseph's testers).
> 
> I also tested this by copying the respective GCC-built libgcc_s into a
> glibc build tree for run-time testing on i686-linux-gnu and
> x86_64-linux-gnu.  There weren't any issues.  There are a buch of
> unwinder tests in glibc, giving at least some coverage.

See the comment I've just sent on this patch.
If the DLFO_STRUCT_HAS_EH_DBASE and DLFO_STRUCT_HAS_EH_COUNT
macros are gone, we'd need to use __GLIBC_PREREQ or configure test
or combination of the two.

Otherwise LGTM.

> Subject: libgcc: Use _dl_find_object in _Unwind_Find_FDE
> 
> libgcc/ChangeLog:
> 
> 	* unwind-dw2-fde-dip.c (_Unwind_Find_FDE): Call _dl_find_object
> 	if available.

	Jakub