[PATCH] configure: Add --disable-libsupport option

[Joseph Myers]

On Tue, 25 Mar 2025, Florian Weimer wrote:

> This option allows to build (but not test) glibc with a GCC that
> was built with --enable-shared, but which does not have access
> to its libgcc_s.so.1 DSO.  In this scenario, the -lgcc_s test
> added in commit 5dfbc3c43ecc1bcfc760a032c91bb002660051bc ("support:
> Link links-dso-program-c with libgcc_s only if available") fails
> and linking against -lgcc_s is skipped.  However, the test program
> still has a dependency on _Unwind_Resume, but for a GCC built
> with --enable-shared, this symbol is not available with -lgcc.

Does linking with -lgcc_eh work in the case where libgcc_s does not work?  
(See the long "How to link against libgcc." comment in Makeconfig; even if 
none of the makefile variables there works for this particular test 
program, I'd hope the strategy of linking with -lgcc_eh would work.  And 
if it does work, it seems preferable to having a special-case configure 
option for this.)

-- 
Joseph S. Myers
josmyers@redhat.com