[Bug testsuite/65126] [5 Regresion] additional_sources not defined anymore during dg-final

["mkuvyrkov at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65126

Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |mkuvyrkov at gcc dot gnu.org

--- Comment #5 from Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> ---
The problem here is that gcc_target_compile (and, probably, other
*_target_compile procs) clears out additional_sources as soon as it is done.

I don't immediately know how to fix this properly.  A quick fix may be to delay
clearing out additional_sources till a later point.

More generally, from what I see GCC's testsuite doesn't have coordinated
maintenance of its global state (additional_* and other variables, see
gcc-dg.exp).  It would be a nice cleanup to have PUSH and POP operations for
global state that could used to 

1. clearing of state for next test
  -- the POP to a reference clean state would be done once all parts of the
test would finish, thus removing the need to clear out additional_sources after
compilation (== midway through running the test).

2. saving / restoring of state for target-supports checks.