g++ testing problem (check_cxa_atexit_available)

[Steve Ellcey <sje at cup dot hp dot com>]

It looks like I broke check_cxa_atexit_available when I brought it over
from the libstdc++ test subdirectory to gcc.  Four libstdc++ tests that
should be passing on linux are showing up as XPASS tests because
dg-require-cxa-atexit is returning false on systems that do have a
proper __cxa_atexit function.

I think this is because the test program that check_cxa_atexit_available
runs is failing because LD_LIBRARY_PATH is not set when the program is
run.  But I am not sure how it used to get set in the libstdc++ test
environment and why it is not getting set now that I moved it to the gcc
subdir.

I tried modifying check_cxa_atexit_available to use g++_target_compile
and g++_load instead of ${tool}_target_compile and ${tool}_load, but
that didn't help and I tried adding a call to set_ld_library_path_env_vars
right before the "set result [g++_load "./$exe" "" ""]" line in
check_cxa_atexit_available, but that didn't help either.

Does anyone have any idea on how to fix this?  I couldn't find where
g++_load was defined.  I see g++_target_compile in g++.dg but the
compile isn't the problem, it is the execution of the resulting
program where I think things go wrong.

Steve Ellcey
sje@cup.hp.com