% gdb -q ''
... or ...
% gdb -q
(gdb) file ''
... both cause GDB to crash with an invalid free. This is because
exec_file_attach is attempting to free a string that has not been
allocated. The string is only allocated if openp is successful.
But in the case of this obviously invalid filename, openp fails,
and leaves scratch_pathname uninitialized, thus causing the xfree
to fail.
The fix is to enable the associated cleanup after we have verified
that openp was successful.
gdb/ChangeLog (By Keith Seitz <keiths@redhat.com>):
* exec.c (exec_file_attach): Move cleanup after verifying that
memory has in fact been allocated.
gdb/testsuite/ChangeLog:
* gdb.base/empty_exe.exp: New testcase.
17d6efc44b