[unwinder-portable] [patch 2/3] tests/ Handle missing CFI in .plt

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

Hi Mark,

this patch is for the branch 'portable' to be checked in wotj
'jankratochvil/unwindx86', that is for RHEL-5 systems.
It has been verified it is not needed on RHEL-6.

Jakub Jelinek fixed GNU ld (gold is also fixed now) to provide CFI also for
.plt.  But RHEL-5 still does not have it present.

The testsuite was explicitly testing unwinding for .plt.  Disable it.

I guess these three patches can be checked into the 'portable' branch
together.


Thanks,
Jan

tests/
2013-11-01  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Handle missing CFI in .plt
	(selfdump_callback): Update frame #0 for function raise.
	(prepare_thread): Do not single-step into .plt.

--- a/tests/backtrace.c
+++ b/tests/backtrace.c
@@ -297,8 +297,10 @@ selfdump_callback (pid_t tid, unsigned frameno, Dwarf_Addr pc,
   switch (frameno)
   {
     case 0:
-      /* .plt has no symbols.  */
-      assert (symname == NULL);
+      // RHEL-5 has no .plt CFI.
+      assert (symname != NULL && strcmp (symname, "raise") == 0);
+      // /* .plt has no symbols.  */
+      // assert (symname == NULL);
       break;
     case 1:
       assert (symname != NULL && strcmp (symname, "sigusr2") == 0);
@@ -346,6 +348,7 @@ prepare_thread (pid_t pid2, Dwarf_Addr plt_start, Dwarf_Addr plt_end,
   assert (got == pid2);
   assert (WIFSTOPPED (status));
   assert (WSTOPSIG (status) == SIGUSR1);
+  return; // RHEL-5 has no .plt CFI.
   for (;;)
     {
       errno = 0;