RFC: missing do_cleanups call in dwarf2_frame_cache

[Tom Tromey <tromey@redhat.com>]

While debugging a different problem, I found a spot in
dwarf2_frame_cache that fails to call do_cleanups before returning.  The
usual rule is that ordinary functions should not leave any dangling
cleanups.

Built and regtested on x86-64 Fedora 16.

Tom

	* dwarf2-frame.c (dwarf2_frame_cache): Call do_cleanups before
	return.
---
 gdb/dwarf2-frame.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/gdb/dwarf2-frame.c b/gdb/dwarf2-frame.c
index 01786ef..741a103 100644
--- a/gdb/dwarf2-frame.c
+++ b/gdb/dwarf2-frame.c
@@ -1110,6 +1110,7 @@ dwarf2_frame_cache (struct frame_info *this_frame, void **this_cache)
       if (ex.error == NOT_AVAILABLE_ERROR)
 	{
 	  cache->unavailable_retaddr = 1;
+	  do_cleanups (old_chain);
 	  return cache;
 	}
 
-- 
1.7.7.6