From 2fe42e82135c2d1cea50ee7126283fa5cc723d52 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Thu, 25 Jul 2013 14:34:50 +0000 Subject: remove pop_target This patch fixes the target double-close problem (PR remote/15266), and in the process removes pop_target entire (PR remote/15256). The first issue is that pop_target calls target_close. However, it then calls unpush_target, which also calls target_close. This means targets must be able to be closed twice. Not only is this strange, but it also directly contradicts the contract of to_xclose targets. (We currently have just a single such target, and it is never pushed; but I plan to add more, and so this latent bug is triggered.) The second issue is that it seems to me that calling pop_target is often unsafe. This is what cropped up in 15256, where the remote target assumed that it could pop_target -- but there was another target higher on the stack, leading to confusion. But, it is always just as easy to call unpush_target as it is to call pop_target; and it is also safer. So, removing pop_target seemed like an improvement. Finally, this adds an assertion to target_close to ensure that no currently-pushed target can be closed. Built and regtested on x86-64 Fedora 18; both natively and using the native-gdbserver board file. PR remote/15256, PR remote/15266: * bfd-target.c (target_bfd_reopen): Initialize to_magic. * monitor.c (monitor_detach): Use unpush_target. * remote-m32r-sdi.c (m32r_detach): Use unpush_target. * remote-mips.c (mips_detach): Use unpush_target. Don't call mips_close. * remote-sim.c (gdbsim_detach): Use unpush_target. * target.c (pop_target): Remove. (pop_all_targets_above): Don't call target_close. (target_close): Assert that the target is unpushed. * target.h (pop_target): Don't declare. * tracepoint.c (tfile_open): Use unpush_target. --- gdb/target.c | 17 ++--------------- 1 file changed, 2 insertions(+), 15 deletions(-) (limited to 'gdb/target.c') diff --git a/gdb/target.c b/gdb/target.c index 37b0a94b0cf..e3dcb47f514 100644 --- a/gdb/target.c +++ b/gdb/target.c @@ -1093,26 +1093,11 @@ unpush_target (struct target_ops *t) return 1; } -void -pop_target (void) -{ - target_close (target_stack); /* Let it clean up. */ - if (unpush_target (target_stack) == 1) - return; - - fprintf_unfiltered (gdb_stderr, - "pop_target couldn't find target %s\n", - current_target.to_shortname); - internal_error (__FILE__, __LINE__, - _("failed internal consistency check")); -} - void pop_all_targets_above (enum strata above_stratum) { while ((int) (current_target.to_stratum) > (int) above_stratum) { - target_close (target_stack); if (!unpush_target (target_stack)) { fprintf_unfiltered (gdb_stderr, @@ -3781,6 +3766,8 @@ debug_to_open (char *args, int from_tty) void target_close (struct target_ops *targ) { + gdb_assert (!target_is_pushed (targ)); + if (targ->to_xclose != NULL) targ->to_xclose (targ); else if (targ->to_close != NULL) -- cgit v1.2.1