From cf3fbed4a00e668ffcad1b878eccec87334fdcff Mon Sep 17 00:00:00 2001 From: Joel Brobecker Date: Tue, 21 Nov 2017 14:03:06 -0800 Subject: problem debugging ravenscar programs if runtime is stripped Trying to debug a program using a stripped version of the ravenscar runtime, we can get the following error: (gdb) cont Continuing. Cannot find Ada_Task_Control_Block type. Aborting This is because the ravenscar-thread layer makes the assumption that the runtime is built the way we expect it, meaning that the Ada tasking units we rely on for Ada tasking debugging, are built with debugging information, and that this debug information has not been stripped from the runtime. When this assumption is not true, resuming such a program can trigger the error above, which then leads GDB a little confused. For instance, we can see things like: (gdb) bt Target is executing. This patch fixes the issue by disabling the ravenscar thread layer if we detect that the runtime is missing some of the debugging info we need in order to support Ada task debugging. This is the best we can do, as the ravenscar-thread layer actually depends on the ada-tasks layer to implement thread debugging. gdb/ChangeLog: * ada-lang.h (ada_get_tcb_types_info): Add declaration. * ada-tasks.c (ada_get_tcb_types_info): Renames get_tcb_types_info. Make non-static. Change return type to char *. Adjust code accordingly. Rewrite the function's documentation. (read_atcb): Adjust call to get_tcb_types_info accordingly. * ravenscar-thread.c (ravenscar_inferior_created): Check that we have enough debugging information in the runtime to support Ada task debugging before we enable the ravenscar-thread layer. --- gdb/ravenscar-thread.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'gdb/ravenscar-thread.c') diff --git a/gdb/ravenscar-thread.c b/gdb/ravenscar-thread.c index 83dfd9d..e792227 100644 --- a/gdb/ravenscar-thread.c +++ b/gdb/ravenscar-thread.c @@ -519,12 +519,20 @@ ravenscar_core_of_thread (struct target_ops *ops, ptid_t ptid) static void ravenscar_inferior_created (struct target_ops *target, int from_tty) { + const char *err_msg; if (!ravenscar_task_support || gdbarch_ravenscar_ops (target_gdbarch ()) == NULL || !has_ravenscar_runtime ()) return; + err_msg = ada_get_tcb_types_info (); + if (err_msg != NULL) + { + warning (_("%s. Task/thread support disabled.\n"), err_msg); + return; + } + ravenscar_update_inferior_ptid (); push_target (&ravenscar_ops); } -- cgit v1.1