Hi Corinna,
On 8/28/2014 9:57 AM, Corinna Vinschen wrote:
On Aug 13 16:57, Corinna Vinschen wrote:
On Aug 13 10:28, Ken Brown wrote:
I'm getting errors with the latest gdb when trying to debug programs that
depend on glib. Here's an example, run from an xterm window:
$ gdb /usr/bin/gvim
GNU gdb (GDB) 7.8
[...]
Reading symbols from /usr/bin/gvim...(no debugging symbols found)...done.
(gdb) r
Starting program: /usr/bin/gvim
[New Thread 4860.0x1b44]
Traceback (most recent call last):
File "/usr/share/gdb/auto-load/usr/bin/cyggobject-2.0-0.dll-gdb.py", line
9, in <module>
from gobject import register
File "/usr/share/glib-2.0/gdb/gobject.py", line 3, in <module>
import gdb.backtrace
ImportError: No module named backtrace
I see this error, too. Unfortunately I'm not a python guru so this
is rather opaque to me. gdb itself doesn't provide a gdb.backtrace
method, afaics.
However, despite this message, gvim starts normally. And emacs-nox as
well as many other CLI applications can be started just fine, too.
But GDB hangs with emacs-X11 for some reason, even if I disable the
python modules. From a quick GDB session it's not clear why this occurs :(
I reported the problem upstream in a bugzilla entry already handling
strange GDB hangs:
https://sourceware.org/bugzilla/show_bug.cgi?id=17247
That bug appears to be something different. But I managed to fix the
problem without actually understanding the code. I looked at cgf's
patches from his build of gdb-7.6.50-4, and I noticed that some of his
changes didn't make it into your gdb-7.8-1.src.patch. The missing ones
are collected in the attached "cgf.patch" file.
If I apply that patch on top of your gdb-7.8-1.src.patch, the problem is
gone. (The python warning is still there, but it seems to be harmless.)
Ken
--- gdb/windows-nat.c.orig 2014-09-12 09:08:38.714405700 -0400
+++ gdb/windows-nat.c 2014-09-12 12:33:12.853775100 -0400
@@ -121,8 +121,7 @@
# define bad_GetModuleFileNameEx bad_GetModuleFileNameExW
#endif
-static int have_saved_context; /* True if we've saved context from a
- cygwin signal. */
+static DWORD signal_thread_id; /* Non-zero if we saved context. */
static CONTEXT saved_context; /* Containes the saved context from a
cygwin signal. */
@@ -304,7 +303,8 @@
{
if (!th->suspended && get_context)
{
- if (get_context > 0 && id != current_event.dwThreadId)
+ if (get_context > 0 && id != current_event.dwThreadId
+ && id != signal_thread_id)
{
if (SuspendThread (th->h) == (DWORD) -1)
{
@@ -438,7 +438,7 @@ do_windows_fetch_inferior_registers (str
if (current_thread->reload_context)
{
- if (have_saved_context)
+ if (signal_thread_id)
{
/* Lie about where the program actually is stopped since
cygwin has informed us that we should consider the signal
@@ -446,7 +446,7 @@ do_windows_fetch_inferior_registers (str
"saved_context. */
memcpy (¤t_thread->context, &saved_context,
__COPY_CONTEXT_SIZE);
- have_saved_context = 0;
+ signal_thread_id = 0;
}
else
{
@@ -934,8 +934,12 @@
&saved_context,
__COPY_CONTEXT_SIZE, &n)
&& n == __COPY_CONTEXT_SIZE)
- have_saved_context = 1;
- current_event.dwThreadId = retval;
+ {
+ signal_thread_id = retval;
+ saved_context.ContextFlags = 0; /* Don't attempt to call
SetContext */
+ }
+ else
+ retval = 0;
}
}
@@ -1402,7 +1406,7 @@
DWORD continue_status, event_code;
thread_info *th;
static thread_info dummy_thread_info;
- int retval = 0;
+ DWORD thread_id = 0;
last_sig = GDB_SIGNAL_0;
@@ -1415,7 +1419,6 @@
event_code = current_event.dwDebugEventCode;
ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
th = NULL;
- have_saved_context = 0;
switch (event_code)
{
@@ -1433,14 +1436,14 @@
/* Kludge around a Windows bug where first event is a create
thread event. Caused when attached process does not have
a main thread. */
- retval = fake_create_process ();
- if (retval)
+ thread_id = fake_create_process ();
+ if (thread_id)
saw_create++;
}
break;
}
/* Record the existence of this thread. */
- retval = current_event.dwThreadId;
+ thread_id = current_event.dwThreadId;
th = windows_add_thread (ptid_build (current_event.dwProcessId, 0,
current_event.dwThreadId),
current_event.u.CreateThread.hThread,
@@ -1483,7 +1486,7 @@
current_event.dwThreadId),
current_event.u.CreateProcessInfo.hThread,
current_event.u.CreateProcessInfo.lpThreadLocalBase);
- retval = current_event.dwThreadId;
+ thread_id = current_event.dwThreadId;
break;
case EXIT_PROCESS_DEBUG_EVENT:
@@ -1502,7 +1505,7 @@
{
ourstatus->kind = TARGET_WAITKIND_EXITED;
ourstatus->value.integer = current_event.u.ExitProcess.dwExitCode;
- retval = main_thread_id;
+ thread_id = main_thread_id;
}
break;
@@ -1517,7 +1520,7 @@
catch_errors (handle_load_dll, NULL, (char *) "", RETURN_MASK_ALL);
ourstatus->kind = TARGET_WAITKIND_LOADED;
ourstatus->value.integer = 0;
- retval = main_thread_id;
+ thread_id = main_thread_id;
break;
case UNLOAD_DLL_DEBUG_EVENT:
@@ -1530,7 +1533,7 @@
catch_errors (handle_unload_dll, NULL, (char *) "", RETURN_MASK_ALL);
ourstatus->kind = TARGET_WAITKIND_LOADED;
ourstatus->value.integer = 0;
- retval = main_thread_id;
+ thread_id = main_thread_id;
break;
case EXCEPTION_DEBUG_EVENT:
@@ -1546,7 +1549,7 @@
continue_status = DBG_EXCEPTION_NOT_HANDLED;
break;
case 1:
- retval = current_event.dwThreadId;
+ thread_id = current_event.dwThreadId;
break;
case -1:
last_sig = 1;
@@ -1562,7 +1565,7 @@
"OUTPUT_DEBUG_STRING_EVENT"));
if (saw_create != 1)
break;
- retval = handle_output_debug_string (ourstatus);
+ thread_id = handle_output_debug_string (ourstatus);
break;
default:
@@ -1576,7 +1579,7 @@
break;
}
- if (!retval || saw_create != 1)
+ if (!thread_id || saw_create != 1)
{
if (continue_status == -1)
windows_resume (ops, minus_one_ptid, 0, 1);
@@ -1586,12 +1589,12 @@
else
{
inferior_ptid = ptid_build (current_event.dwProcessId, 0,
- retval);
- current_thread = th ?: thread_rec (current_event.dwThreadId, TRUE);
+ thread_id);
+ current_thread = th ?: thread_rec (thread_id, TRUE);
}
out:
- return retval;
+ return (int) thread_id;
}
/* Wait for interesting events to occur in the target process. */
--
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