#include <signal.h>
#include <ctype.h>
-#ifdef HAVE_GNU_LIBC_VERSION_H
-#include <gnu/libc-version.h>
-#endif
-
/* GNU/Linux libthread_db support.
libthread_db is a library, provided along with libpthread.so, which
return TD_OK;
}
+/* Verify inferior's '\0'-terminated symbol VER_SYMBOL starts with "%d.%d" and
+ return 1 if this version is lower (and not equal) to
+ VER_MAJOR_MIN.VER_MINOR_MIN. Return 0 in all other cases. */
+
+static int
+inferior_has_bug (const char *ver_symbol, int ver_major_min, int ver_minor_min)
+{
+ struct minimal_symbol *version_msym;
+ CORE_ADDR version_addr;
+ char *version;
+ int err, got, retval = 0;
+
+ version_msym = lookup_minimal_symbol (ver_symbol, NULL, NULL);
+ if (version_msym == NULL)
+ return 0;
+
+ version_addr = SYMBOL_VALUE_ADDRESS (version_msym);
+ got = target_read_string (version_addr, &version, 32, &err);
+ if (err == 0 && memchr (version, 0, got) == &version[got -1])
+ {
+ int major, minor;
+
+ retval = (sscanf (version, "%d.%d", &major, &minor) == 2
+ && (major < ver_major_min
+ || (major == ver_major_min && minor < ver_minor_min)));
+ }
+ xfree (version);
+
+ return retval;
+}
+
static void
enable_thread_event_reporting (void)
{
td_thr_events_t events;
td_err_e err;
-#ifdef HAVE_GNU_LIBC_VERSION_H
- const char *libc_version;
- int libc_major, libc_minor;
-#endif
struct thread_db_info *info;
info = get_thread_db_info (GET_PID (inferior_ptid));
td_event_emptyset (&events);
td_event_addset (&events, TD_CREATE);
-#ifdef HAVE_GNU_LIBC_VERSION_H
- /* The event reporting facility is broken for TD_DEATH events in
- glibc 2.1.3, so don't enable it if we have glibc but a lower
- version. */
- libc_version = gnu_get_libc_version ();
- if (sscanf (libc_version, "%d.%d", &libc_major, &libc_minor) == 2
- && (libc_major > 2 || (libc_major == 2 && libc_minor > 1)))
-#endif
+ /* There is a bug fixed between linuxthreads 2.1.3 and 2.2 by
+ commit 2e4581e4fba917f1779cd0a010a45698586c190a
+ * manager.c (pthread_exited): Correctly report event as TD_REAP
+ instead of TD_DEATH. Fix comments.
+ where event reporting facility is broken for TD_DEATH events,
+ so don't enable it if we have glibc but a lower version. */
+ if (!inferior_has_bug ("__linuxthreads_version", 2, 2))
td_event_addset (&events, TD_DEATH);
err = info->td_ta_set_event_p (info->thread_agent, &events);
}
}
-/* Same as thread_db_find_new_threads_1, but silently ignore errors. */
+/* Similar as thread_db_find_new_threads_1, but try to silently ignore errors
+ if appropriate.
-static void
+ Return 1 if the caller should abort libthread_db initialization. Return 0
+ otherwise. */
+
+static int
thread_db_find_new_threads_silently (ptid_t ptid)
{
volatile struct gdb_exception except;
thread_db_find_new_threads_2 (ptid, 1);
}
- if (except.reason < 0 && libthread_db_debug)
+ if (except.reason < 0)
{
- exception_fprintf (gdb_stderr, except,
- "Warning: thread_db_find_new_threads_silently: ");
+ if (libthread_db_debug)
+ exception_fprintf (gdb_stderr, except,
+ "Warning: thread_db_find_new_threads_silently: ");
+
+ /* There is a bug fixed between nptl 2.6.1 and 2.7 by
+ commit 7d9d8bd18906fdd17364f372b160d7ab896ce909
+ where calls to td_thr_get_info fail with TD_ERR for statically linked
+ executables if td_thr_get_info is called before glibc has initialized
+ itself.
+
+ If the nptl bug is NOT present in the inferior and still thread_db
+ reports an error return 1. It means the inferior has corrupted thread
+ list and GDB should fall back only to LWPs.
+
+ If the nptl bug is present in the inferior return 0 to silently ignore
+ such errors, and let gdb enumerate threads again later. In such case
+ GDB cannot properly display LWPs if the inferior thread list is
+ corrupted. */
+
+ if (!inferior_has_bug ("nptl_version", 2, 7))
+ {
+ exception_fprintf (gdb_stderr, except,
+ _("Warning: couldn't activate thread debugging "
+ "using libthread_db: "));
+ return 1;
+ }
}
+ return 0;
}
/* Lookup a library in which given symbol resides.
info->td_thr_event_enable_p = dlsym (info->handle, "td_thr_event_enable");
info->td_thr_tls_get_addr_p = dlsym (info->handle, "td_thr_tls_get_addr");
+ if (thread_db_find_new_threads_silently (inferior_ptid) != 0)
+ {
+ /* Even if libthread_db initializes, if the thread list is
+ corrupted, we'd not manage to list any threads. Better reject this
+ thread_db, and fall back to at least listing LWPs. */
+ return 0;
+ }
+
printf_unfiltered (_("[Thread debugging using libthread_db enabled]\n"));
if (libthread_db_debug || *libthread_db_search_path)
if (target_has_execution)
enable_thread_event_reporting ();
- /* There appears to be a bug in glibc-2.3.6: calls to td_thr_get_info fail
- with TD_ERR for statically linked executables if td_thr_get_info is
- called before glibc has initialized itself. Silently ignore such
- errors, and let gdb enumerate threads again later. */
- thread_db_find_new_threads_silently (inferior_ptid);
-
return 1;
}
/* This should at minimum hit the first character. */
gdb_assert (cp != NULL);
strcpy (cp + 1, LIBTHREAD_DB_SO);
- result = try_thread_db_load (path);
+
+ if (!file_is_auto_load_safe (path, _("auto-load: Loading libthread-db "
+ "library \"%s\" from $pdir.\n"),
+ path))
+ result = 0;
+ else
+ result = try_thread_db_load (path);
do_cleanups (cleanup);
return result;
memcpy (path, dir, dir_len);
path[dir_len] = '/';
strcpy (path + dir_len + 1, LIBTHREAD_DB_SO);
- result = try_thread_db_load (path);
+
+ if (!file_is_auto_load_safe (path, _("auto-load: Loading libthread-db "
+ "library \"%s\" from explicit "
+ "directory.\n"),
+ path))
+ result = 0;
+ else
+ result = try_thread_db_load (path);
do_cleanups (cleanup);
return result;
{
if (sigismember (&mask, i))
{
- if (signal_stop_update (target_signal_from_host (i), 0))
+ if (signal_stop_update (gdb_signal_from_host (i), 0))
sigaddset (&thread_stop_set, i);
- if (signal_print_update (target_signal_from_host (i), 0))
+ if (signal_print_update (gdb_signal_from_host (i), 0))
sigaddset (&thread_print_set, i);
thread_signals = 1;
}
correctly. */
if (objfile != NULL
+ /* libpthread with separate debug info has its debug info file already
+ loaded (and notified without successful thread_db initialization)
+ the time observer_notify_new_objfile is called for the library itself.
+ Static executables have their separate debug info loaded already
+ before the inferior has started. */
+ && objfile->separate_debug_objfile_backlink == NULL
/* Only check for thread_db if we loaded libpthread,
or if this is the main symbol file.
We need to check OBJF_MAINLINE to handle the case of debugging
thread_db_find_new_threads_1 (ptid);
if (ourstatus->kind == TARGET_WAITKIND_STOPPED
- && ourstatus->value.sig == TARGET_SIGNAL_TRAP)
+ && ourstatus->value.sig == GDB_SIGNAL_TRAP)
/* Check for a thread event. */
check_event (ptid);
static void
thread_db_find_new_threads_2 (ptid_t ptid, int until_no_new)
{
- td_err_e err;
+ td_err_e err = TD_OK;
struct thread_db_info *info;
int pid = ptid_get_pid (ptid);
int i, loop;
The 4 is a heuristic: there is an inherent race here, and I have
seen that 2 iterations in a row are not always sufficient to
"capture" all threads. */
- for (i = 0, loop = 0; loop < 4; ++i, ++loop)
- if (find_new_threads_once (info, i, NULL) != 0)
- /* Found some new threads. Restart the loop from beginning. */
- loop = -1;
+ for (i = 0, loop = 0; loop < 4 && err == TD_OK; ++i, ++loop)
+ if (find_new_threads_once (info, i, &err) != 0)
+ {
+ /* Found some new threads. Restart the loop from beginning. */
+ loop = -1;
+ }
}
else
- {
- find_new_threads_once (info, 0, &err);
- if (err != TD_OK)
- error (_("Cannot find new threads: %s"), thread_db_err_str (err));
- }
+ find_new_threads_once (info, 0, &err);
+
+ if (err != TD_OK)
+ error (_("Cannot find new threads: %s"), thread_db_err_str (err));
}
static void
static void
thread_db_resume (struct target_ops *ops,
- ptid_t ptid, int step, enum target_signal signo)
+ ptid_t ptid, int step, enum gdb_signal signo)
{
struct target_ops *beneath = find_target_beneath (ops);
struct thread_db_info *info;
projects / binutils.git / blobdiff