Fix gdb.python/py-thrhandle.exp failures for -m32 multilib
Commit Message
This patch fixes the following failures when testing with
"target_board unix/-m32" using a x86_64-pc-linux-gnu native GDB.
FAIL: gdb.python/py-thrhandle.exp: print thread for bogus handle thrs[3]
FAIL: gdb.python/py-thrhandle.exp: print thread for bogus handle thrs[4]
FAIL: gdb.python/py-thrhandle.exp: print thread id for thrs[0]
FAIL: gdb.python/py-thrhandle.exp: print thread id for thrs[1]
FAIL: gdb.python/py-thrhandle.exp: print thread id for thrs[2]
FAIL: gdb.python/py-thrhandle.exp: thread 0: fetch thread handle from thread
FAIL: gdb.python/py-thrhandle.exp: thread 0: verify that handles are the same
FAIL: gdb.python/py-thrhandle.exp: thread 1: fetch thread handle from thread
FAIL: gdb.python/py-thrhandle.exp: thread 1: verify that handles are the same
FAIL: gdb.python/py-thrhandle.exp: thread 2: fetch thread handle from thread
FAIL: gdb.python/py-thrhandle.exp: thread 2: verify that handles are the same
I've written it so that it might work for other 64-bit host / 32-bit target
combos too.
gdb/ChangeLog:
* linux-thread-db.c (thread_db_target::thread_handle_to_thread_info):
Add case for debugging 32-bit target on 64-bit host. Revise
comment.
---
gdb/linux-thread-db.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)
Comments
>>>>> "Kevin" == Kevin Buettner <kevinb@redhat.com> writes:
Kevin> I've written it so that it might work for other 64-bit host / 32-bit target
Kevin> combos too.
Kevin> gdb/ChangeLog:
Kevin> * linux-thread-db.c (thread_db_target::thread_handle_to_thread_info):
Kevin> Add case for debugging 32-bit target on 64-bit host. Revise
Kevin> comment.
Looks reasonable to me.
Tom
On Fri, 26 Jul 2019 15:01:33 -0600
Tom Tromey <tom@tromey.com> wrote:
> >>>>> "Kevin" == Kevin Buettner <kevinb@redhat.com> writes:
>
> Kevin> I've written it so that it might work for other 64-bit host / 32-bit target
> Kevin> combos too.
>
> Kevin> gdb/ChangeLog:
>
> Kevin> * linux-thread-db.c (thread_db_target::thread_handle_to_thread_info):
> Kevin> Add case for debugging 32-bit target on 64-bit host. Revise
> Kevin> comment.
>
> Looks reasonable to me.
Thanks for looking it over.
Pushed.
Kevin
@@ -1672,16 +1672,21 @@ thread_db_target::thread_handle_to_thread_info (const gdb_byte *thread_handle,
{
thread_t handle_tid;
- /* Thread handle sizes must match in order to proceed. We don't use an
- assert here because the resulting internal error will cause GDB to
- exit. This isn't necessarily an internal error due to the possibility
- of garbage being passed as the thread handle via the python interface. */
- if (handle_len != sizeof (handle_tid))
+ /* When debugging a 32-bit target from a 64-bit host, handle_len
+ will be 4 and sizeof (handle_tid) will be 8. This requires
+ a different cast than the more straightforward case where
+ the sizes are the same.
+
+ Use "--target_board unix/-m32" from a native x86_64 linux build
+ to test the 32/64-bit case. */
+ if (handle_len == 4 && sizeof (handle_tid) == 8)
+ handle_tid = (thread_t) * (const uint32_t *) thread_handle;
+ else if (handle_len == sizeof (handle_tid))
+ handle_tid = * (const thread_t *) thread_handle;
+ else
error (_("Thread handle size mismatch: %d vs %zu (from libthread_db)"),
handle_len, sizeof (handle_tid));
- handle_tid = * (const thread_t *) thread_handle;
-
for (thread_info *tp : inf->non_exited_threads ())
{
thread_db_thread_info *priv = get_thread_db_thread_info (tp);