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| author | Joel Brobecker <brobecker@gnat.com> | 2009-03-17 17:26:52 +0000 |
|---|---|---|
| committer | Joel Brobecker <brobecker@gnat.com> | 2009-03-17 17:26:52 +0000 |
| commit | f06eadd9d4d894f887509b56ef0986a44ade8770 (patch) | |
| tree | b03a91f095612023749cc5537b57377105fca05a | |
| parent | e85b18e10cf468cdbac014e960c9e36b071057ab (diff) | |
| download | gdb-f06eadd9d4d894f887509b56ef0986a44ade8770.zip gdb-f06eadd9d4d894f887509b56ef0986a44ade8770.tar.gz gdb-f06eadd9d4d894f887509b56ef0986a44ade8770.tar.bz2 | |
* frame.c (get_prev_frame_1): Do not perform the inner_frame
sanity check if this_frame is not NORMAL.
(frame_id_inner): Update the description of this function.
| -rw-r--r-- | gdb/ChangeLog | 6 | ||||
| -rw-r--r-- | gdb/frame.c | 31 |
2 files changed, 25 insertions, 12 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 7d0ce0a..fc4ba69 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2009-03-17 Joel Brobecker <brobecker@adacore.com> + + * frame.c (get_prev_frame_1): Do not perform the inner_frame + sanity check if this_frame is not NORMAL. + (frame_id_inner): Update the description of this function. + 2009-03-17 Hui Zhu <teawater@gmail.com> * stack.c: Change the introduce of "disassemble-next-line". diff --git a/gdb/frame.c b/gdb/frame.c index dfd6b3d..1d1856e 100644 --- a/gdb/frame.c +++ b/gdb/frame.c @@ -376,23 +376,29 @@ frame_id_eq (struct frame_id l, struct frame_id r) to sigaltstack). However, it can be used as safety net to discover invalid frame - IDs in certain circumstances. + IDs in certain circumstances. Assuming that NEXT is the immediate + inner frame to THIS and that NEXT and THIS are both NORMAL frames: - * If frame NEXT is the immediate inner frame to THIS, and NEXT - is a NORMAL frame, then the stack address of NEXT must be - inner-than-or-equal to the stack address of THIS. + * The stack address of NEXT must be inner-than-or-equal to the stack + address of THIS. Therefore, if frame_id_inner (THIS, NEXT) holds, some unwind error has occurred. - * If frame NEXT is the immediate inner frame to THIS, and NEXT - is a NORMAL frame, and NEXT and THIS have different stack - addresses, no other frame in the frame chain may have a stack - address in between. + * If NEXT and THIS have different stack addresses, no other frame + in the frame chain may have a stack address in between. Therefore, if frame_id_inner (TEST, THIS) holds, but frame_id_inner (TEST, NEXT) does not hold, TEST cannot refer - to a valid frame in the frame chain. */ + to a valid frame in the frame chain. + + The sanity checks above cannot be performed when a SIGTRAMP frame + is involved, because signal handlers might be executed on a different + stack than the stack used by the routine that caused the signal + to be raised. This can happen for instance when a thread exceeds + its maximum stack size. In this case, certain compilers implement + a stack overflow strategy that cause the handler to be run on a + different stack. */ static int frame_id_inner (struct gdbarch *gdbarch, struct frame_id l, struct frame_id r) @@ -1274,9 +1280,10 @@ get_prev_frame_1 (struct frame_info *this_frame) /* Check that this frame's ID isn't inner to (younger, below, next) the next frame. This happens when a frame unwind goes backwards. - This check is valid only if the next frame is NORMAL. See the - comment at frame_id_inner for details. */ - if (this_frame->next->unwind->type == NORMAL_FRAME + This check is valid only if this frame and the next frame are NORMAL. + See the comment at frame_id_inner for details. */ + if (get_frame_type (this_frame) == NORMAL_FRAME + && this_frame->next->unwind->type == NORMAL_FRAME && frame_id_inner (get_frame_arch (this_frame->next), this_id, get_frame_id (this_frame->next))) { |