diff options
| author | Tom Tromey <tromey@adacore.com> | 2023-03-21 13:40:03 -0600 |
|---|---|---|
| committer | Tom Tromey <tromey@adacore.com> | 2023-04-10 08:38:54 -0600 |
| commit | a0f6c61c9ab998cd77b0899a4bdea9576d6d775f (patch) | |
| tree | fbb874b05fbf7e59f2274d0cc24de96569c0d846 /gdb | |
| parent | 5f777caeebfd789f3b4f5ed13e9c3f49e9db0923 (diff) | |
| download | gdb-a0f6c61c9ab998cd77b0899a4bdea9576d6d775f.zip gdb-a0f6c61c9ab998cd77b0899a4bdea9576d6d775f.tar.gz gdb-a0f6c61c9ab998cd77b0899a4bdea9576d6d775f.tar.bz2 | |
Handle unwinding from SEGV on Windows
PR win32/30255 points out that a call to a NULL function pointer will
leave gdb unable to "bt" on Windows.
I tracked this down to the amd64 windows unwinder. If we treat this
scenario as if it were a leaf function, unwinding works fine.
I'm not completely sure this patch is the best way. I considered
having it check for 'pc==0' -- but then I figured this could affect
any inaccessible PC, not just the special 0 value.
No test case because I can't run dejagnu tests on Windows. I tested
this by hand using the test case in the bug.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30255
Diffstat (limited to 'gdb')
| -rw-r--r-- | gdb/amd64-windows-tdep.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/gdb/amd64-windows-tdep.c b/gdb/amd64-windows-tdep.c index 07df64b..9d69ec2 100644 --- a/gdb/amd64-windows-tdep.c +++ b/gdb/amd64-windows-tdep.c @@ -1098,13 +1098,14 @@ amd64_windows_frame_cache (frame_info_ptr this_frame, void **this_cache) cache->sp = extract_unsigned_integer (buf, 8, byte_order); cache->pc = pc; + /* If we can't find the unwind info, keep trying as though this is a + leaf function. This situation can happen when PC==0, see + https://sourceware.org/bugzilla/show_bug.cgi?id=30255. */ if (amd64_windows_find_unwind_info (gdbarch, pc, &unwind_info, &cache->image_base, &cache->start_rva, - &cache->end_rva)) - return cache; - - if (unwind_info == 0) + &cache->end_rva) + || unwind_info == 0) { /* Assume a leaf function. */ cache->prev_sp = cache->sp + 8; |