http://bugs.winehq.org/show_bug.cgi?id=24068
Summary: Crash in dbghelp on 64-bit (WoW) Product: Wine Version: 1.3.1 Platform: x86-64 OS/Version: Linux Status: UNCONFIRMED Severity: normal Priority: P2 Component: dbghelp AssignedTo: wine-bugs@winehq.org ReportedBy: adys.wh@gmail.com
See attached backtrace. Note: I cannot repro the crash that got me there in the first place, so I won't be able to give further logs. However, I was hinted on IRC the backtrace could contain enough data to figure the bug out.
[06:34:13] <KittyCat> looks like it's unwinding the stack, so it might just be a thrown exception. can't tell if it's unhandled or not.. [06:35:33] <@Thunderbird_> dwarf2_virtual_unwind does nothing with context it just passes it through at the end of the call to this helper function (perhaps it should have checked context before? I don't know the code) [06:40:56] <KittyCat> hmm. this doesn't look like it should even compile.. [06:42:08] <KittyCat> oh, wait. okay [06:43:08] <KittyCat> it's dereferenced so it can be copied to a temp and restored later [06:43:42] <KittyCat> and some of the switch cases may do something with it [06:44:44] <KittyCat> might have to ask Eric Pouech what's supposed to happen if it's given a NULL context pointer [06:46:11] <KittyCat> or AJ [06:55:56] <KittyCat> looks like that code was added in commit 036392c5d131d73e84ad0ed52a796b2cb9c1139d, on March 27th [07:02:13] <KittyCat> it seems, before that commit it'd have fallen back to a default_unwind() function, which would also take and use the context (unless sw_read_mem failed) [07:06:03] <KittyCat> it looks like it's calling StackWalk explicitly [07:09:08] <KittyCat> from the looks of it, wow is calling StackWalk with a NULL context. msdn doesn't seem to have StackWalk, but according to StackWalk64: [07:09:14] <KittyCat> "This parameter is required only when the MachineType parameter is not IMAGE_FILE_MACHINE_I386. However, it is recommended that this parameter contain a valid context record." [07:09:30] <KittyCat> and MachineType is being set to IMAGE_FILE_MACHINE_I386 [07:20:46] <KittyCat> from glancing at related commits, it doesn't look like StackWalk ever properly handled a NULL context parameter [07:21:46] <KittyCat> though it wasn't until about March 24th that it was actually used