On 7/14/20 10:35, Alexandre Julliard wrote:
Paul Gofman pgofman@codeweavers.com writes:
On 7/13/20 23:05, Alexandre Julliard wrote:
Paul Gofman pgofman@codeweavers.com writes:
There is no guarantee that jmp_buf is 16 bytes aligned.
It is using DECLSPEC_ALIGN(16) though. Where do you see it being misaligned?
Well, I was getting that after turning NtOpenDirectoryObject locally into syscall thunk from __TRY / __CATCH block used by IsBadStringPtrW() from debugstr_w(). But after you pointed out that alignment is there which I initially missed, I found that the stack alignment which is present in syscall thunk generated code seems not to be performed (apparently, not intentionally) if the size of arguments is <= 0x20. I should rather be fixing that, sorry for the noise.
Fixing that wouldn't hurt, but note that all API functions should already be using force_align_arg_pointer. If that doesn't work correctly we'll have other problems.
The stack is not aligned in Mingw PE modules for some reason (I checked with a winehq binary also that is not my local build problem only; I also checked by explicitly setting it for function to make sure it is not some configuration problem). It is aligned in .so though, my local problem here was due to making syscall thunks for still PE Nt functions. Yet failure to align stack in Staging syscall thunks back then was breaking builds on some systems even with .so ntdll [1].