[PATCH v2 0/1] MR3873: tools/winebuild: Force CIE content on x86_64.

[eric pouech (＠epo)]

Force as to emit expected CIE/FDE information for x86_64 CPU
in .debug_frame section.

This has been unveiled by 425bd55b02e375b9ac8f79b254ce3ca5c9e72719
(before this commit, the .cfi directives where not emitted by
winebuild).

x86_64-w64-mingw32-as on x86_64 emits "strange" unwinding
information (from winebuild).

00000000 0000000000000014 ffffffff CIE
  Version:               1
  Augmentation:          ""
  Code alignment factor: 1
  Data alignment factor: -8
  Return address column: 32

DW_CFA_def_cfa: r7 (rsp) ofs 8
  DW_CFA_offset: r32 (xmm15) at cfa-8
  DW_CFA_nop
  DW_CFA_nop
  DW_CFA_nop
  DW_CFA_nop
  DW_CFA_nop
  DW_CFA_nop

Consequence: in unwinding, xmm15 gets updated, but rip isn't, causing
an infinite loop in dbghelp.

Wine-Bug-Id: https://bugs.winehq.org/show_bug.cgi?id=55560

Signed-off-by: Eric Pouech

--
  v2: tools/winebuild: Emit SEH unwind information instead of dwarf.

https://gitlab.winehq.org/wine/wine/-/merge_requests/3873