arm: Properly mark _ZN8crashpad14CaptureContextEP10ucontext_t as %function

lld wants to remove bl/blx substitution for non-function symbols
(https://reviews.llvm.org/D73542). GNU ld apparently already doesn't
do it.

Since _ZN8crashpad14CaptureContextEP10ucontext_t wasn't marked as a function,
chromium's thumb code would then branch without mode transition into
crashpads non-thumb assembly (in arm32).

So mark the symbol as function, so that things work even if that patch
relands. This should also make things work with GNU ld, though I haven't
verified that it was broken before and works now.

I also did this for aarch64 since it seems like The Right Thing To Do
(assuming the assembler accepts it, which I also haven't checked --
the CQ will hopefully check that).

Bug: chromium:1049649
Change-Id: I3452c16f0d52a2dc0397fd3d60d06b5c39a4b524
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/2044144
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
This commit is contained in:
Nico Weber 2020-02-07 15:46:11 -05:00 committed by Commit Bot
parent 52ddeac77c
commit 7ed4d5c454

View File

@ -28,7 +28,11 @@
.globl CAPTURECONTEXT_SYMBOL2
#if defined(__i386__) || defined(__x86_64__)
.balign 16, 0x90
#elif defined(__arm__) || defined(__aarch64__) || defined(__mips__)
#elif defined(__arm__) || defined(__aarch64__)
.balign 4, 0x0
.type CAPTURECONTEXT_SYMBOL, %function
.type CAPTURECONTEXT_SYMBOL2, %function
#elif defined(__mips__)
.balign 4, 0x0
#endif