1255869 - stagefright: Don't call into rust on machines without sse2

Status: RESOLVED FIXED

(Core :: Audio/Video: Playback, defect)

Description

[Ralph Giles (:rillian)]

Bug 1253202 is caused by the rust standard library being built with sse2 instructions for the i686 target. Some 32-bit x86 users don't have support for that extension, so while we don't use it for our own code, calls into rust-std still crash with an illegal instruction.

The proper fix is to build rust-std for the target we need to support, but in the meantime, work around the issue by not calling into the rust mp4parse module if sse2 isn't available at runtime

Comment 1

[Ralph Giles (:rillian)]

Attachment: Don't call into rust without sse2

Move MP4MetadataRust ctor into the MP4Metadata ctor body and make it conditional on sse2 detection. Without this the mRust pointer will be null and we won't call any of the methods elsewhere in the class.

Matthew, I assume you won't get to this until next week when I'm away. Do you mind taking over getting this landed and watching for re-occurance of the crashes in the parent bug? I don't have hardware to verify this, although I did test on my local linux machine by flipping the conditional and running `./mach gtest stagefright_MPEG4Metadata.*`

Comment 2

[Matthew Gregan [:kinetik]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/7c53fd9ec1fef76b87533ac4158fd4eca7eef049
Bug 1255869 - Don't call into mp4parse-rust on machines without sse2.  r=kinetik

Comment 3

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/7c53fd9ec1fe