1648497 - Enable building Firefox on AArch64 macOS

Status: NEW

(Firefox Build System :: General, enhancement)

Comment 1

[Mike Hommey [:glandium]]

On the build system side, I think updating config.sub when support for arm64 mac is added would be enough.

Comment 2

[Mike Hommey [:glandium]]

I just checked https://git.savannah.gnu.org/gitweb/?p=config.git, and it hasn't been updated yet.

Comment 3

[Gian-Carlo Pascutto [:gcp]]

Previous comments from Mike (sorry if some of these are already superseded):

Ability to compile with any updated Mac SDK (if our current one doesn’t know about ARM64)

It doesn't. Only 11 SDK from Xcode 12 beta does, and it requires macOS 11 to link anything at all (ld insists that system dylibs must be fat arm64-x86_64, although it technically doesn't need to (cctools-port doesn't look like to care, so it's presumably only a problem for non-cross-compiles))

Clang/LLVM ARM64 Darwin support

This seems to be supported already (at least in clang 10, haven't checked clang 9). Albeit, arm64-apple-darwin/arm64-apple-macos is supported, but arm64e variants are not.

Rust ARM64 Darwin support (blocked on the Clang/LLVM support)

Presumably only needs to know about the target, cf. comment about clang.
Related: https://github.com/rust-lang/rust/issues/73628

Comment 4

[Gian-Carlo Pascutto [:gcp]]

Cross-build tools (e.g. the linker, various binary tools, etc.)

It seems everything might be okay, except for the linker not supporting the new tbd format in the 11 SDK. https://github.com/tpoechtrager/apple-libtapi/issues/13 (which is true for using that SDK at all, even for x86-64)

Comment 5

[Mike Hommey [:glandium]]

Instructions to build on Apple Silicon: https://docs.google.com/document/d/1N5yfEVEISofMmjAxfj3xXONGwyQYBSilsfXqux_M6TM/edit?usp=sharing