1511523 - bindgen should probably use the system clang on macOS

Status: RESOLVED WONTFIX

(Firefox Build System :: General, enhancement)

Description

[Xidorn Quan [:xidorn] UTC+10]

I don't recall all the details why we prefer to use homebrew. Possible reasons may include:
(1) system clang may be buggy for bindgen at that time
(2) system clang doesn't provide llvm-config for path discovery

We should probably revisit whether (1) is still a problem, and if not, we should probably switch to use system clang instead since that's what we use for building.

Looking at the code of clang-sys, I don't believe (2) is a problem at all now, as clang-sys can invoke `xcodebuild -find clang` to look for system clang. We can do the same in bindgen.configure.

Using the same clang when possible should eliminate some issues with bindgen, or at least making it easier to reason about. Issues like bug 1509696 is an example of failures due to the divergence of clang we use between build and bindgen.

Comment 1

[Mike Hommey [:glandium]]

As of bug 1526857, we use the same clang as the build system for bindgen.