rust-lang
Mac Catalyst: Read `IPHONEOS_DEPLOYMENT_TARGET` from environment variable to support Clang 13
Background
Clang 13 removed the x86_64-apple-ios13.0-macabi target, where 13.0 is hardcoded in cc-rs.
Proof:
➜ temp clang -target x86_64-apple-ios13.1-macabi i.c
➜ temp clang -target x86_64-apple-ios13.0-macabi i.c
clang-13: error: invalid version number in '-target x86_64-apple-ios13.0-macabi'
➜ temp clang --version
Homebrew clang version 13.0.1
Target: arm64-apple-darwin21.4.0
Thread model: posix
InstalledDir: /opt/homebrew/bin
➜ temp cat i.c
int main() {
return 0;
}
➜ temp
This PR is to remove this hardcoded version and read it from IPHONEOS_DEPLOYMENT_TARGET.
Credits
@ehuss helped me found this reason: https://rust-lang.zulipchat.com/#narrow/stream/122651-general/topic/Update.20Mac.20Catalyst.20support.20for.20Clang.2013/near/280745037
How to test
In this commit https://github.com/imWildCat/BLAKE3/commit/f7bfd7786dedbad7be3e263ee3282f2b36cacd1a, I changed cc-rs to my branch.
The build command and its output is like
➜ BLAKE3 git:(clang-13-mac-catalyst-demo) ✗ IPHONEOS_DEPLOYMENT_TARGET=13.1 cargo +nightly build -Z build-std --target x86_64-apple-ios-macabi
Compiling compiler_builtins v0.1.71
Compiling core v0.0.0 (/Users/wildcat/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/core)
Compiling libc v0.2.121
Compiling cc v1.0.69
Compiling memchr v2.4.1
Compiling std v0.0.0 (/Users/wildcat/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/std)
Compiling version_check v0.9.4
Compiling typenum v1.15.0
Compiling cc v1.0.73 (https://github.com/imWildCat/cc-rs?branch=clang-13-mac-catalyst#310a43a5)
Compiling generic-array v0.14.5
Compiling blake3 v1.3.1 (/Volumes/SharedVol/rust-projects/BLAKE3)
Compiling unwind v0.0.0 (/Users/wildcat/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/unwind)
Compiling rustc-std-workspace-core v1.99.0 (/Users/wildcat/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/rustc-std-workspace-core)
Compiling alloc v0.0.0 (/Users/wildcat/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/alloc)
Compiling cfg-if v0.1.10
Compiling adler v0.2.3
Compiling rustc-demangle v0.1.21
Compiling rustc-std-workspace-alloc v1.99.0 (/Users/wildcat/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/rustc-std-workspace-alloc)
Compiling panic_unwind v0.0.0 (/Users/wildcat/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/panic_unwind)
Compiling panic_abort v0.0.0 (/Users/wildcat/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/panic_abort)
Compiling gimli v0.25.0
Compiling std_detect v0.1.5 (/Users/wildcat/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/stdarch/crates/std_detect)
Compiling object v0.26.2
Compiling hashbrown v0.12.0
Compiling miniz_oxide v0.4.0
Compiling addr2line v0.16.0
Compiling proc_macro v0.0.0 (/Users/wildcat/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/proc_macro)
Compiling subtle v2.4.1
Compiling arrayref v0.3.6
Compiling arrayvec v0.7.2
Compiling constant_time_eq v0.1.5
Compiling cfg-if v1.0.0
Compiling block-buffer v0.10.2
Compiling crypto-common v0.1.3
Compiling digest v0.10.3
Finished dev [unoptimized + debuginfo] target(s) in 12.88s
So we no longer hardcode this as of https://github.com/rust-lang/cc-rs/pull/727. But I also think rustc itself is probably broken WRT how it handles catalyst, and would like to figure out the right fix there before doing too much in cc.
