Fails to find headers on macOS 10.13

[regexident]

Trying to build coreaudio-sys on macOS 10.13 I get this:

$ cargo build

error: failed to run custom build command for `coreaudio-sys v0.2.0 (file:///Users/<snip>/Downloads/coreaudio-sys)`
process didn't exit successfully: `/Users/<snip>/Downloads/coreaudio-sys/target/debug/build/coreaudio-sys-da31a326d38f965f/build-script-build` (exit code: 101)
--- stdout
cargo:rustc-link-lib=framework=AudioToolbox
cargo:rustc-link-lib=framework=AudioUnit
cargo:rustc-link-lib=framework=CoreAudio
cargo:rustc-link-lib=framework=OpenAL
cargo:rustc-link-lib=framework=CoreMIDI

--- stderr
error: header '/System/Library/Frameworks/CoreMIDI.framework/Headers/CoreMIDI.h' does not exist.
thread 'main' panicked at 'unable to generate bindings: ()', src/libcore/result.rs:916:5
note: Run with `RUST_BACKTRACE=1` for a backtrace.

Peeking into any of the frameworks located in /System/Library/Frameworks/… one finds that that there are in fact no headers to be found anywhere inside.

Having installed Xcode however one finds them buried deep down inside of Xcode.app:

/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/System/Library/Frameworks/… (MacOSX being one of AppleTVOS, AppleTVSimulator, iPhoneOS, iPhoneSimulator, MacOSX, WatchOS, WatchSimulator, …)

[mitchmindtree]

Hmmm interesting, two macOS 10.13 users have reported successful compilation, however you are not the first to find the CoreMIDI headers missing from the framework. If you remove the core_midi feature, does compilation succeed for you? E.g.

cargo build --no-default-features --features "audio_toolbox audio_unit core_audio open_al"

does it link and build correctly with this command?

Perhaps we should update the build.rs script so that it checks Xcode.app if it can't find the headers in the framework?

[mitchmindtree]

cc @HybridEidolon ^

[regexident]

Running this:

cargo build --no-default-features --features "audio_toolbox audio_unit core_audio open_al"

Results in:

error: header '/System/Library/Frameworks/OpenAL.framework/Headers/alc.h' does not exist.

[mitchmindtree]

Hmm ok what if you also remove 'open_al' from the list of features?

…

On Tue, 13 Feb 2018 at 8:03 am, Vincent Esche ***@***.***> wrote: Running this: cargo build --no-default-features --features "audio_toolbox audio_unit core_audio open_al" Results in: error: header '/System/Library/Frameworks/OpenAL.framework/Headers/alc.h' does not exist. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#5 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AEX_bRDvC3zG9SwYGMHs1qwII3sTJGmbks5tUKcSgaJpZM4SCD0x> .

[regexident]

Same.

error: header '/System/Library/Frameworks/CoreAudio.framework/Headers/CoreAudio.h' does not exist.

None of the frameworks in /System/Library/Frameworks/ contain any headers for me.
I just checked with a second, individual machine: no headers in said location either.

[regexident]

Calling xcode-select -p will give you something akin to /Applications/Xcode.app/Contents/Developer, from which one could further form the appropriate header file paths.

I reckon something like this might work:

let platform = if cfg!(target_os = "macos") {
    "MacOSX"
} else if cfg!(target_os = "ios") {
    "iPhoneOS"
} else {
    panic!("Ooops.");
};
let prefix = …; // path from `xcode-select -p`
let infix = format!("Platforms/{}.platform/Developer/SDKs/{}.sdk", platform, platform);
let suffix = "System/Library/Frameworks";
let directory = format!("{}/{}/{}/", prefix, infix, suffix);

[mitchmindtree]

Just for reference, this is the Core Audio doc that I've been referring to for finding the headers. I wonder if the approach of storing them within the Xcode App itself is the new way?

[mitchmindtree]

Thanks for the tip btw! I'd welcome a PR which added a follow-up check for these locations if the file could not be found in the current attempted location using something like you have here! I don't have a mac to test with atm is all, and the one I do have at home already works using the current header paths so wouldn't be useful for testing this anyways.

[mitchmindtree]

This method is probably the easiest way to test if a header exists, just in case you weren't aware!

[trsoluti]

Please merge regexident's fix into your code, as Apple has just recently removed the core audio header files from /System/Library/Frameworks. Thanks.

[Rhuagh]

This has been released as version 0.2.1.