CPAL not outputting sound under Mac OS X x86_64. about cpal

[shockham]

@SirVer Do you get any sound with a debug build?

Had a look into this (on Mid 2012 15" mbp running yosemite) and appeared to be to do with the empty loop (presumably being optimized out in a release build?) at: https://github.com/tomaka/cpal/blob/master/src/coreaudio/mod.rs#L53

So if a statement is put inside it, like thread::sleep for example, it worked for me. Though that doesn't really feel like a clean fix.

[SirVer]

Sorry for the late reply, life is busy right now. @shockham bingo, that is it.

cargo run --example beep
    Finished dev [unoptimized + debuginfo] target(s) in 0.0 secs
     Running `target/debug/examples/beep`
<beeps roughly once per second>

cargo run --release --example beep
    Finished release [optimized] target(s) in 0.0 secs
     Running `target/release/examples/beep`
thread 'main' panicked at 'Failed to get default endpoint', /Users/rustbuild/src/rust-buildbot/slave/stable-dist-rustc-mac/build/src/libcore/option.rs:715
stack backtrace:
   1:        0x1049858ac - std::sys::imp::backtrace::tracing::imp::write::h21ca2762819c7ae8
   2:        0x10498706e - std::panicking::default_hook::{{closure}}::h38f99a37d00bb19b
   3:        0x104986d10 - std::panicking::default_hook::ha2186ee24b50729c
   4:        0x104987527 - std::panicking::rust_panic_with_hook::h979db19ee91d2a53
   5:        0x1049873d4 - std::panicking::begin_panic::h6a69f5b54391c64d
   6:        0x1049872f2 - std::panicking::begin_panic_fmt::h9de2343580b3c2c4
   7:        0x104987257 - rust_begin_unwind
   8:        0x1049a95a0 - core::panicking::panic_fmt::haa2997386017a96f
   9:        0x1049a962d - core::option::expect_failed::h6cd7e4444435a838
  10:        0x10497c958 - beep::main::h1e5c3d7705718ed0
  11:        0x1049880da - __rust_maybe_catch_panic
  12:        0x1049877a6 - std::rt::lang_start::hfc9882558f9403bf

[z3t0]

I cant get it to work on debug either... no crash but no sound either

[z3t0]

Also #154 doesn't seem to fix the no sound issue for me..

[shockham]

@z3t0 Sounds like that might be something different to the problem #154 fixed. Could you provide a little bit more information? does cargo run --release --example enumerate print something similar to the original post in the thread?

[mlindner]

Also having this issue here trying to use rodio. I wasn't seeing this until I tried using an external library that used cpal. If I used cpal directly I didn't have the issue, presumably because I was always in debug mode.

[mlindner]

Some additional info.
Running cargo run --example beep runs and produces sound but produces warnings.

   Compiling cpal v0.4.4 (file:///Users/mlindner/projects/cpal)
warning: unused `#[macro_use]` import, #[warn(unused_imports)] on by default
  --> src/lib.rs:73:1
   |
73 | #[macro_use]
   | ^^^^^^^^^^^^

warning: type alias is never used: `NumChannels`, #[warn(dead_code)] on by default
  --> src/coreaudio/mod.rs:87:1
   |
87 | type NumChannels = usize;
   | ^^^^^^^^^^^^^^^^^^^^^^^^^

warning: type alias is never used: `NumFrames`, #[warn(dead_code)] on by default
  --> src/coreaudio/mod.rs:88:1
   |
88 | type NumFrames = usize;
   | ^^^^^^^^^^^^^^^^^^^^^^^

    Finished dev [unoptimized + debuginfo] target(s) in 1.47 secs
     Running `target/debug/examples/beep`

Running cargo run --release --example beep panics.

    Finished release [optimized] target(s) in 0.0 secs
     Running `target/release/examples/beep`
thread 'main' panicked at 'Failed to get default endpoint', /Users/rustbuild/src/rust-buildbot/slave/stable-dist-rustc-mac/build/src/libcore/option.rs:715
note: Run with `RUST_BACKTRACE=1` for a backtrace.

Running your example cargo run --release --example enumerate prints the following.

Endpoints: 
1. Endpoint "Default AudioUnit Endpoint" Audio formats: 
1.1. Format { channels: [FrontLeft, FrontRight], samples_rate: SamplesRate(44100), data_type: F32 }

[mlindner]

I tried @shockham's build and that seems to have fixed this issue but when trying to use rodio I get the same issue as @z3t0.

[jansol]

@mlindner Are you still having this issue? I tuned the beep example on macOS 10.13.1 (MacBookPro13,3) a couple of weeks ago and it worked perfectly.

[mitchmindtree]

Closing this as the original issue has been confirmed fixed in #196. If any commenters on this thread still have problems feel free to open up a new issue for your specific issue :)