Undefined references to 'pthread_barrier_{init,destroy,wait}' on Android

[luqmana]

With hello.rs:

fn main() {
    println!("Hello World!");
}

I get:

-> % rustc --target=arm-linux-androideabi --android-cross-path=/scratch/laden/android-dev/standalone hello.rs
error: linking with `/scratch/laden/android-dev/standalone/bin/arm-linux-androideabi-gcc` failed with code 1
note: /scratch/laden/android-dev/standalone/bin/arm-linux-androideabi-gcc arguments: -L/export/scratch/laden/local/lib/rustc/arm-linux-androideabi/lib -marm -o hello hello.o -L/export/scratch/laden/local/lib/rustc/arm-linux-androideabi/lib -lstd-6c65cf4b443341b1-0.9-pre -L/export/scratch/laden/run/.rust -L/export/scratch/laden/run -ldl -llog -lsupc++ -lgnustl_shared -lm -lmorestack -lrustrt -Wl,-rpath,$ORIGIN/../local/lib/rustc/arm-linux-androideabi/lib -Wl,-rpath,/export/scratch/laden/local/lib/rustc/arm-linux-androideabi/lib -Wl,-rpath,/scratch/laden/local/lib/rustc/arm-linux-androideabi/lib
note: /export/scratch/laden/android-dev/standalone/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: /export/scratch/laden/local/lib/rustc/arm-linux-androideabi/lib/librustrt.so: error: undefined reference to 'pthread_barrier_init'
/export/scratch/laden/android-dev/standalone/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: /export/scratch/laden/local/lib/rustc/arm-linux-androideabi/lib/librustrt.so: error: undefined reference to 'pthread_barrier_destroy'
/export/scratch/laden/android-dev/standalone/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: /export/scratch/laden/local/lib/rustc/arm-linux-androideabi/lib/librustrt.so: error: undefined reference to 'pthread_barrier_wait'
collect2: ld returned 1 exit status

No combination of passing -lpthreads or -pthread with --link-args seems to help.

Just stubbing them out makes it compile successfully and at least for that simple program run fine but obviously that's not a solution.

[sanxiyn]

Does this happen with clean Rust build? I used to get this when libuv is built without options for Android, and this temporarily regressed when we switched to gyp for building libuv, and if you built Rust while it regressed and used incremental build without clean it continued to happen.

[luqmana]

I think I tried a make clean but I'll just try wiping the build dir to make sure.

[luqmana]

Yep, wiping out the build dir fixed this.