Compilation of rust 0.6 fails with "task failed at 'explicit failure'"

[elszben]

I was about to try rust on debian 7 (64bit) and it failed while compiling with the following error:

laci@lumen:~/rust/rust-0.6$ make RUST_LOG=rustc=1,::rt::backtrace
cfg: build triple x86_64-unknown-linux-gnu
cfg: host triples x86_64-unknown-linux-gnu
cfg: target triples x86_64-unknown-linux-gnu
cfg: host for x86_64-unknown-linux-gnu is x86_64
cfg: os for x86_64-unknown-linux-gnu is unknown-linux-gnu
cfg: using gcc
cfg: no pandoc found, omitting doc/rust.pdf
cfg: no llnextgen found, omitting grammar-verification
cfg: no pandoc found, omitting library doc build
compile_and_link: x86_64-unknown-linux-gnu/stage0/lib/rustc/x86_64-unknown-linux-gnu/lib/librustc.so
rust: task failed at 'explicit failure', /home/rustbuild/src/rust-buildbot/slave/snap3-linux/build/src/libcore/run.rs:343
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x4f)[0x2b24dc0b852f]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(+0x299f1)[0x2b24dc0c89f1]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(upcall_fail+0x1c6)[0x2b24dc0bacb6]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x1059ab)[0x2b24d8daf9ab]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x105952)[0x2b24d8daf952]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(_ZN3sys12begin_unwind16_701b8ec61f97ead3_06E+0x71)[0x2b24d8cf7441]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(_ZN3run14program_output16_3596fc6920d4f353_06E+0x2872)[0x2b24d8da9aa2]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x14e214)[0x2b24d8df8214]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN4back4link11link_binary17_483345abdae712883_06E+0x3a9d)[0x2b24da488bad]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x5db835)[0x2b24da251835]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6driver6driver12compile_rest16_87c0f340aa21a393_06E+0x40e2)[0x2b24da4ef2b2]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8b9e84)[0x2b24da52fe84]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6driver6driver12compile_upto17_84743710faafb0af3_06E+0x108)[0x2b24da4f1738]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8b9e84)[0x2b24da52fe84]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6driver6driver13compile_input15_a6b0fe22676e6b3_06E+0xca)[0x2b24da4f1b7a]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN12run_compiler16_9de519bbeb758373_06E+0x20aa)[0x2b24da52131a]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8b7951)[0x2b24da52d951]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8b417c)[0x2b24da52a17c]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8b9e84)[0x2b24da52fe84]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0xce38e)[0x2b24d8d7838e]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x14e214)[0x2b24d8df8214]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x24)[0x2b24dc0b9534]
error: internal compiler error: unexpected failure
note: the compiler hit an unexpected failure path. this is a bug
note: try running with RUST_LOG=rustc=1,::rt::backtrace to get further details and report the results to github.com/mozilla/rust/issues
rust: task failed at 'explicit failure', /home/rustbuild/src/rust-buildbot/slave/snap3-linux/build/src/librustc/rustc.rc:357
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x4f)[0x2b24dc0b852f]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(+0x299f1)[0x2b24dc0c89f1]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(upcall_fail+0x1c6)[0x2b24dc0bacb6]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x1059ab)[0x2b24d8daf9ab]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x105952)[0x2b24d8daf952]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(_ZN3sys12begin_unwind16_701b8ec61f97ead3_06E+0x71)[0x2b24d8cf7441]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x14e214)[0x2b24d8df8214]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN7monitor17_ab3b5d4d4b9efdb63_06E+0x1577)[0x2b24da523947]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8b9e84)[0x2b24da52fe84]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN4main16_706f4ee7413ae583_06E+0x7e)[0x2b24da52fa9e]
/home/laci/rust/rust-0.6/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x24)[0x2b24dc0b9534]
rust: domain main @0x22253c0 root task failed
make: *** [x86_64-unknown-linux-gnu/stage0/lib/rustc/x86_64-unknown-linux-gnu/lib/librustc.so] Error 101

The compiler (runtime?) seems to complain about something in /home/rustbuild. I do not know what exactly the meaning of those explicit failure lines are but there is no /home/rustbuild/ directory on my machine.

[Aatch]

It only mentions rustbuild because that is where the snapshot is built, and the snapshot is asserting.

Can you please try building the latest incoming, as that is where development happens.

From the look of the backtrace, you may be running out of memory when the linker is run, how much RAM do you have? Rust needs about 2G to build.

[elszben]

I have 4 gb memory and I closed everything unnecessary for one more build test and it died again with something similar. This time I've tried to build the latest code from git.
I guess you were right about the root cause, it died with the following:
compile_and_link: x86_64-unknown-linux-gnu/stage1/lib/rustc/x86_64-unknown-linux-gnu/lib/librustc.so
rust: task failed at 'failure in fork: Cannot allocate memory', /home/laci/rust/latest/rust/src/libcore/run.rs:382

I also watched the memory usage with the system monitor and it never reached 80% (it peaked around 78%). Honestly, I am not sure what my options are, if my system is not able to compile rust I guess I'll have to wait for a precompiled version.

[elszben]

I've added a 2 GB swap area and I've managed to compile rust at the first attempt. The funny thing is that according to my system monitor the memory usage still did not reach 80% and the swap area was not used, at all.

[Aatch]

@elszben overcommit on linux interacts strangely with fork. This is a known issue, but the only thing we can do is lower memory usage, which a bit nebulous for a single issue.

Closing.