build failure in run-make/dep-info

[wizeman]

When trying to build commit a2866e3, I ran into the following build failure:

make[1]: Entering directory '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/src/test/run-make/dep-info'
cp *.rs /tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info
LD_LIBRARY_PATH="/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info:/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/stage2/lib:" /tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/stage2/bin/rustc --out-dir /tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info -L /tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info --emit dep-info,link --crate-type=lib /tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/lib.rs
sleep 2
touch /tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/foo.rs
rm -f /tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/done
make -drf Makefile.foo
GNU Make 4.1
Built for x86_64-unknown-linux-gnu
Copyright (C) 1988-2014 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Jobserver client (fds 3,4)
Reading makefiles...
Reading makefile 'Makefile.foo'...
make[2]: Entering directory '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/src/test/run-make/dep-info'
Reading makefile '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/foo.d' (search path) (don't care) (no ~ expansion)...
Updating makefiles....
 Considering target file '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/foo.d'.
  File '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/foo.d' does not exist.
  Looking for an implicit rule for '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/foo.d'.
  No implicit rule found for '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/foo.d'.
  Finished prerequisites of target file '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/foo.d'.
 Must remake target '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/foo.d'.
 Failed to remake target file '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/foo.d'.
 Considering target file 'Makefile.foo'.
  Looking for an implicit rule for 'Makefile.foo'.
  No implicit rule found for 'Makefile.foo'.
  Finished prerequisites of target file 'Makefile.foo'.
 No need to remake target 'Makefile.foo'.
Updating goal targets....
Considering target file '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/libfoo.rlib'.
 Finished prerequisites of target file '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/libfoo.rlib'.
No need to remake target '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/libfoo.rlib'.
make[2]: '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/libfoo.rlib' is up to date.
make[2]: Leaving directory '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/src/test/run-make/dep-info'
sleep 2
rm /tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/done
Makefile:10: recipe for target 'all' failed
make[1]: Leaving directory '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/src/test/run-make/dep-info'

------ stderr ---------------------------------------------
rm: cannot remove '/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/x86_64-unknown-linux-gnu/test/run-make/dep-info/done': No such file or directory
make[1]: *** [all] Error 1

------        ---------------------------------------------

/tmp/nix-build-rustc-2015-12-01-ga2866e3.drv-0/rust-a2866e3/mk/tests.mk:1087: recipe for target 'x86_64-unknown-linux-gnu/test/run-make/dep-info-2-T-x86_64-unknown-linux-gnu-H-x86_64-unknown-linux-gnu.ok' failed
make: *** [x86_64-unknown-linux-gnu/test/run-make/dep-info-2-T-x86_64-unknown-linux-gnu-H-x86_64-unknown-linux-gnu.ok] Error 2
make: *** Waiting for unfinished jobs....
maketest: extern-diff-internal-name
maketest: extern-flag-disambiguates
maketest: execution-engine
<3>builder for ‘/nix/store/5ran13bvvxpzf2kjf2h9186i52v063a4-rustc-2015-12-01-ga2866e3.drv’ failed with exit code 2

Any ideas?

[wizeman]

It looks like a foo.d file containing Makefile dependencies was supposed to get emitted by

rust/src/test/run-make/dep-info/Makefile

Line 11 in e3cd872

$(RUSTC) --emit dep-info,link --crate-type=lib $(TMPDIR)/lib.rs

, but for some reason didn't?

And what's with the sleep 2 commands, by the way? Are they trying to avoid a race condition or something?