Use a stage-dependent shared library directory for testing.

[eddyb]

Unbreaks check-stage0-CRATE where CRATE may be one of coretest, std, syntax, rustc_driver, etc.

[rust-highfive]

r? @alexcrichton

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[alexcrichton]

Have you checked to make sure this actually works? Testing locally we still pass -Z no-landing-pads to stage0 compiles which causes stage0 stdtest to fail.

[alexcrichton]

This also appears to have been added in c60d9ad, and although I don't remember the precise reason why this commit does indeed break cross-host builds. I configured a host of 32/64 bit locally and got this during compilation:

$ make -j10
cfg: version 1.2.0-dev (f45181276 2015-06-18)
cfg: build triple x86_64-unknown-linux-gnu
cfg: host triples i686-unknown-linux-gnu x86_64-unknown-linux-gnu
cfg: target triples i686-unknown-linux-gnu x86_64-unknown-linux-gnu
cfg: non-build host triples i686-unknown-linux-gnu
cfg: non-build target triples i686-unknown-linux-gnu
cfg: host for i686-unknown-linux-gnu is i386
cfg: host for x86_64-unknown-linux-gnu is x86_64
cfg: os for i686-unknown-linux-gnu is unknown-linux-gnu
cfg: os for x86_64-unknown-linux-gnu is unknown-linux-gnu
cfg: good valgrind for i686-unknown-linux-gnu is 1
cfg: good valgrind for x86_64-unknown-linux-gnu is 1
cfg: using CC=ccache gcc (CFG_CC)
cfg: enabling valgrind run-pass tests (CFG_ENABLE_VALGRIND_RPASS)
cfg: valgrind-rpass command set to "/usr/bin/valgrind" --error-exitcode=100 --fair-sched=try --quiet --soname-synonyms=somalloc=NONE --suppressions=/home/alex/code/rust2/src/etc/x86.supp  --tool=memcheck --leak-check=full
cfg: no xelatex found, disabling LaTeX docs
cfg: no pandoc found, omitting PDF and EPUB docs
rustc: i686-unknown-linux-gnu/stage0/lib/rustlib/i686-unknown-linux-gnu/lib/libcore
i686-unknown-linux-gnu/stage0/bin/rustc: error while loading shared libraries: librustc_driver-d8ace771.so: cannot open shared object file: No such file or directory
make: *** [i686-unknown-linux-gnu/stage0/lib/rustlib/i686-unknown-linux-gnu/lib/stamp.core] Error 127
make: INTERNAL: Exiting with 11 jobserver tokens available; should be 10!

[eddyb]

Oh, right, check-stage0-stdtest didn't finish, but it did run (and ended hanging up after a failure of sync::mutex::tests::test_mutex_arc_access_in_unwind).
All the other tests I've tried compiled and ran successfully.

The cross-host build issue is one I had not anticipated, and I will have to look into it, but I still don't believe hardcoding stage1 in is a good idea - I have no idea how it even runs at stage2, other than the fact that there might be no dynamic dependencies.

[eddyb]

I'll close this since check-stage0-rustc_driver just started working for no apparent reason after a rebase.

[bluss]

This makefile tweak allows collectionstest to run in stage0, do you think it can be fixed & merged?

[eddyb]

@bluss I think I was mistaken, it broke again. Maybe the removal of stage1 libs during reconfigure made it work for a little bit.
I'm not sure what the correct solution is, our makefiles are a bit of a jungle.