Elliot Ronaghan 5acef864f2 Don't use compact red-black trees with the pgi compiler ... Some bug (either in the red-black tree code, or in the pgi compiler) seems to cause red-black trees to become unbalanced. This issue seems to go away if we don't use compact red-black trees. Since red-black trees don't seem to be used much anymore, I opted for what seems to be an easy fix here instead of digging in and trying to find the root cause of the bug. Some context in case it's helpful: I experienced a ton of segfaults while using pgi as Chapel's target compiler with jemalloc 4.0.4. The little bit of debugging I did pointed me somewhere deep in red-black tree manipulation, but I didn't get a chance to investigate further. It looks like 4.2.0 replaced most uses of red-black trees with pairing-heaps, which seems to avoid whatever bug I was hitting. However, `make check_unit` was still failing on the rb test, so I figured the core issue was just being masked. Here's the `make check_unit` failure: ```sh === test/unit/rb === test_rb_empty: pass tree_recurse:test/unit/rb.c:90: Failed assertion: (((_Bool) (((uintptr_t) (left_node)->link.rbn_right_red) & ((size_t)1)))) == (false) --> true != false: Node should be black test_rb_random:test/unit/rb.c:274: Failed assertion: (imbalances) == (0) --> 1 != 0: Tree is unbalanced tree_recurse:test/unit/rb.c:90: Failed assertion: (((_Bool) (((uintptr_t) (left_node)->link.rbn_right_red) & ((size_t)1)))) == (false) --> true != false: Node should be black test_rb_random:test/unit/rb.c:274: Failed assertion: (imbalances) == (0) --> 1 != 0: Tree is unbalanced node_remove:test/unit/rb.c:190: Failed assertion: (imbalances) == (0) --> 2 != 0: Tree is unbalanced <jemalloc>: test/unit/rb.c:43: Failed assertion: "pathp[-1].cmp < 0" test/test.sh: line 22: 12926 Aborted Test harness error ``` While starting to debug I saw the RB_COMPACT option and decided to check if turning that off resolved the bug. It seems to have fixed it (`make check_unit` passes and the segfaults under Chapel are gone) so it seems like on okay work-around. I'd imagine this has performance implications for red-black trees under pgi, but if they're not going to be used much anymore it's probably not a big deal.		2016-09-26 11:08:45 -07:00
..
jemalloc	Don't use compact red-black trees with the pgi compiler	2016-09-26 11:08:45 -07:00
msvc_compat	Remove errno overrides.	2016-05-03 10:01:16 -07:00