That test builds an executable named 'linker_unload' which segfaults for me. Valgrind says this: ==42800== Invalid read of size 8 ==42800== at 0x66945F: checkUnload (in /home/beehive/ryan_scratch/validate14/testsuite/tests/rts/linker_unload) ==42800== by 0x657F7A: GarbageCollect (in /home/beehive/ryan_scratch/validate14/testsuite/tests/rts/linker_unload) ==42800== by 0x651790: scheduleDoGC (in /home/beehive/ryan_scratch/validate14/testsuite/tests/rts/linker_unload) ==42800== by 0x6518B4: performGC_ (in /home/beehive/ryan_scratch/validate14/testsuite/tests/rts/linker_unload) ==42800== by 0x403BB1: main (in /home/beehive/ryan_scratch/validate14/testsuite/tests/rts/linker_unload) ==42800== Address 0x5bfdd20 is 80 bytes inside a block of size 120 free'd ==42800== at 0x4C273F0: free (vg_replace_malloc.c:446) ==42800== by 0x66945E: checkUnload (in /home/beehive/ryan_scratch/validate14/testsuite/tests/rts/linker_unload) ==42800== by 0x657F7A: GarbageCollect (in /home/beehive/ryan_scratch/validate14/testsuite/tests/rts/linker_unload) ==42800== by 0x651790: scheduleDoGC (in /home/beehive/ryan_scratch/validate14/testsuite/tests/rts/linker_unload) ==42800== by 0x6518B4: performGC_ (in /home/beehive/ryan_scratch/validate14/testsuite/tests/rts/linker_unload) ==42800== by 0x403BB1: main (in /home/beehive/ryan_scratch/validate14/testsuite/tests/rts/linker_unload) This went the same across a couple different independent checkouts. -Ryan