==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.