Framework failures

I'm getting framework failures from the perf/ tests. Example below. Anyone know what is going on? Simon =====> T5837(normal) 1825 of 3901 [0, 0, 11] cd ./perf/compiler && '/5playpen/simonpj/HEAD-1/inplace/bin/ghc-stage2' -fforce-recomp -dno-debug-output -no-user-package-db -rtsopts -fno-ghci-history -c T5837.hs -ftype-function-depth=50 +RTS -V0 -tT5837.comp.stats --machine-readable -RTS >T5837.comp.stderr 2>&1 Failed to find field: bytes allocated *** framework failure for T5837(normal) do_test exception