Hello *, I noticed something odd while validating the GHC 7.10 branch: bytes allocated value is too low: (If this is because you have improved GHC, please update the test so that GHC doesn't regress again) Expected T9961(normal) bytes allocated: 772510192 +/-5% Lower bound T9961(normal) bytes allocated: 733884682 Upper bound T9961(normal) bytes allocated: 811135702 Actual T9961(normal) bytes allocated: 9766160 Deviation T9961(normal) bytes allocated: -98.7 % *** unexpected stat test failure for T9961(normal) ...then I also ran ./validate against today's GHC HEAD, and re-ran the T9961 test: Expected T9961(normal) bytes allocated: 772510192 +/-5% Lower bound T9961(normal) bytes allocated: 733884682 Upper bound T9961(normal) bytes allocated: 811135702 Actual T9961(normal) bytes allocated: 748225848 Deviation T9961(normal) bytes allocated: -3.1 % I'm not sure if it's just the test-case being broken, or there's something real regression between 7.10 and HEAD... However, I don't have time to investigate this. Cheers, hvr