Devs Should I expect failures with a stage2 compiler built with -DDEBUG? I'd much prefer the answer to be "no". But I several failure Unexpected failures: deriving/should_compile/T11148.run T11148 [bad exit code (2)] (normal) indexed-types/should_compile/T11361.run T11361 [exit code non-0] (normal) polykinds/T11362.run T11362 [exit code non-0] (normal) stranal/should_compile/T9208.run T9208 [exit code non-0] (optasm) typecheck/should_fail/TcCoercibleFail.run TcCoercibleFail [stderr mismatch] (normal) Fragile tests: libraries/base/tests/CPUTime001.run CPUTime001 [fragile pass] (normal) profiling/should_run/heapprof001.run heapprof001 [fragile fail] (ghci-ext-prof) profiling/should_run/heapprof001.run heapprof001 [fragile fail] (prof) profiling/should_run/T15897.run T15897 [fragile fail] (profasm) ghci/should_run/T3171.run T3171 [fragile pass] (normal) profiling/should_run/T5559.run T5559 [fragile fail] (ghci-ext-prof) profiling/should_run/T5559.run T5559 [fragile fail] (prof) concurrent/should_run/T5611.run T5611 [fragile pass] (normal) concurrent/should_run/T5611a.run T5611a [fragile pass] (normal) Of these, the first three are ghc-stage2: compiler/cbits/genSym.c:14: checkUniqueRange: Assertion `u != UNIQUE_MASK' failed. What's going on there? Simon