On 27/01/2011 11:45, Daniel Fischer wrote:
While tuning some code, the test programme suddenly started producing stack
overflows.
Reverting the code to a previous version did not revert that behaviour,
code that previously produced a well-behaved binary now produced stack
overflowing ones.
But only with ghc-7.0.1, not with ghc-6.12.3 and ghc-6.12.1, and when
compiled with optimisations (both, -O and -O2) and without profiling.
A HEAD from October and a freshly darcs pulled HEAD displayed the same
behaviour as 7.0.1.
At some point I tried compiling with -fno-strictness (+ -O or -O2) which
again produced well-behaved albeit somewhat slower binaries.
An hour or so later, I again compile with -O2 without -fno-strictness to
see whether the Core revealed something and, as suddenly as the stack
overflows started, they disappeared, for the time being, I consistently get
well-behaved binaries.
A run of an overflowing binary with -hT -K32M produced a triangular graph
with> 10MB Blackhole allocation and> 30MB TSO allocation in the peak.
Obviously the behaviour is not reproducible, nevertheless, perhaps somebody
has an idea what went on. Or should I attribute it to cosmic rays?
I think you may have had an encounter with this bug:
http://hackage.haskell.org/trac/ghc/ticket/4924
I reported it yesterday, and Simon has already fixed it. The fix will
be in 7.0.2.
Cheers,
Simon
_______________________________________________
Glasgow-haskell-users mailing list
Glasgow-haskell-users@haskell.org
http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
