Regression T2497 WAY=optasm: Simplifier ticks exhausted
$ make TEST=T2497 WAY=optasm EXTRA_HC_OPTS=-fsimpl-tick-factor=10000 TEST_HC=ghc-7.11.20150711
...
T2497.hs:18:1: warning: Defined but not used: ‘beq’
ghc: panic! (the 'impossible' happened)
(GHC version 7.11.20150711 for x86_64-unknown-linux):
Simplifier ticks exhausted
When trying RuleFired rule 1
To increase the limit, use -fsimpl-tick-factor=N (default 100)
If you need to do this, let GHC HQ know, and what factor you needed
To see detailed counts use -ddump-simpl-stats
Total ticks: 40000
...
The test is very small:
module ShouldCompile() where
eq :: Eq a => a -> a -> Bool
eq = (==)
{-# RULES
"rule 1" forall x y. x == y = y `eq` x
#-}
The problem does not occur with ghc-7.10.1. Curiously the problem goes away when I change the module header to module ShouldCompile where
.
Trac metadata
Trac field | Value |
---|---|
Version | 7.11 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | high |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |