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Optimization causes repeated computation

The attached program, when compiled with -O0, calls array_adjust 6 times and hence prints 6 lines of trace output. However, with -O1, it prints 37 lines of trace output instead. Moreover, this number grows quadratically rather than linearly when I increase the value of n.

-fno-state-hack did not help.

I can reproduce the issue with both GHC 7.8.4 and 7.10.0.20150123.

Trac metadata
Trac field Value
Version 7.10.1-rc1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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