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Program compiled with -O2 exhibits much worse performance

A user on reddit reports that compiling the program with -O2 makes his program use a lot more memory.

https://www.reddit.com/r/haskell/comments/84qovv/an_example_of_code_where_ghcs_o2_makes_things/

It runs in constant memory without -O2 and leaks memory with `-O2. It seems worth investigating as the example is quite small (< 1000 lines) and self-contained.

https://github.com/luispedro/TestingNGLESS

Trac metadata
Trac field Value
Version 8.2.2
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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