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Huge space leak on a program that shouldn't leak

I have a program that works in a small amount of memory on a computer (less than 50mb) and leaks until it takes all available memory on another (with 16GB RAM).

I am unsure if this is a compiler bug, or a bug in one of the packages I use. I am also unsure on how to diagnose it.

You will find attached the ghc-pkg list for both computers, the offending program, and the output of -hp and -hy for the offending case. To reproduce the test it should be used like that :

genstats-simplepatterns dictionary output

Where dictionary is a large text file with a word per line (such as the rockyou list). The program itself is a fold that compiles statistics for each input line.

The "good" program is built with GHC-7.4.1. The bad one used to be built with it. As I suspected a package problem, I cleaned all my installation and started with a fresh GHC-7.4.2 + latest Haskell platform, but the result was identical.

The space leak seems to occur in HashMap, but converting all instances into Data.Map results in another leak.

Trac metadata
Trac field Value
Version 7.4.2
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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