Skip to content

Slow type checking of type-level computation heavy code.

It seems we encountered a highly non-linear complexity in type checking.

I attached a "simple" program that produces the effect.

The time needed to load complete file in ghci depending on number of lines in longCompilingProgram:

  • 4 lines - 2 secs,
  • 8 lines - 10 secs,
  • 12 lines - 27 secs,
  • 16 lines - 59 secs.

time = 0,0156lines^3^ - 0,0937lines^2^ + 1,375lines - 3

Trac metadata
Trac field Value
Version 7.0.2
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler (Type checker)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information