Regression: `Object.fromFoldable` causes stack overflow in Google Chrome
gasi opened this issue · comments
First of all, thanks for all your work on keeping the PureScript ecosystem up and running!
We recently upgraded from PS 0.11 to 0.12 and ran into the following regression Foreign.Object.fromFoldable (vs the old Data.StrMap.fromFoldable) causes a stack overflow for large inputs in Google Chrome (Safari and FF seemed to have higher limits):
❌ Repro: PureScript 0.12
module Main where
import Prelude
import Effect (Effect)
import Effect.Console (log)
import Data.Array ((..))
import Data.Tuple (Tuple(..))
import Foreign.Object as Object
main :: Effect Unit
main = do
let m = Object.fromFoldable $ do
x <- 1 .. 10000
pure $ Tuple (show x) x
log $ show mError
foreign.js:22 Uncaught RangeError: Maximum call stack size exceeded
at foreign.js:22
at foreign.js:6
at foreign.js:20
at foreign.js:20
at foreign.js:20
at foreign.js:20
at foreign.js:20
at foreign.js:20
at foreign.js:20
at foreign.js:20✅ PureScript 0.11
Paste this into Try PureScript and observe that there is no stack overflow:
module Main where
import Prelude
import Control.Monad.Eff (Eff)
import Data.Array ((..))
import Data.Tuple (Tuple(..))
import Data.Foldable (fold)
import TryPureScript (DOM, h1, h2, p, text, list, indent, link, render, code)
import Data.StrMap as SM
main :: Eff (dom :: DOM) Unit
main = do
let m = SM.fromFoldable $ do
x <- 1 .. 10000
pure $ Tuple (show x) x
render $ fold
[ p (text $ show m) ]Observations
Superficially the two implementations look the same except the addition of Array.fromFoldable, but I confirmed removing it doesn’t change the outcome:
Related afaict purescript/purescript#3100
for_ is never stack safe with ST/Effect, but it was probably consuming less stack before with ST optimizations.