GitLab

Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC

Commits:

f93d523c

by Luite Stegeman at 2026-10-15T04:56:34-04:00

testsuite: Use mkWeakMVar in memo001/memo002

mkWeakPtr in the memo001/memo001 tests created weak pointers
with the MVar box as the key, which is fragile in the presence
of optimization. The fix is using mkWeakMVar, keying on the
primitive MVar# instead.

Fixes #27924 and #27396

3 changed files:

libraries/base/tests/Memo1.lhs
libraries/base/tests/Memo2.lhs
libraries/base/tests/all.T

Changes:

libraries/base/tests/Memo1.lhs

@@ -13,10 +13,10 @@ module Memo1
          where
  import System.Mem.StableName    ( StableName, makeStableName, hashStableName )
 -import System.Mem.Weak          ( Weak, mkWeakPtr, mkWeak, deRefWeak, finalize )
 +import System.Mem.Weak          ( Weak, mkWeak, deRefWeak, finalize )
  import Data.Array.IO            ( IOArray, newArray, readArray, writeArray )
  import System.IO.Unsafe         ( unsafePerformIO )
 -import Control.Concurrent.MVar  ( MVar, newMVar, putMVar, takeMVar )
 +import Control.Concurrent.MVar  ( MVar, newMVar, putMVar, takeMVar, mkWeakMVar )
  \end{code}
  -----------------------------------------------------------------------------
@@ -78,7 +78,7 @@ lazyMemoSized size f =
     let (table,weak) = unsafePerformIO (
                  do { tbl <- newArray (0,size) []
                     ; mvar <- newMVar (size,tbl)
 -                   ; weak <- mkWeakPtr mvar (Just (table_finalizer tbl size))
 +                   ; weak <- mkWeakMVar mvar (table_finalizer tbl size)
                     ; return (mvar,weak)
                     })
     in  memo' f table weak

libraries/base/tests/Memo2.lhs

@@ -13,10 +13,10 @@ module Memo2
          where
  import System.Mem.StableName    ( StableName, makeStableName, hashStableName )
 -import System.Mem.Weak          ( Weak, mkWeakPtr, mkWeak, deRefWeak, finalize )
 +import System.Mem.Weak          ( Weak, mkWeak, deRefWeak, finalize )
  import Data.Array.IO            ( IOArray, newArray, readArray, writeArray )
  import System.IO.Unsafe         ( unsafePerformIO )
 -import Control.Concurrent.MVar  ( MVar, newMVar, putMVar, takeMVar )
 +import Control.Concurrent.MVar  ( MVar, newMVar, putMVar, takeMVar, mkWeakMVar )
  \end{code}
  -----------------------------------------------------------------------------
@@ -78,7 +78,7 @@ lazyMemoSized size f =
     let (table,weak) = unsafePerformIO (
                  do { tbl <- newArray (0,size) []
                     ; mvar <- newMVar (size,tbl)
 -                   ; weak <- mkWeakPtr mvar (Just (table_finalizer tbl size))
 +                   ; weak <- mkWeakMVar mvar (table_finalizer tbl size)
                     ; return (mvar,weak)
                     })
     in  memo' f table weak

libraries/base/tests/all.T

@@ -135,8 +135,7 @@ test('list003', when(fast(), skip), compile_and_run, [''])
  test('isSuffixOf', normal, compile_and_run, [''])
  test('memo001', [extra_files(['Memo1.lhs']),
 -                 extra_run_opts('+RTS -A10k -RTS'),
 -                 expect_broken_for(27396, opt_ways)], multimod_compile_and_run,
 +                 extra_run_opts('+RTS -A10k -RTS')], multimod_compile_and_run,
       ['memo001', ''])
  test('memo002', [extra_files(['Memo2.lhs']),