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C wrappers for Haskell foreign exports don't have finalizers (causes memory leak).

For each foreign export RTS creates a static C wrapper, which is initialized on DLL_PROCESS_ATTACH, but it has no finalizer/destructor to be called during DLL_PROCESS_DETACH. So it will stay alive till the program termination. That's why if one uses a Haskell DLL in their C/C++ project, **consumed memory is not fully released after freeing the library**. [[br]][[br]] There are four files attached to this ticket.

  • **HaskellExports.hs** contains exact one foreign export function;
  • **CWrapper.cpp** is supposed to contain wrappers to the Haskell functions, described in HaskellExports.hs, but it doesn't because they make no difference;
  • **main.cpp**: here in an endless loop the DLL (built with the help of the script below) is loaded and freed at once. Launched program is crashed in a while (because it runs out of memory);
  • **build.sh** is a script for building the library.

[[br]] The main program was built with MSVC 2015.

Trac metadata
Trac field Value
Version 8.0.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler (FFI)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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