Segfault using TemplateHaskell (NixOs, MacOs for now)

[fiadliel]

In a simple project with polysemy included, the addition of the makeSem call into Template Haskell causes HLS to crash reliably (segmentation fault). With the makeSem line commented out, the plugin starts correctly.

e.g.

{-# LANGUAGE TemplateHaskell #-}

module Main where

import Polysemy
import Polysemy.Reader

data MyEffect m a where
  Test :: m a -> MyEffect m a

makeSem ''MyEffect

A repository that should demonstrate the issue is at https://github.com/fiadliel/effects

[lukel97]

I can't reproduce this with HLS built from source on mac, going to try with the 0.2.2 binary

[lukel97]

I can't reproduce it with the 0.2.2 binary either, with this file:

{-# LANGUAGE DataKinds #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE GADTs #-}
{-# LANGUAGE TemplateHaskell #-}

module Main where

import Polysemy
import Polysemy.Reader

data MyEffect m a where
  Test :: m a -> MyEffect m a

makeSem ''MyEffect

and with polysemy-1.3.0.0 on ghc-8.10.1. What version of GHC are you using? Can you pass on any of the logs too?

[fiadliel]

This is ghc 8.4.4 (from a haskell.nix setup). There was a previous bug about Template Haskell incompatibilities at input-output-hk/haskell.nix#400 but that's been fixed for a while.

If you have nix installed, you should be able to create the environment with nix-shell. You would probably want to use the cachix cache earnestresearch-public.cachix.org (unless you like compiling a lot).

I can also look at getting something from lldb, though it's been a while (and different language) ago 😅

If the answer is that haskell-language-server doesn't support this use case, it's not too bad as long as ghcide continues to work (this is the extant working system that we can fall back to); in this case, ghcide is compiled against the nix environment's ghc.

---

Basic info from lldb (not knowing what I'm doing):

(lldb) cont
Process 15466 resuming
Process 15466 stopped
* thread #27, stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
    frame #0: 0x0000000110da766f
->  0x110da766f: movq   0x5(%rbx), %rbx
    0x110da7673: movq   %rbx, %rcx
    0x110da7676: movq   %rax, %rbx
    0x110da7679: movq   %rcx, 0x8(%rbp)
Target 0: (haskell-language-server-macOS-8.8.4) stopped.
(lldb) bt
* thread #27, stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
  * frame #0: 0x0000000110da766f
    frame #1: 0x61000000000012cf

---

Log messages:

❯ ~/Downloads/haskell-language-server-macOS-8.8.4 --debug
haskell-language-server version: 0.2.1.0 (GHC: 8.8.4) (PATH: /Users/gcoady/Downloads/haskell-language-server-macOS-8.8.4) (GIT hash: a6f4aba69e45dfb48bc5721537fef120971d3899)
(haskell-language-server)Ghcide setup tester in /Users/gcoady/src/github.com/fiadliel/effects.
Report bugs at https://github.com/haskell/haskell-language-server/issues

Step 1/4: Finding files to test in /Users/gcoady/src/github.com/fiadliel/effects
Found 2 files

Step 2/4: Looking for hie.yaml files that control setup
Found 1 cradle

Step 3/4: Initializing the IDE

Step 4/4: Type checking the files
[INFO] Consulting the cradle for "/Users/gcoady/src/github.com/fiadliel/effects/Setup.hs"
Output from setting up the cradle Cradle {cradleRootDir = "/Users/gcoady/src/github.com/fiadliel/effects", cradleOptsProg = CradleAction: Cabal}
> cabal: Unknown target
> '/Users/gcoady/src/github.com/fiadliel/effects/Setup.hs'.
> The package servant-with-effects has no file target 'Setup.hs'.
>
>
File:     /Users/gcoady/src/github.com/fiadliel/effects/Setup.hs
Hidden:   no
Range:    1:0-2:0
Source:   cradle
Severity: DsError
Message:
  Failed to parse result of calling cabal

  cabal: Unknown target
  '/Users/gcoady/src/github.com/fiadliel/effects/Setup.hs'.
  The package servant-with-effects has no file target 'Setup.hs'.




[INFO] Consulting the cradle for "/Users/gcoady/src/github.com/fiadliel/effects/src/Main.hs"
Output from setting up the cradle Cradle {cradleRootDir = "/Users/gcoady/src/github.com/fiadliel/effects", cradleOptsProg = CradleAction: Cabal}
> Warning: No remote package servers have been specified. Usually you would have
> one specified in the config file.
> Resolving dependencies...
> Build profile: -w ghc-8.8.4 -O1
> In order, the following will be built (use -v for more details):
>  - servant-with-effects-0.1.0.0 (exe:servant-with-effects) (configuration changed)
> Configuring executable 'servant-with-effects' for servant-with-effects-0.1.0.0..
> Warning: The 'license-file' field refers to the file 'LICENSE' which does not
> exist.
> Preprocessing executable 'servant-with-effects' for servant-with-effects-0.1.0.0..
[INFO] Using interface files cache dir: /Users/gcoady/.cache/ghcide/main-1c5eedb9d24916147b5cef09d100a08962c59f40
[INFO] Making new HscEnv[main]
[INFO] Consulting the cradle for "/Users/gcoady/src/github.com/fiadliel/effects/Setup.hs"
Output from setting up the cradle Cradle {cradleRootDir = "/Users/gcoady/src/github.com/fiadliel/effects", cradleOptsProg = CradleAction: Cabal}
> cabal: Unknown target
> '/Users/gcoady/src/github.com/fiadliel/effects/Setup.hs'.
> The package servant-with-effects has no file target 'Setup.hs'.
>
>
zsh: segmentation fault  ~/Downloads/haskell-language-server-macOS-8.8.4 --debug

[fiadliel]

And tried with 0.2.2, same error; version is:

haskell-language-server version: 0.2.2.0 (GHC: 8.8.4) (PATH: /Users/gcoady/Downloads/haskell-language-server-macOS-8.8.4-1) (GIT hash: e44f618c11b7978264a94beeee00d1f014867f6d)

[lukel97]

Hm those logs don't look good, not sure why its setting up a cradle multiple times for the same file. I've never used nix before but I think its about time I install it to see what's going on...

[lukel97]

I just noticed your nix expression ends up downloading ghc 8.4.4 but your cabal constraints suggest ghc 8.8.4 This was to bootstrap 8.8.4 =

[lukel97]

Took a while to build without the caches, but I can recreate it now. Time to figure out what's going on

[Galagora]

I'm also facing the same problem on NixOS, using HLS 0.3.0.0 with GHC 8.8.3 (and 8.8.4). The source file is the same (hello world with makeSem).

logs

$ haskell-language-server 
haskell-language-server version: 0.3.0.0 (GHC: 8.8.3) (PATH: /nix/store/zly7m0p5sd0iv8qn1n97gxkx4lkbh00z-haskell-language-server-0.3.0.0/bin/haskell-language-server)
(haskell-language-server)Ghcide setup tester in /home/ao/code/haskell-starter.
Report bugs at https://github.com/haskell/haskell-language-server/issues

Tool versions found on the $PATH
cabal:		3.2.0.0
stack:		Not found
ghc:		8.8.3


Step 1/4: Finding files to test in /home/ao/code/haskell-starter
Found 1 files

Step 2/4: Looking for hie.yaml files that control setup
Found 1 cradle

Step 3/4: Initializing the IDE

Step 4/4: Type checking the files
[INFO] Consulting the cradle for "/home/ao/code/haskell-starter/src/Main.hs"
Output from setting up the cradle Cradle {cradleRootDir = "/home/ao/code/haskell-starter", cradleOptsProg = CradleAction: Cabal}
> Warning: No remote package servers have been specified. Usually you would have
> one specified in the config file.
> Resolving dependencies...
> Build profile: -w ghc-8.8.3 -O1
> In order, the following will be built (use -v for more details):
>  - starter-0.1.0.0 (exe:starter) (configuration changed)
> Configuring executable 'starter' for starter-0.1.0.0..
> Preprocessing executable 'starter' for starter-0.1.0.0..
[INFO] Using interface files cache dir: /home/ao/.cache/ghcide/main-97733fd591cce96508bbfeab608cd02ca28697c1
[INFO] Making new HscEnv[main]
[1]    11008 segmentation fault (core dumped)  haskell-language-server

[Galagora]

Same issue when using freer-simple's makeEffect (equivalent to makeSem) and motor's reflectEvents, both Template Haskell functions. Does HLS not support TH or is this merely a bug in the implementation?