Compiler segfaults on lambda sugar (nim 1.6.16)

[mynameisdaniil]

Description

I've been trying to use some functional style programming to access type lifted into Option.

import sugar

p.localNode.address.map((a) => $a.port).get("0")
# where
address: Option[Address]

type Address* = object
  ip*: ValidIpAddress
  port*: Port

If you re-arrange this code differently i.e. move map((a) => $a.port).get("0") part into separate proc this issue goes away. Which makes me think it is somehow connected to type inference.

To replicate this:

git clone https://github.com/status-im/nimbus-eth1.git
cd nimbus-eth1
git checkout compiler-segfault
# Optional, select version of nim compiler to compile with
# This one for 1.6.16
export NIM_COMMIT=3c9b68dc157804885b14a1984efc25e8b7cc861d

source env.sh
make fluffy -j4

Nim Version

Nim Compiler Version 1.6.16 [MacOSX: arm64]
Compiled at 2023-10-12
Copyright (c) 2006-2023 by Andreas Rumpf

git hash: 3c9b68d
active boot switches: -d:release

Current Output

SIGSEGV: Illegal storage access. (Attempt to read from nil?)
<...>/nimbus-eth1/vendor/nimbus-build-system/scripts/env.sh: line 85: 81689 Segmentation fault: 11  "$@"

Expected Output

No response

Possible Solution

No response

Additional Information

No response

[juancarlospaco]

Can you provide a reduced assertive source code repro sample ?.

[mynameisdaniil]

@juancarlospaco Sorry, I was trying to make minimal working example, but was unable to. But I can assist you with the codebase where this bug is reproducible.

[tersec]

Repro:

protocol.nim:

{.push raises: [].}

import
  "."/[node]

import
  std/[options, sugar]

var closestNodes: seq[Node]
for cn in closestNodes:
  discard cn.address.map(a => a.port)

node.nim

import std/options

type
  Address* = object
    port*: int

  Node* = ref object
    address*: Option[Address]

On 1.6 (any version I tried, up to current version-1-6 from branch):

SIGSEGV: Illegal storage access. (Attempt to read from nil?)
Segmentation fault (core dumped)

2.0 and devel don't seem to have this problem.

Example Nim versions:

SIGSEGV upon compilation:

Nim Compiler Version 1.6.21 [Linux: amd64]
Compiled at 2024-05-27
Copyright (c) 2006-2023 by Andreas Rumpf

git hash: 38640664088251bbc88917b4bacfd86ec53014b8
active boot switches: -d:release

No SIGSEGV:

Nim Compiler Version 2.0.5 [Linux: amd64]
Compiled at 2024-05-27
Copyright (c) 2006-2023 by Andreas Rumpf

git hash: ab053fd56a6517531441cdbf0be5536189831c9c
active boot switches: -d:release

Nim Compiler Version 2.1.1 [Linux: amd64]
Compiled at 2024-05-27
Copyright (c) 2006-2024 by Andreas Rumpf

git hash: daad06bd07ff11cc2b0c74b604ff82899e923d59
active boot switches: -d:release