Heap limit Allocation failed/JavascriptHeap out of memory

When using hardhat to compile contracts/generate typescript, after the compilation finishes successfully typechain hangs for several seconds before running out of memory.

The most recent addition to the code were some nested Structs (no more than 2 levels), though I’ve never run into any issues like this before, and definitely no recursive structs.

reinstalling (purging node_modules) did not change the result.

Compilation finished successfully
Creating Typechain artifacts in directory typechain for target ethers-v5

<--- Last few GCs --->

[3314:0x7fe0d0008000]    43338 ms: Mark-sweep 4056.1 (4134.2) -> 4052.1 (4134.2) MB, 3081.8 / 0.0 ms  (average mu = 0.184, current mu = 0.041) allocation failure scavenge might not succeed
[3314:0x7fe0d0008000]    47172 ms: Mark-sweep 4068.0 (4134.4) -> 4063.9 (4159.1) MB, 3795.3 / 0.0 ms  (average mu = 0.092, current mu = 0.010) allocation failure scavenge might not succeed


<--- JS stacktrace --->

FATAL ERROR: Reached heap limit Allocation failed - JavaScript heap out of memory
 1: 0x1100c4515 node::Abort() (.cold.1) [/usr/local/bin/node]
 2: 0x10edc5989 node::Abort() [/usr/local/bin/node]
 3: 0x10edc5aff node::OnFatalError(char const*, char const*) [/usr/local/bin/node]
 4: 0x10ef452c7 v8::Utils::ReportOOMFailure(v8::internal::Isolate*, char const*, bool) [/usr/local/bin/node]
 5: 0x10ef45263 v8::internal::V8::FatalProcessOutOfMemory(v8::internal::Isolate*, char const*, bool) [/usr/local/bin/node]
 6: 0x10f0e6975 v8::internal::Heap::FatalProcessOutOfMemory(char const*) [/usr/local/bin/node]
 7: 0x10f0e52fc v8::internal::Heap::CollectGarbage(v8::internal::AllocationSpace, v8::internal::GarbageCollectionReason, v8::GCCallbackFlags) [/usr/local/bin/node]
 8: 0x10f0f1af0 v8::internal::Heap::AllocateRawWithLightRetrySlowPath(int, v8::internal::AllocationType, v8::internal::AllocationOrigin, v8::internal::AllocationAlignment) [/usr/local/bin/node]
 9: 0x10f0f1b71 v8::internal::Heap::AllocateRawWithRetryOrFailSlowPath(int, v8::internal::AllocationType, v8::internal::AllocationOrigin, v8::internal::AllocationAlignment) [/usr/local/bin/node]
10: 0x10f0becc7 v8::internal::Factory::NewFillerObject(int, bool, v8::internal::AllocationType, v8::internal::AllocationOrigin) [/usr/local/bin/node]
11: 0x10f47449e v8::internal::Runtime_AllocateInYoungGeneration(int, unsigned long*, v8::internal::Isolate*) [/usr/local/bin/node]
12: 0x10f81ddd9 Builtins_CEntry_Return1_DontSaveFPRegs_ArgvOnStack_NoBuiltinExit [/usr/local/bin/node]
error Command failed with signal "SIGABRT".
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

[krzkaczor]

@DominicRomanowski thank you! This is a great repro. It will be fixed this week 😃

[0xdomrom]

pragma solidity 0.7.6;
pragma experimental ABIEncoderV2;


library Observer {

  struct Observation {
    int val;
    uint blockTimestamp;
  }

  function write(
    Observation[65535] storage self,
    uint16 index,
    uint newVal,
    uint blockTimestamp
  ) internal returns (uint16 indexUpdated) { }
}



contract TestTypechain {
  using Observer for Observer.Observation[65535];

  struct ObservationParams {
    Observer.Observation[65535] observations;
    uint16 index;
  }

  struct Bar {
    ObservationParams fooObservations;
  }

  mapping(uint => Bar) public bars;

  function makeObservation(uint barId, uint newVal) external {
    Bar storage bar = bars[barId];
    bar.fooObservations.index = bar.fooObservations.observations.write(bar.fooObservations.index, newVal, block.timestamp);
  }
}

Heya, I was able to isolate the issue; Removing the size limit (65535) on the array allowed the typechain to compile