Building with Hermes Enabled for iOS on RN 0.64.2 Hangs

[vcellu]

Description

Building in release mode, with Hermes enabled in iOS in XCODE 12.5 hangs Xcode

React Native version:

System:
OS: macOS 11.3
CPU: (16) x64 Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz
Memory: 2.57 GB / 32.00 GB
Shell: 5.8 - /bin/zsh
Binaries:
Node: 14.15.5 - /usr/local/bin/node
Yarn: 1.22.10 - /usr/local/bin/yarn
npm: 6.14.11 - /usr/local/bin/npm
Watchman: 2021.05.31.00 - /usr/local/bin/watchman
Managers:
CocoaPods: 1.10.1 - /Users/vel/.rvm/gems/ruby-2.6.6/bin/pod
SDKs:
iOS SDK:
Platforms: iOS 14.5, DriverKit 20.4, macOS 11.3, tvOS 14.5, watchOS 7.4
Android SDK:
API Levels: 28, 29, 30
Build Tools: 28.0.3, 29.0.2, 30.0.3
System Images: android-29 | Intel x86 Atom_64, android-29 | Google APIs Intel x86 Atom_64, android-30 | Google APIs Intel x86 Atom_64, android-S | Google APIs ARM 64 v8a, android-S | Google APIs Intel x86 Atom_64
Android NDK: Not Found
IDEs:
Android Studio: 4.1 AI-201.8743.12.41.7199119
Xcode: 12.5/12E262 - /usr/bin/xcodebuild
Languages:
Java: 1.8.0_242-release - /usr/bin/javac
npmPackages:
@react-native-community/cli: Not Found
react: 17.0.1 => 17.0.1
react-native: 0.64.2 => 0.64.2
react-native-macos: Not Found
npmGlobalPackages:
react-native: Not Found

Steps To Reproduce

Provide a detailed list of steps that reproduce the issue.

1. run npx react-native init SomeProject
2. enable hermes in podfile
3. rm -rf node_modules
4. rm -rf ios/pods
5. yarn
6. cd ios
7. pod install
8. open Xcode workspace
9. change scheme to build in release mode with debug executable off

Result:
There is a bunch of "The variable 'XXX' was not declared in anonymous function" messages and Xcode hangs and never completes. I have to Force Quit Xcode

Expected Results

I expect the project to build and run

Snack, code example, screenshot, or link to a repository:

Just run npx react-native init WhatEver

[mmehmetAliIzci]

Might be related to #31480

[vcellu]

Might be related to #31480

Hello, thanks for the reply. However, this is not the same issue. The issue referenced fails to link. In this issue it actually builds and links and it is successful if Hermes is not enabled in iOS.

[jeffbonasso-ambifi]

Same issue for me. We have a very large project so most likely running out of memory. I tried one workaround trying to increase memory putting this in Build Phases->Bundle React Native code and images, and still hanging.

export NODE_BINARY=node
export NODE_ARGS="--max_old_space_size=8192"
../node_modules/react-native/scripts/react-native-xcode.sh

Anyone know other workarounds?

[vcellu]

this seems to have been fixed in latest 0.65.1 release.