Can use Hermes on a new project

[ospfranco]

Environment

react-native -v: 5.0.1
npm ls react-native-macos: 0.64.18
node -v: 16.12.0
npm -v: 8.1.0
yarn --version: 1.22.17
xcodebuild -version: 13.1

Steps to reproduce the bug

I created a new RN macOS project the other day, I wanted to start right away with Hermes, I followed the installation instructions and I got to the following issue:

https://stackoverflow.com/questions/68497865/rct-folly-error-when-using-hermes-with-ios

Debugging it is very confusing since all the info online points to flipper on iOS, but on macOS there is no flipper... anyways, I tried updating a bunch of things and had to resort to a similar solution to the one on the stack overflow answer on my Podfile:

require_relative '../node_modules/react-native-macos/scripts/react_native_pods'
require_relative '../node_modules/@react-native-community/cli-platform-ios/native_modules'

# fixes for last Mac updates
def find_and_replace(dir, findstr, replacestr)
  Dir[dir].each do |name|
      text = File.read(name)
      replace = text.gsub(findstr,replacestr)
      if text != replace
          puts "Fix: " + name
          File.open(name, "w") { |file| file.puts replace }
          STDOUT.flush
      end
  end
  Dir[dir + '*/'].each(&method(:find_and_replace))
end

target 'messer-macOS' do
  platform :macos, '10.14'
  use_native_modules!
  use_react_native!(
    :path => '../node_modules/react-native-macos',
    :hermes_enabled => true
  )
  
  
  post_install do |installer|
    find_and_replace("Pods/Headers/Private/RCT-Folly/folly/synchronization/DistributedMutex-inl.h",
    "atomic_notify_one(state)", "folly::atomic_notify_one(state)")
  end
end

is there any plan to fix this (AFAIK RCT-Folly already fixed this in some of the later versions?)

Expected Behavior

No response

Actual Behavior

No response

Reproducible Demo

No response

Additional context

No response

[HeyImChris]

Duplicate of #952

[Saadnajmi]

@kelset the post install phase replacing ayomic_notify_one might be of interest to you here

[ospfranco]

Just FYI I just trying updating a project to rn-macos 0.66.2 and this is still happening (although I think in a different file), so this issue is not solved, I still cannot use hermes on a new project

[ospfranco]

Ah, it seems it is not related to hermes, I just tried updating to rn-macos 0.66 and it's not working. I'll create a new issue later

[Saadnajmi]

@ospfranco I think you need this in your podfile:

https://github.com/microsoft/react-native-macos/blob/main/packages/rn-tester/Podfile#L100-L102

[ospfranco]

@Saadnajmi thanks a lot, that error is gone, but now I'm getting arm64 compilation errors, some people seem to have solved this by compiling the app in Rosetta mode?

facebook#29605

[Saadnajmi]

@ospfranco I run into that intermittently and haven't found a cause. I suspect it might be an xcode incremental build problem. One thing to try is to do a full clean (cmd+shift+k) in xcode before building.

[ospfranco]

Already tried that, also deleting the derived data folder, still no luck :(

[ospfranco]

I initialized a brand new project and there it seems to be working

[ospfranco]

I managed to get it working after resetting a bunch of swift flags in the Build Settings with a brand new rn-macos project, some of my changes:

• Reset Swift Compiler custom flags
• Reset Dead code stripping to NO
• Reset Framework search paths
• Reset Library search paths
• Reset embed swift libraries to NO