fatal error: 'boost/preprocessor/control/expr_iif.hpp' file not found

Question

I have a React Native project. I recently updated to macOS Big Sur 11.3 and XCode Version 12.5 (12E262).

When I build the project in XCode I get the following error:

../ios/Pods/Headers/Public/Flipper-Folly/folly/functional/Invoke.h:22:10: fatal error: 'boost/preprocessor/control/expr_iif.hpp' file not found
#include <boost/preprocessor/control/expr_iif.hpp>
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.

When I browse to Pods folder, expr_iif.hpp file exists.

I tried removing Pods folder, Podfile.lock, .xcworkspace. Deleted npm cache. Then ran pod install.

But no luck.

This build-time error is thrown by Flipper-RSocket and Flipper-Folly.

I can provide further details if requested.

Answer 1

I just had this issue and it happens when you have incompatible versions of Flipper pods.

This worked for me:

1. Update your Podfile to install Flipper like this:

use_flipper!({ 'Flipper' => '0.93.0', 'Flipper-Folly' => '2.6.7', 'Flipper-DoubleConversion' => '3.1.7' })

2. Update deployment target on both Podfile and Xcode project o 12.1 or newer:

platform :ios, '12.1'

3. Remove Podfile.lock
4. pod install --repo-update
5. Close and re-open the Xcode project

You may also try fixing permissions if the above is not enough for you:

chmod -R 755 ios/Pods/boost-for-react-native

The error went away after this.

Answer 2

It completely removes Flipper, but here's a workaround I used

• disabled Flipper in PodFile (as explained in an answer here: React Native Project is not running on iOS Simulator)
• deleted Pods directory
• re-ran npx pod-install
• started the application (npx react-native run-ios)