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The prebuild stages headers into .build/headers as hard links, and skipped any target that already existed. A hard link shares an inode, so in-place edits propagate, but git checkout renames a new file over the source and gives it a new inode. The staged link then serves the old contents forever and setup never repairs it, so the build compiles against headers from whichever commit was checked out when the link was first created. The staging function now compares the staged file against its source and relinks it when the inodes differ. Targets a pass has already claimed are left alone, so sources that flatten onto the same target keep resolving to the first one visited, as before. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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@shwanton has imported this pull request. If you are a Meta employee, you can view this in D120740409. |
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Summary: The iOS prebuild (`node scripts/ios-prebuild`) stages React Native's headers into `packages/react-native/.build/headers` as hard links, and skipped any target that already existed. When changing the original source files, these hard links can become stale and errors like this can occur: ``` Libraries/LinkingIOS/RCTLinkingManager.mm:91:7: error: use of undeclared identifier 'RCTIsSceneDelegateApp' ``` This is a problem that contributors will see - not regular users, but the fix helps with strange error messages. ## Changelog: [INTERNAL] [FIXED] - Repair stale staged headers in the iOS prebuild instead of compiling against a previous checkout's copies Pull Request resolved: #58596 Test Plan: ✅ New unit tests, 16 cases in `packages/react-native/scripts/ios-prebuild/__tests__/setup-test.js`, using real temporary directories rather than an `fs` mock, since the defect is about inodes. End to end on an Xcode 27 checkout: - Replaced a staged header with a copy, so it kept the same contents but a different inode. `node scripts/ios-prebuild -s -f Debug` restored it to the source inode and logged `Linked React/Base → .build/headers/React`. The previous code skipped it. - Ran setup a second time with nothing changed: no file was relinked, and nothing was logged. - Confirmed the three colliding targets still resolve to the same source as before the change, by inode. - `node scripts/ios-prebuild -b -f Debug -p ios-simulator` → `** BUILD SUCCEEDED **`. Reviewed By: cipolleschi Differential Revision: D120740409 Pulled By: shwanton fbshipit-source-id: 41c1eb112c3395d6c7158d7151be7fdd92a21cef (cherry picked from commit b935e74)
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Summary:
The iOS prebuild (
node scripts/ios-prebuild) stages React Native's headers intopackages/react-native/.build/headersas hard links, and skipped any target that already existed.When changing the original source files, these hard links can become stale and errors like this can occur:
This is a problem that contributors will see - not regular users, but the fix helps with strange error messages.
Changelog:
[INTERNAL] [FIXED] - Repair stale staged headers in the iOS prebuild instead of compiling against a previous checkout's copies
Test Plan:
✅ New unit tests, 16 cases in
packages/react-native/scripts/ios-prebuild/__tests__/setup-test.js, using real temporary directories rather than anfsmock, since the defect is about inodes.End to end on an Xcode 27 checkout:
node scripts/ios-prebuild -s -f Debugrestored it to the source inode and loggedLinked React/Base → .build/headers/React. The previous code skipped it.node scripts/ios-prebuild -b -f Debug -p ios-simulator→** BUILD SUCCEEDED **.