Fix debug Hermes being embedded in iOS Release builds after hermes-engine pod re-install#57574
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Fix debug Hermes being embedded in iOS Release builds after hermes-engine pod re-install#57574tjzel wants to merge 2 commits into
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…gine pod re-install (#57574) Summary: The `hermes-engine` pod is always installed from the debug tarball; the debug/release selection is deferred to a build phase that runs `sdks/hermes-engine/utils/replace_hermes_version.js`. The script tracks which variant currently sits in `Pods/hermes-engine` through a `.last_build_configuration` marker at the Pods root and skips the swap when the marker matches the requested configuration. Whenever CocoaPods re-installs `hermes-engine`, the engine resets to the debug variant while the marker still claims `Release`. The next Release build takes the "Same config of the previous build" path and silently embeds the debug `hermesvm` into the Release app. I moved the marker inside `Pods/hermes-engine/` so a pod re-install destroys it together with the engine it describes and the next build re-runs the swap — the same pattern `replace-rncore-version.js` and `replace_dependencies_version.js` already use for their prebuilts. I also added some assertions. ## Changelog: [IOS] [FIXED] - Fix debug Hermes being silently embedded in Release builds after the hermes-engine pod is re-installed Pull Request resolved: #57574 Test Plan: Reproduced on `react-native@0.86.0` before the change: Release build, then `rm -rf ios/Pods/hermes-engine && pod install`, then Release build again — the app's embedded `hermesvm` is the debug binary (`nm -gU -arch arm64 hermesvm | grep -c CDPDebugAPI` prints 6, ~12.2 MB; the release binary prints 0, ~10.2 MB) while the marker says `Release`. Reviewed By: cortinico Differential Revision: D112308961 Pulled By: cipolleschi fbshipit-source-id: 2f4111ac7030fcedd888d91c6eb2dd034dc13c0d
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Summary:
The
hermes-enginepod is always installed from the debug tarball; the debug/release selection is deferred to a build phase that runssdks/hermes-engine/utils/replace_hermes_version.js. The script tracks which variant currently sits inPods/hermes-enginethrough a.last_build_configurationmarker at the Pods root and skips the swap when the marker matches the requested configuration.Whenever CocoaPods re-installs
hermes-engine, the engine resets to the debug variant while the marker still claimsRelease. The next Release build takes the "Same config of the previous build" path and silently embeds the debughermesvminto the Release app.I moved the marker inside
Pods/hermes-engine/so a pod re-install destroys it together with the engine it describes and the next build re-runs the swap — the same patternreplace-rncore-version.jsandreplace_dependencies_version.jsalready use for their prebuilts.I also added some assertions.
Changelog:
[IOS] [FIXED] - Fix debug Hermes being silently embedded in Release builds after the hermes-engine pod is re-installed
Test Plan:
Reproduced on
react-native@0.86.0before the change: Release build, thenrm -rf ios/Pods/hermes-engine && pod install, then Release build again — the app's embeddedhermesvmis the debug binary (nm -gU -arch arm64 hermesvm | grep -c CDPDebugAPIprints 6, ~12.2 MB; the release binary prints 0, ~10.2 MB) while the marker saysRelease.