| commit | a28b54033227d930672ec7f2714de52e5e0a67eb | [log] [tgz] |
|---|---|---|
| author | Ulf Adams <ulfjack@google.com> | Fri Feb 24 09:28:44 2017 +0000 |
| committer | Irina Iancu <elenairina@google.com> | Fri Feb 24 15:13:44 2017 +0000 |
| tree | 8bb930f832015d9f23c5f5f8a11a16cd34ab6d32 | |
| parent | e50388e66e1378b8c6a93bbc331e27771bd3aedc [diff] |
Fix Cpp action caching This combines both previous changes and extends them to work both with and without kchodorow@'s rollout of the exec root rearrangement. Unfortunately, each of these changes individually breaks something somewhere, so they must all go into a single commit. Change 1: CppCompileAction must return false from inputsKnown for .d pruning This is necessary (but not sufficient) for the action cache to work correctly. Consider the following sequence of events: 1. action is executed 2. .d pruning is performed 3. action cache writes entry with post-pruning inputs list 4. action gets regenerated (e.g., due to server restart) 5. the action cache calls inputsKnown(), which returns true 6. action cache checks entry from step 3 against pre-pruning inputs list, which results in a cache miss The action cache needs to know that the current list is not the final list, so inputsKnown() in step 5 must return false if .d pruning is enabled. Change 2: Fix artifact root discovery for external artifacts The SkyframeExecutor was assuming that all exec paths were coming from the main repository. Instead, rely on external exec paths to start with "../". Additional change 3: In addition, update the PackageRootResolverWithEnvironment and the HeaderDiscovery to use the single unified repository name guessing implementation. Previously, the PackageRootResolverWithEnvironment was poisoning the source artifact cache, which then caused subsequent lookups to return a bad artifact. Add a precondition to double-check that artifacts looked up by exec path have the correct source root. For compatibility with kchodorow@'s upcoming exec root refactor, if the exec path starts with "external", then assume it's coming from an external repository. This must be removed when that change is successfully rolled out, or it will break if anyone creates a package called 'external'. Additional change 4: On top of all of that, PackageRootResolverWithEnvironment and SkyframeExecutor must use the same source root computation as the Package class itself. I extracted the corresponding code to Root, and added comments both there and in Package to clearly indicate that these methods have to always be modified in sync. Fixes #2490. -- PiperOrigin-RevId: 148439309 MOS_MIGRATED_REVID=148439309
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