fix: use -fmodule-map-file for Swift metadata discovery in nsld.sh#374
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Replace HEADER_SEARCH_PATHS-based module discovery with explicit -fmodule-map-file= for the nsswiftsupport modulemap. The directory-based discovery via -I was unreliable — the metadata generator's clang would sometimes fail to find the modulemap, or during parallel multi-arch builds, discover modulemaps from both architectures through the parent internal/ directory (which is also in HEADER_SEARCH_PATHS), causing "redefinition of module 'nsswiftsupport'" errors and potentially using a stale bridging header from the wrong architecture. This resulted in intermittent "ReferenceError: <class> is not defined" errors for Swift plugin classes after npm install, requiring a full platforms/ delete to recover.
NathanWalker
approved these changes
May 17, 2026
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Replace HEADER_SEARCH_PATHS-based module discovery with explicit -fmodule-map-file= for the nsswiftsupport modulemap. The directory-based discovery via -I was unreliable — the metadata generator's clang would sometimes fail to find the modulemap, or during parallel multi-arch builds, discover modulemaps from both architectures through the parent internal/ directory (which is also in HEADER_SEARCH_PATHS), causing "redefinition of module 'nsswiftsupport'" errors and potentially using a stale bridging header from the wrong architecture.
This resulted in intermittent "ReferenceError: is not defined" errors for Swift plugin classes after npm install, requiring a full platforms/ delete to recover.