llvm-project

0387a86f - [clang][modules] Fix use-after-free in header serialization (#96356)

[clang][modules] Fix use-after-free in header serialization (#96356) With the pruning of unused module map files disabled (`-fno-modules-prune-non-affecting-module-map-files`), `HeaderFileInfo` no longer gets deserialized before `ASTWriter::WriteHeaderSearch()`. This function then interleaves the stores of references to `KnownHeader` with their lazy deserialization. Lazy deserialization may cause reallocation of `ModuleMap::Headers` entries (including its `SmallVector<KnownHeader, 1>` values) thus making previously-stored `ArrayRef<KnownHeader>` dangling. This patch fixes that situation by storing a copy instead.