diff --git a/compiler/rustc_codegen_ssa/src/back/archive.rs b/compiler/rustc_codegen_ssa/src/back/archive.rs index 280fa49e29b60..8274caa42bcfc 100644 --- a/compiler/rustc_codegen_ssa/src/back/archive.rs +++ b/compiler/rustc_codegen_ssa/src/back/archive.rs @@ -10,6 +10,7 @@ pub use ar_archive_writer::get_native_object_symbols; use ar_archive_writer::{write_archive_to_stream, ArchiveKind, NewArchiveMember}; use object::read::archive::ArchiveFile; use object::read::macho::FatArch; +use tempfile::Builder as TempFileBuilder; use std::error::Error; use std::fs::File; @@ -271,10 +272,27 @@ impl<'a> ArArchiveBuilder<'a> { }) } - let mut w = File::create(output) - .map_err(|err| io_error_context("failed to create archive file", err))?; - - write_archive_to_stream(&mut w, &entries, true, archive_kind, true, false)?; + // Write to a temporary file first before atomically renaming to the final name. + // This prevents programs (including rustc) from attempting to read a partial archive. + // It also enables writing an archive with the same filename as a dependency on Windows as + // required by a test. + let mut archive_tmpfile = TempFileBuilder::new() + .suffix(".temp-archive") + .tempfile_in(output.parent().unwrap_or_else(|| Path::new(""))) + .map_err(|err| io_error_context("couldn't create a temp file", err))?; + + write_archive_to_stream( + archive_tmpfile.as_file_mut(), + &entries, + true, + archive_kind, + true, + false, + )?; + + archive_tmpfile + .persist(output) + .map_err(|err| io_error_context("failed to rename archive file", err.error))?; Ok(!entries.is_empty()) }