Auto merge of #97485 - bjorn3:new_archive_writer, r=wesleywiser

Rewrite LLVM's archive writer in Rust

This allows it to be used by other codegen backends.

Fixes https://github.com/bjorn3/rustc_codegen_cranelift/issues/1155

4 files changed, 8 insertions, 203 deletions

diff --git a/compiler/rustc_codegen_gcc/Cargo.lock b/compiler/rustc_codegen_gcc/Cargo.lock
index 6df2102470f..1cb219e12e0 100644
--- a/compiler/rustc_codegen_gcc/Cargo.lock
+++ b/compiler/rustc_codegen_gcc/Cargo.lock
@@ -12,12 +12,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "ar"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "450575f58f7bee32816abbff470cbc47797397c2a81e0eaced4b98436daf52e1"
-
-[[package]]
 name = "bitflags"
 version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -212,10 +206,8 @@ dependencies = [
 name = "rustc_codegen_gcc"
 version = "0.1.0"
 dependencies = [
- "ar",
  "gccjit",
  "lang_tester",
- "target-lexicon",
  "tempfile",
 ]
 
@@ -229,12 +221,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "target-lexicon"
-version = "0.10.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ab0e7238dcc7b40a7be719a25365910f6807bd864f4cce6b2e6b873658e2b19d"
-
-[[package]]
 name = "tempfile"
 version = "3.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/compiler/rustc_codegen_gcc/Cargo.toml b/compiler/rustc_codegen_gcc/Cargo.toml
index 211d19a8dc8..1f3da2f799b 100644
--- a/compiler/rustc_codegen_gcc/Cargo.toml
+++ b/compiler/rustc_codegen_gcc/Cargo.toml
@@ -27,10 +27,6 @@ gccjit = { git = "https://github.com/antoyo/gccjit.rs" }
 # Local copy.
 #gccjit = { path = "../gccjit.rs" }
 
-target-lexicon = "0.10.0"
-
-ar = "0.8.0"
-
 [dev-dependencies]
 lang_tester = "0.3.9"
 tempfile = "3.1.0"
diff --git a/compiler/rustc_codegen_gcc/src/archive.rs b/compiler/rustc_codegen_gcc/src/archive.rs
index f18ae7ea5e9..11fa074f5ac 100644
--- a/compiler/rustc_codegen_gcc/src/archive.rs
+++ b/compiler/rustc_codegen_gcc/src/archive.rs
@@ -1,44 +1,17 @@
-use std::fs::File;
 use std::path::{Path, PathBuf};
 
-use crate::errors::RanlibFailure;
-
-use rustc_codegen_ssa::back::archive::{ArchiveBuilder, ArchiveBuilderBuilder};
+use rustc_codegen_ssa::back::archive::{
+    get_native_object_symbols, ArArchiveBuilder, ArchiveBuilder, ArchiveBuilderBuilder,
+};
 use rustc_session::Session;
 
 use rustc_session::cstore::DllImport;
 
-struct ArchiveConfig<'a> {
-    sess: &'a Session,
-    use_native_ar: bool,
-    use_gnu_style_archive: bool,
-}
-
-#[derive(Debug)]
-enum ArchiveEntry {
-    FromArchive {
-        archive_index: usize,
-        entry_index: usize,
-    },
-    File(PathBuf),
-}
-
-pub struct ArArchiveBuilderBuilder;
+pub(crate) struct ArArchiveBuilderBuilder;
 
 impl ArchiveBuilderBuilder for ArArchiveBuilderBuilder {
     fn new_archive_builder<'a>(&self, sess: &'a Session) -> Box<dyn ArchiveBuilder<'a> + 'a> {
-        let config = ArchiveConfig {
-            sess,
-            use_native_ar: false,
-            // FIXME test for linux and System V derivatives instead
-            use_gnu_style_archive: sess.target.options.archive_format == "gnu",
-        };
-
-        Box::new(ArArchiveBuilder {
-            config,
-            src_archives: vec![],
-            entries: vec![],
-        })
+        Box::new(ArArchiveBuilder::new(sess, get_native_object_symbols))
     }
 
     fn create_dll_import_lib(
@@ -49,144 +22,6 @@ impl ArchiveBuilderBuilder for ArArchiveBuilderBuilder {
         _tmpdir: &Path,
         _is_direct_dependency: bool,
     ) -> PathBuf {
-        unimplemented!();
-    }
-}
-
-pub struct ArArchiveBuilder<'a> {
-    config: ArchiveConfig<'a>,
-    src_archives: Vec<(PathBuf, ar::Archive<File>)>,
-    // Don't use `HashMap` here, as the order is important. `rust.metadata.bin` must always be at
-    // the end of an archive for linkers to not get confused.
-    entries: Vec<(String, ArchiveEntry)>,
-}
-
-impl<'a> ArchiveBuilder<'a> for ArArchiveBuilder<'a> {
-    fn add_file(&mut self, file: &Path) {
-        self.entries.push((
-            file.file_name().unwrap().to_str().unwrap().to_string(),
-            ArchiveEntry::File(file.to_owned()),
-        ));
-    }
-
-    fn add_archive(
-        &mut self,
-        archive_path: &Path,
-        mut skip: Box<dyn FnMut(&str) -> bool + 'static>,
-    ) -> std::io::Result<()> {
-        let mut archive = ar::Archive::new(std::fs::File::open(&archive_path)?);
-        let archive_index = self.src_archives.len();
-
-        let mut i = 0;
-        while let Some(entry) = archive.next_entry() {
-            let entry = entry?;
-            let file_name = String::from_utf8(entry.header().identifier().to_vec())
-                .map_err(|err| std::io::Error::new(std::io::ErrorKind::InvalidData, err))?;
-            if !skip(&file_name) {
-                self.entries
-                    .push((file_name, ArchiveEntry::FromArchive { archive_index, entry_index: i }));
-            }
-            i += 1;
-        }
-
-        self.src_archives.push((archive_path.to_owned(), archive));
-        Ok(())
-    }
-
-    fn build(mut self: Box<Self>, output: &Path) -> bool {
-        use std::process::Command;
-
-        fn add_file_using_ar(archive: &Path, file: &Path) {
-            Command::new("ar")
-                .arg("r") // add or replace file
-                .arg("-c") // silence created file message
-                .arg(archive)
-                .arg(&file)
-                .status()
-                .unwrap();
-        }
-
-        enum BuilderKind<'a> {
-            Bsd(ar::Builder<File>),
-            Gnu(ar::GnuBuilder<File>),
-            NativeAr(&'a Path),
-        }
-
-        let mut builder = if self.config.use_native_ar {
-            BuilderKind::NativeAr(output)
-        } else if self.config.use_gnu_style_archive {
-            BuilderKind::Gnu(ar::GnuBuilder::new(
-                File::create(output).unwrap(),
-                self.entries
-                    .iter()
-                    .map(|(name, _)| name.as_bytes().to_vec())
-                    .collect(),
-            ))
-        } else {
-            BuilderKind::Bsd(ar::Builder::new(File::create(output).unwrap()))
-        };
-
-        let any_members = !self.entries.is_empty();
-
-        // Add all files
-        for (entry_name, entry) in self.entries.into_iter() {
-            match entry {
-                ArchiveEntry::FromArchive {
-                    archive_index,
-                    entry_index,
-                } => {
-                    let (ref src_archive_path, ref mut src_archive) =
-                        self.src_archives[archive_index];
-                    let entry = src_archive.jump_to_entry(entry_index).unwrap();
-                    let header = entry.header().clone();
-
-                    match builder {
-                        BuilderKind::Bsd(ref mut builder) => {
-                            builder.append(&header, entry).unwrap()
-                        }
-                        BuilderKind::Gnu(ref mut builder) => {
-                            builder.append(&header, entry).unwrap()
-                        }
-                        BuilderKind::NativeAr(archive_file) => {
-                            Command::new("ar")
-                                .arg("x")
-                                .arg(src_archive_path)
-                                .arg(&entry_name)
-                                .status()
-                                .unwrap();
-                            add_file_using_ar(archive_file, Path::new(&entry_name));
-                            std::fs::remove_file(entry_name).unwrap();
-                        }
-                    }
-                }
-                ArchiveEntry::File(file) =>
-                    match builder {
-                        BuilderKind::Bsd(ref mut builder) => {
-                            builder
-                                .append_file(entry_name.as_bytes(), &mut File::open(file).expect("file for bsd builder"))
-                                .unwrap()
-                        },
-                        BuilderKind::Gnu(ref mut builder) => {
-                            builder
-                                .append_file(entry_name.as_bytes(), &mut File::open(&file).expect(&format!("file {:?} for gnu builder", file)))
-                                .unwrap()
-                        },
-                        BuilderKind::NativeAr(archive_file) => add_file_using_ar(archive_file, &file),
-                    },
-            }
-        }
-
-        // Finalize archive
-        std::mem::drop(builder);
-
-        // Run ranlib to be able to link the archive
-        let status =
-            std::process::Command::new("ranlib").arg(output).status().expect("Couldn't run ranlib");
-
-        if !status.success() {
-            self.config.sess.emit_fatal(RanlibFailure::new(status.code()));
-        }
-
-        any_members
+        unimplemented!("creating dll imports is not yet supported");
     }
 }
diff --git a/compiler/rustc_codegen_gcc/src/errors.rs b/compiler/rustc_codegen_gcc/src/errors.rs
index 15ad90f9043..89fed7be131 100644
--- a/compiler/rustc_codegen_gcc/src/errors.rs
+++ b/compiler/rustc_codegen_gcc/src/errors.rs
@@ -17,18 +17,6 @@ impl IntoDiagnosticArg for ExitCode {
 }
 
 #[derive(Diagnostic)]
-#[diag(codegen_gcc_ranlib_failure)]
-pub(crate) struct RanlibFailure {
-    exit_code: ExitCode,
-}
-
-impl RanlibFailure {
-    pub fn new(exit_code: Option<i32>) -> Self {
-        RanlibFailure { exit_code: ExitCode(exit_code) }
-    }
-}
-
-#[derive(Diagnostic)]
 #[diag(codegen_gcc_invalid_monomorphization_basic_integer, code = "E0511")]
 pub(crate) struct InvalidMonomorphizationBasicInteger<'a> {
     #[primary_span]
@@ -227,7 +215,7 @@ pub(crate) struct InvalidMonomorphizationUnsupportedOperation<'a> {
 #[diag(codegen_gcc_linkage_const_or_mut_type)]
 pub(crate) struct LinkageConstOrMutType {
     #[primary_span]
-    pub span: Span
+    pub span: Span,
 }
 
 #[derive(Diagnostic)]
@@ -238,5 +226,5 @@ pub(crate) struct LTONotSupported;
 #[diag(codegen_gcc_unwinding_inline_asm)]
 pub(crate) struct UnwindingInlineAsm {
     #[primary_span]
-    pub span: Span
+    pub span: Span,
 }