Make create_dll_import_lib easier to implement

Cargo.lock

@@ -231,11 +231,11 @@ dependencies = [
 
 [[package]]
 name = "ar_archive_writer"
-version = "0.3.0"
+version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8412a2d690663356cba5a2532f3ed55d1e8090743bc6695b88403b27df67733"
+checksum = "3f2bcb7cf51decfbbfc7ef476e28b0775b13e5eb1190f8b7df145cd53d4f4374"
 dependencies = [
- "object 0.35.0",
+ "object 0.36.2",
 ]
 
 [[package]]
@@ -2573,15 +2573,6 @@ dependencies = [
  "ruzstd 0.5.0",
 ]
 
-[[package]]
-name = "object"
-version = "0.35.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b8ec7ab813848ba4522158d5517a6093db1ded27575b070f4177b8d12b41db5e"
-dependencies = [
- "memchr",
-]
-
 [[package]]
 name = "object"
 version = "0.36.2"

compiler/rustc_codegen_cranelift/src/archive.rs

@@ -1,4 +1,4 @@
-use std::path::{Path, PathBuf};
+use std::path::Path;
 
 use rustc_codegen_ssa::back::archive::{
     ArArchiveBuilder, ArchiveBuilder, ArchiveBuilderBuilder, DEFAULT_OBJECT_READER,
@@ -16,10 +16,9 @@ impl ArchiveBuilderBuilder for ArArchiveBuilderBuilder {
         &self,
         sess: &Session,
         _lib_name: &str,
-        _dll_imports: &[rustc_session::cstore::DllImport],
-        _tmpdir: &Path,
-        _is_direct_dependency: bool,
-    ) -> PathBuf {
+        _import_name_and_ordinal_vector: Vec<(String, Option<u16>)>,
+        _output_path: &Path,
+    ) {
         sess.dcx().fatal("raw-dylib is not yet supported by rustc_codegen_cranelift");
     }
 }

compiler/rustc_codegen_gcc/src/archive.rs

@@ -1,9 +1,8 @@
-use std::path::{Path, PathBuf};
+use std::path::Path;
 
 use rustc_codegen_ssa::back::archive::{
     ArArchiveBuilder, ArchiveBuilder, ArchiveBuilderBuilder, DEFAULT_OBJECT_READER,
 };
-use rustc_session::cstore::DllImport;
 use rustc_session::Session;
 
 pub(crate) struct ArArchiveBuilderBuilder;
@@ -17,10 +16,9 @@ impl ArchiveBuilderBuilder for ArArchiveBuilderBuilder {
         &self,
         _sess: &Session,
         _lib_name: &str,
-        _dll_imports: &[DllImport],
-        _tmpdir: &Path,
-        _is_direct_dependency: bool,
-    ) -> PathBuf {
+        _import_name_and_ordinal_vector: Vec<(String, Option<u16>)>,
+        _output_path: &Path,
+    ) {
         unimplemented!("creating dll imports is not yet supported");
     }
 }

compiler/rustc_codegen_llvm/messages.ftl

@@ -1,23 +1,13 @@
 codegen_llvm_copy_bitcode = failed to copy bitcode to object file: {$err}
 
-codegen_llvm_dlltool_fail_import_library =
-    Dlltool could not create import library with {$dlltool_path} {$dlltool_args}:
-    {$stdout}
-    {$stderr}
-
 codegen_llvm_dynamic_linking_with_lto =
     cannot prefer dynamic linking when performing LTO
     .note = only 'staticlib', 'bin', and 'cdylib' outputs are supported with LTO
 
-codegen_llvm_error_calling_dlltool =
-    Error calling dlltool '{$dlltool_path}': {$error}
 
 codegen_llvm_error_creating_import_library =
     Error creating import library for {$lib_name}: {$error}
 
-codegen_llvm_error_writing_def_file =
-    Error writing .DEF file: {$error}
-
 codegen_llvm_fixed_x18_invalid_arch = the `-Zfixed-x18` flag is not supported on the `{$arch}` architecture
 
 codegen_llvm_from_llvm_diag = {$message}

compiler/rustc_codegen_llvm/src/back/archive.rs

@@ -1,21 +1,19 @@
 //! A helper class for dealing with static archives
 
-use std::ffi::{c_char, c_void, CStr, CString, OsString};
+use std::ffi::{c_char, c_void, CStr, CString};
 use std::path::{Path, PathBuf};
-use std::{env, io, mem, ptr, str};
+use std::{io, mem, ptr, str};
 
 use rustc_codegen_ssa::back::archive::{
-    try_extract_macho_fat_archive, ArArchiveBuilder, ArchiveBuildFailure, ArchiveBuilder,
-    ArchiveBuilderBuilder, ObjectReader, UnknownArchiveKind, DEFAULT_OBJECT_READER,
+    create_mingw_dll_import_lib, try_extract_macho_fat_archive, ArArchiveBuilder,
+    ArchiveBuildFailure, ArchiveBuilder, ArchiveBuilderBuilder, ObjectReader, UnknownArchiveKind,
+    DEFAULT_OBJECT_READER,
 };
-use rustc_session::cstore::DllImport;
+use rustc_codegen_ssa::common;
 use rustc_session::Session;
 use tracing::trace;
 
-use crate::common;
-use crate::errors::{
-    DlltoolFailImportLibrary, ErrorCallingDllTool, ErrorCreatingImportLibrary, ErrorWritingDEFFile,
-};
+use crate::errors::ErrorCreatingImportLibrary;
 use crate::llvm::archive_ro::{ArchiveRO, Child};
 use crate::llvm::{self, ArchiveKind, LLVMMachineType, LLVMRustCOFFShortExport};
 
@@ -119,116 +117,21 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
         &self,
         sess: &Session,
         lib_name: &str,
-        dll_imports: &[DllImport],
-        tmpdir: &Path,
-        is_direct_dependency: bool,
-    ) -> PathBuf {
-        let name_suffix = if is_direct_dependency { "_imports" } else { "_imports_indirect" };
-        let output_path = tmpdir.join(format!("{lib_name}{name_suffix}.lib"));
-
-        let target = &sess.target;
-        let mingw_gnu_toolchain = common::is_mingw_gnu_toolchain(target);
-
-        let import_name_and_ordinal_vector: Vec<(String, Option<u16>)> = dll_imports
-            .iter()
-            .map(|import: &DllImport| {
-                if sess.target.arch == "x86" {
-                    (
-                        common::i686_decorated_name(import, mingw_gnu_toolchain, false),
-                        import.ordinal(),
-                    )
-                } else {
-                    (import.name.to_string(), import.ordinal())
-                }
-            })
-            .collect();
-
-        if mingw_gnu_toolchain {
+        import_name_and_ordinal_vector: Vec<(String, Option<u16>)>,
+        output_path: &Path,
+    ) {
+        if common::is_mingw_gnu_toolchain(&sess.target) {
             // The binutils linker used on -windows-gnu targets cannot read the import
             // libraries generated by LLVM: in our attempts, the linker produced an .EXE
             // that loaded but crashed with an AV upon calling one of the imported
             // functions. Therefore, use binutils to create the import library instead,
             // by writing a .DEF file to the temp dir and calling binutils's dlltool.
-            let def_file_path = tmpdir.join(format!("{lib_name}{name_suffix}.def"));
-
-            let def_file_content = format!(
-                "EXPORTS\n{}",
-                import_name_and_ordinal_vector
-                    .into_iter()
-                    .map(|(name, ordinal)| {
-                        match ordinal {
-                            Some(n) => format!("{name} @{n} NONAME"),
-                            None => name,
-                        }
-                    })
-                    .collect::<Vec<String>>()
-                    .join("\n")
+            create_mingw_dll_import_lib(
+                sess,
+                lib_name,
+                import_name_and_ordinal_vector,
+                output_path,
             );
-
-            match std::fs::write(&def_file_path, def_file_content) {
-                Ok(_) => {}
-                Err(e) => {
-                    sess.dcx().emit_fatal(ErrorWritingDEFFile { error: e });
-                }
-            };
-
-            // --no-leading-underscore: For the `import_name_type` feature to work, we need to be
-            // able to control the *exact* spelling of each of the symbols that are being imported:
-            // hence we don't want `dlltool` adding leading underscores automatically.
-            let dlltool = find_binutils_dlltool(sess);
-            let temp_prefix = {
-                let mut path = PathBuf::from(&output_path);
-                path.pop();
-                path.push(lib_name);
-                path
-            };
-            // dlltool target architecture args from:
-            // https://github.com/llvm/llvm-project-release-prs/blob/llvmorg-15.0.6/llvm/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp#L69
-            let (dlltool_target_arch, dlltool_target_bitness) = match sess.target.arch.as_ref() {
-                "x86_64" => ("i386:x86-64", "--64"),
-                "x86" => ("i386", "--32"),
-                "aarch64" => ("arm64", "--64"),
-                "arm" => ("arm", "--32"),
-                _ => panic!("unsupported arch {}", sess.target.arch),
-            };
-            let mut dlltool_cmd = std::process::Command::new(&dlltool);
-            dlltool_cmd
-                .arg("-d")
-                .arg(def_file_path)
-                .arg("-D")
-                .arg(lib_name)
-                .arg("-l")
-                .arg(&output_path)
-                .arg("-m")
-                .arg(dlltool_target_arch)
-                .arg("-f")
-                .arg(dlltool_target_bitness)
-                .arg("--no-leading-underscore")
-                .arg("--temp-prefix")
-                .arg(temp_prefix);
-
-            match dlltool_cmd.output() {
-                Err(e) => {
-                    sess.dcx().emit_fatal(ErrorCallingDllTool {
-                        dlltool_path: dlltool.to_string_lossy(),
-                        error: e,
-                    });
-                }
-                // dlltool returns '0' on failure, so check for error output instead.
-                Ok(output) if !output.stderr.is_empty() => {
-                    sess.dcx().emit_fatal(DlltoolFailImportLibrary {
-                        dlltool_path: dlltool.to_string_lossy(),
-                        dlltool_args: dlltool_cmd
-                            .get_args()
-                            .map(|arg| arg.to_string_lossy())
-                            .collect::<Vec<_>>()
-                            .join(" "),
-                        stdout: String::from_utf8_lossy(&output.stdout),
-                        stderr: String::from_utf8_lossy(&output.stderr),
-                    })
-                }
-                _ => {}
-            }
         } else {
             // we've checked for \0 characters in the library name already
             let dll_name_z = CString::new(lib_name).unwrap();
@@ -240,9 +143,9 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
             trace!("  output_path {}", output_path.display());
             trace!(
                 "  import names: {}",
-                dll_imports
+                import_name_and_ordinal_vector
                     .iter()
-                    .map(|import| import.name.to_string())
+                    .map(|(name, _ordinal)| name.clone())
                     .collect::<Vec<_>>()
                     .join(", "),
             );
@@ -279,9 +182,7 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
                     error: llvm::last_error().unwrap_or("unknown LLVM error".to_string()),
                 });
             }
-        };
-
-        output_path
+        }
     }
 }
 
@@ -455,39 +356,3 @@ impl<'a> LlvmArchiveBuilder<'a> {
 fn string_to_io_error(s: String) -> io::Error {
     io::Error::new(io::ErrorKind::Other, format!("bad archive: {s}"))
 }
-
-fn find_binutils_dlltool(sess: &Session) -> OsString {
-    assert!(sess.target.options.is_like_windows && !sess.target.options.is_like_msvc);
-    if let Some(dlltool_path) = &sess.opts.cg.dlltool {
-        return dlltool_path.clone().into_os_string();
-    }
-
-    let tool_name: OsString = if sess.host.options.is_like_windows {
-        // If we're compiling on Windows, always use "dlltool.exe".
-        "dlltool.exe"
-    } else {
-        // On other platforms, use the architecture-specific name.
-        match sess.target.arch.as_ref() {
-            "x86_64" => "x86_64-w64-mingw32-dlltool",
-            "x86" => "i686-w64-mingw32-dlltool",
-            "aarch64" => "aarch64-w64-mingw32-dlltool",
-
-            // For non-standard architectures (e.g., aarch32) fallback to "dlltool".
-            _ => "dlltool",
-        }
-    }
-    .into();
-
-    // NOTE: it's not clear how useful it is to explicitly search PATH.
-    for dir in env::split_paths(&env::var_os("PATH").unwrap_or_default()) {
-        let full_path = dir.join(&tool_name);
-        if full_path.is_file() {
-            return full_path.into_os_string();
-        }
-    }
-
-    // The user didn't specify the location of the dlltool binary, and we weren't able
-    // to find the appropriate one on the PATH. Just return the name of the tool
-    // and let the invocation fail with a hopefully useful error message.
-    tool_name
-}

compiler/rustc_codegen_llvm/src/callee.rs

@@ -4,13 +4,14 @@
 //! and methods are represented as just a fn ptr and not a full
 //! closure.
 
+use rustc_codegen_ssa::common;
 use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt};
 use rustc_middle::ty::{self, Instance, TypeVisitableExt};
 use tracing::debug;
 
 use crate::context::CodegenCx;
 use crate::value::Value;
-use crate::{attributes, common, llvm};
+use crate::{attributes, llvm};
 
 /// Codegens a reference to a fn/method item, monomorphizing and
 /// inlining as it goes.
@@ -46,7 +47,7 @@ pub fn get_fn<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>, instance: Instance<'tcx>) ->
     } else {
         let instance_def_id = instance.def_id();
         let llfn = if tcx.sess.target.arch == "x86"
-            && let Some(dllimport) = common::get_dllimport(tcx, instance_def_id, sym)
+            && let Some(dllimport) = crate::common::get_dllimport(tcx, instance_def_id, sym)
         {
             // Fix for https://github.com/rust-lang/rust/issues/104453
             // On x86 Windows, LLVM uses 'L' as the prefix for any private