Rollup merge of #144659 - mati865:gnullvm-vendor-libunwind, r=Kobzol

bootstrap: refactor mingw dist and fix gnullvm
Fixes#144533
The first two commits are NFC and only clean up the code, paving the way for the third commit. That said, I think they are worthwhile even without that fix - reusing the same function for two different outcomes was confusing.
The third commit is the fix for #144533, but due to the cross-compilation dance it requires a workaround to find the DLL since that logic really was meant only for Windows builders. That workaround is short-lived and will be removed as soon as gnullvm bootstraps itself.

Author: Zalathar

src/bootstrap/src/core/build_steps/dist.rs

@@ -174,36 +174,12 @@ fn find_files(files: &[&str], path: &[PathBuf]) -> Vec<PathBuf> {
  found
 }
 
-fnmake_win_dist(
-rust_root:&Path,
-plat_root:&Path,
-target:TargetSelection,
-builder:&Builder<'_>,
-){
+fnmake_win_dist(plat_root:&Path,target:TargetSelection,builder:&Builder<'_>){
 if builder.config.dry_run(){
 return;
 }
 
-//Ask gcc where it keeps its stuff
-letmut cmd = command(builder.cc(target));
- cmd.arg("-print-search-dirs");
-let gcc_out = cmd.run_capture_stdout(builder).stdout();
-
-letmut bin_path:Vec<_> = env::split_paths(&env::var_os("PATH").unwrap_or_default()).collect();
-letmut lib_path = Vec::new();
-
-for line in gcc_out.lines(){
-let idx = line.find(':').unwrap();
-let key = &line[..idx];
-let trim_chars:&[_] = &[' ','='];
-let value = env::split_paths(line[(idx + 1)..].trim_start_matches(trim_chars));
-
-if key == "programs"{
- bin_path.extend(value);
-}elseif key == "libraries"{
- lib_path.extend(value);
-}
-}
+let(bin_path, lib_path) = get_cc_search_dirs(target, builder);
 
 let compiler = if target == "i686-pc-windows-gnu"{
 "i686-w64-mingw32-gcc.exe"
@@ -213,12 +189,6 @@ fn make_win_dist(
 "gcc.exe"
 };
 let target_tools = [compiler,"ld.exe","dlltool.exe","libwinpthread-1.dll"];
-letmut rustc_dlls = vec!["libwinpthread-1.dll"];
-if target.starts_with("i686-"){
- rustc_dlls.push("libgcc_s_dw2-1.dll");
-}else{
- rustc_dlls.push("libgcc_s_seh-1.dll");
-}
 
 // Libraries necessary to link the windows-gnu toolchains.
 // System libraries will be preferred if they are available (see #67429).
@@ -274,25 +244,8 @@ fn make_win_dist(
 
 //Find mingw artifacts we want to bundle
 let target_tools = find_files(&target_tools,&bin_path);
-let rustc_dlls = find_files(&rustc_dlls,&bin_path);
 let target_libs = find_files(&target_libs,&lib_path);
 
-// Copy runtime dlls next to rustc.exe
-let rust_bin_dir = rust_root.join("bin/");
- fs::create_dir_all(&rust_bin_dir).expect("creating rust_bin_dir failed");
-for src in&rustc_dlls {
- builder.copy_link_to_folder(src,&rust_bin_dir);
-}
-
-if builder.config.lld_enabled{
-// rust-lld.exe also needs runtime dlls
-let rust_target_bin_dir = rust_root.join("lib/rustlib").join(target).join("bin");
- fs::create_dir_all(&rust_target_bin_dir).expect("creating rust_target_bin_dir failed");
-for src in&rustc_dlls {
- builder.copy_link_to_folder(src,&rust_target_bin_dir);
-}
-}
-
 //Copy platform tools to platform-specific bin directory
 let plat_target_bin_self_contained_dir =
  plat_root.join("lib/rustlib").join(target).join("bin/self-contained");
@@ -320,6 +273,82 @@ fn make_win_dist(
 }
 }
 
+fnruntime_dll_dist(rust_root:&Path,target:TargetSelection,builder:&Builder<'_>){
+if builder.config.dry_run(){
+return;
+}
+
+let(bin_path, libs_path) = get_cc_search_dirs(target, builder);
+
+letmut rustc_dlls = vec![];
+// windows-gnu and windows-gnullvm require different runtime libs
+if target.ends_with("windows-gnu"){
+ rustc_dlls.push("libwinpthread-1.dll");
+if target.starts_with("i686-"){
+ rustc_dlls.push("libgcc_s_dw2-1.dll");
+}else{
+ rustc_dlls.push("libgcc_s_seh-1.dll");
+}
+}elseif target.ends_with("windows-gnullvm"){
+ rustc_dlls.push("libunwind.dll");
+}else{
+panic!("Vendoring of runtime DLLs for `{target}` is not supported`");
+}
+// FIXME(#144656): Remove this whole `let ...`
+let bin_path = if target.ends_with("windows-gnullvm") && builder.host_target != target {
+ bin_path
+.into_iter()
+.chain(libs_path.iter().map(|path| path.with_file_name("bin")))
+.collect()
+}else{
+ bin_path
+};
+let rustc_dlls = find_files(&rustc_dlls,&bin_path);
+
+// Copy runtime dlls next to rustc.exe
+let rust_bin_dir = rust_root.join("bin/");
+ fs::create_dir_all(&rust_bin_dir).expect("creating rust_bin_dir failed");
+for src in&rustc_dlls {
+ builder.copy_link_to_folder(src,&rust_bin_dir);
+}
+
+if builder.config.lld_enabled{
+// rust-lld.exe also needs runtime dlls
+let rust_target_bin_dir = rust_root.join("lib/rustlib").join(target).join("bin");
+ fs::create_dir_all(&rust_target_bin_dir).expect("creating rust_target_bin_dir failed");
+for src in&rustc_dlls {
+ builder.copy_link_to_folder(src,&rust_target_bin_dir);
+}
+}
+}
+
+fnget_cc_search_dirs(
+target:TargetSelection,
+builder:&Builder<'_>,
+) -> (Vec<PathBuf>,Vec<PathBuf>){
+//Ask gcc where it keeps its stuff
+letmut cmd = command(builder.cc(target));
+ cmd.arg("-print-search-dirs");
+let gcc_out = cmd.run_capture_stdout(builder).stdout();
+
+letmut bin_path:Vec<_> = env::split_paths(&env::var_os("PATH").unwrap_or_default()).collect();
+letmut lib_path = Vec::new();
+
+for line in gcc_out.lines(){
+let idx = line.find(':').unwrap();
+let key = &line[..idx];
+let trim_chars:&[_] = &[' ','='];
+let value = env::split_paths(line[(idx + 1)..].trim_start_matches(trim_chars));
+
+if key == "programs"{
+ bin_path.extend(value);
+}elseif key == "libraries"{
+ lib_path.extend(value);
+}
+}
+(bin_path, lib_path)
+}
+
 #[derive(Debug,PartialOrd,Ord,Clone,Hash,PartialEq,Eq)]
 pubstructMingw{
 pubhost:TargetSelection,
@@ -350,11 +379,7 @@ impl Step for Mingw {
 letmut tarball = Tarball::new(builder,"rust-mingw",&host.triple);
  tarball.set_product_name("Rust MinGW");
 
-// The first argument is a "temporary directory" which is just
-// thrown away (this contains the runtime DLLs included in the rustc package
-// above) and the second argument is where to place all the MinGW components
-// (which is what we want).
-make_win_dist(&tmpdir(builder), tarball.image_dir(), host, builder);
+make_win_dist(tarball.image_dir(), host, builder);
 
 Some(tarball.generate())
 }
@@ -394,17 +419,14 @@ impl Step for Rustc {
 prepare_image(builder, compiler, tarball.image_dir());
 
 // On MinGW we've got a few runtime DLL dependencies that we need to
-// include. The first argument to this script is where to put these DLLs
-// (the image we're creating), and the second argument is a junk directory
-// to ignore all other MinGW stuff the script creates.
-//
+// include.
 // On 32-bit MinGW we're always including a DLL which needs some extra
 // licenses to distribute. On 64-bit MinGW we don't actually distribute
 // anything requiring us to distribute a license, but it's likely the
 // install will *also* include the rust-mingw package, which also needs
 // licenses, so to be safe we just include it here in all MinGW packages.
-if host.ends_with("pc-windows-gnu") && builder.config.dist_include_mingw_linker{
-make_win_dist(tarball.image_dir(),&tmpdir(builder), host, builder);
+if host.contains("pc-windows-gnu") && builder.config.dist_include_mingw_linker{
+runtime_dll_dist(tarball.image_dir(), host, builder);
  tarball.add_dir(builder.src.join("src/etc/third-party"),"share/doc");
 }