support link modifier as-needed for raw-dylib-elf

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -1490,7 +1490,7 @@ fn print_native_static_libs(
                 NativeLibKind::Static { bundle: None | Some(true), .. }
                 | NativeLibKind::LinkArg
                 | NativeLibKind::WasmImportModule
-                | NativeLibKind::RawDylib => None,
+                | NativeLibKind::RawDylib { .. } => None,
             }
         })
         // deduplication of consecutive repeated libraries, see rust-lang/rust#113209
@@ -2364,13 +2364,13 @@ fn linker_with_args(
             cmd.add_object(&output_path);
         }
     } else {
-        for link_path in raw_dylib::create_raw_dylib_elf_stub_shared_objects(
+        for (link_path, as_needed) in raw_dylib::create_raw_dylib_elf_stub_shared_objects(
             sess,
             codegen_results.crate_info.used_libraries.iter(),
             &raw_dylib_dir,
         ) {
             // Always use verbatim linkage, see comments in create_raw_dylib_elf_stub_shared_objects.
-            cmd.link_dylib_by_name(&link_path, true, false);
+            cmd.link_dylib_by_name(&link_path, true, as_needed);
         }
     }
     // As with add_upstream_native_libraries, we need to add the upstream raw-dylib symbols in case
@@ -2411,13 +2411,13 @@ fn linker_with_args(
             cmd.add_object(&output_path);
         }
     } else {
-        for link_path in raw_dylib::create_raw_dylib_elf_stub_shared_objects(
+        for (link_path, as_needed) in raw_dylib::create_raw_dylib_elf_stub_shared_objects(
             sess,
             native_libraries_from_nonstatics,
             &raw_dylib_dir,
         ) {
             // Always use verbatim linkage, see comments in create_raw_dylib_elf_stub_shared_objects.
-            cmd.link_dylib_by_name(&link_path, true, false);
+            cmd.link_dylib_by_name(&link_path, true, as_needed);
         }
     }
 
@@ -2726,7 +2726,7 @@ fn add_native_libs_from_crate(
                     cmd.link_framework_by_name(name, verbatim, as_needed.unwrap_or(true))
                 }
             }
-            NativeLibKind::RawDylib => {
+            NativeLibKind::RawDylib { as_needed: _ } => {
                 // Handled separately in `linker_with_args`.
             }
             NativeLibKind::WasmImportModule => {}

compiler/rustc_codegen_ssa/src/back/link/raw_dylib.rs

@@ -31,7 +31,7 @@ fn collate_raw_dylibs_windows<'a>(
     let mut dylib_table = FxIndexMap::<String, FxIndexMap<Symbol, &DllImport>>::default();
 
     for lib in used_libraries {
-        if lib.kind == NativeLibKind::RawDylib {
+        if let NativeLibKind::RawDylib { .. } = lib.kind {
             let ext = if lib.verbatim { "" } else { ".dll" };
             let name = format!("{}{}", lib.name, ext);
             let imports = dylib_table.entry(name.clone()).or_default();
@@ -128,12 +128,12 @@ pub(super) fn create_raw_dylib_dll_import_libs<'a>(
 fn collate_raw_dylibs_elf<'a>(
     sess: &Session,
     used_libraries: impl IntoIterator<Item = &'a NativeLib>,
-) -> Vec<(String, Vec<DllImport>)> {
+) -> Vec<(String, Vec<DllImport>, bool)> {
     // Use index maps to preserve original order of imports and libraries.
-    let mut dylib_table = FxIndexMap::<String, FxIndexMap<Symbol, &DllImport>>::default();
+    let mut dylib_table = FxIndexMap::<String, (FxIndexMap<Symbol, &DllImport>, bool)>::default();
 
     for lib in used_libraries {
-        if lib.kind == NativeLibKind::RawDylib {
+        if let NativeLibKind::RawDylib { as_needed } = lib.kind {
             let filename = if lib.verbatim {
                 lib.name.as_str().to_owned()
             } else {
@@ -142,17 +142,19 @@ fn collate_raw_dylibs_elf<'a>(
                 format!("{prefix}{}{ext}", lib.name)
             };
 
-            let imports = dylib_table.entry(filename.clone()).or_default();
+            let (stub_imports, stub_as_needed) =
+                dylib_table.entry(filename.clone()).or_insert((Default::default(), true));
             for import in &lib.dll_imports {
-                imports.insert(import.name, import);
+                stub_imports.insert(import.name, import);
             }
+            *stub_as_needed = *stub_as_needed && as_needed.unwrap_or(true);
         }
     }
     sess.dcx().abort_if_errors();
     dylib_table
         .into_iter()
-        .map(|(name, imports)| {
-            (name, imports.into_iter().map(|(_, import)| import.clone()).collect())
+        .map(|(name, (imports, as_needed))| {
+            (name, imports.into_iter().map(|(_, import)| import.clone()).collect(), as_needed)
         })
         .collect()
 }
@@ -161,10 +163,10 @@ pub(super) fn create_raw_dylib_elf_stub_shared_objects<'a>(
     sess: &Session,
     used_libraries: impl IntoIterator<Item = &'a NativeLib>,
     raw_dylib_so_dir: &Path,
-) -> Vec<String> {
+) -> Vec<(String, bool)> {
     collate_raw_dylibs_elf(sess, used_libraries)
         .into_iter()
-        .map(|(load_filename, raw_dylib_imports)| {
+        .map(|(load_filename, raw_dylib_imports, as_needed)| {
             use std::hash::Hash;
 
             // `load_filename` is the *target/loader* filename that will end up in NEEDED.
@@ -205,7 +207,7 @@ pub(super) fn create_raw_dylib_elf_stub_shared_objects<'a>(
                 });
             };
 
-            temporary_lib_name
+            (temporary_lib_name, as_needed)
         })
         .collect()
 }