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

usamoi · usamoi · commit 21dd997aec1a · 2025-10-06T08:56:40.000+08:00
diff --git a/compiler/rustc_attr_parsing/messages.ftl b/compiler/rustc_attr_parsing/messages.ftl
@@ -1,5 +1,5 @@
 attr_parsing_as_needed_compatibility =
-    linking modifier `as-needed` is only compatible with `dylib` and `framework` linking kinds
+    linking modifier `as-needed` is only compatible with `dylib`, `framework` and `raw-dylib` linking kinds
 
 attr_parsing_bundle_needs_static =
     linking modifier `bundle` is only compatible with `static` linking kind
diff --git a/compiler/rustc_attr_parsing/src/attributes/link_attrs.rs b/compiler/rustc_attr_parsing/src/attributes/link_attrs.rs
@@ -180,7 +180,8 @@ impl<S: Stage> CombineAttributeParser<S> for LinkParser {
                     }
 
                     (sym::as_dash_needed, Some(NativeLibKind::Dylib { as_needed }))
-                    | (sym::as_dash_needed, Some(NativeLibKind::Framework { as_needed })) => {
+                    | (sym::as_dash_needed, Some(NativeLibKind::Framework { as_needed }))
+                    | (sym::as_dash_needed, Some(NativeLibKind::RawDylib { as_needed })) => {
                         report_unstable_modifier!(native_link_modifiers_as_needed);
                         assign_modifier(as_needed)
                     }
@@ -219,12 +220,12 @@ impl<S: Stage> CombineAttributeParser<S> for LinkParser {
 
         // Do this outside of the loop so that `import_name_type` can be specified before `kind`.
         if let Some((_, span)) = import_name_type {
-            if kind != Some(NativeLibKind::RawDylib) {
+            if !matches!(kind, Some(NativeLibKind::RawDylib { .. })) {
                 cx.emit_err(ImportNameTypeRaw { span });
             }
         }
 
-        if let Some(NativeLibKind::RawDylib) = kind
+        if let Some(NativeLibKind::RawDylib { .. }) = kind
             && name.as_str().contains('\0')
         {
             cx.emit_err(RawDylibNoNul { span: name_span });
@@ -315,7 +316,7 @@ impl LinkParser {
                     cx.emit_err(RawDylibOnlyWindows { span: nv.value_span });
                 }
 
-                NativeLibKind::RawDylib
+                NativeLibKind::RawDylib { as_needed: None }
             }
             sym::link_dash_arg => {
                 if !features.link_arg_attribute() {
diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/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 => {}
diff --git a/compiler/rustc_codegen_ssa/src/back/link/raw_dylib.rs b/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()
 }
diff --git a/compiler/rustc_hir/src/attrs/data_structures.rs b/compiler/rustc_hir/src/attrs/data_structures.rs
@@ -309,7 +309,10 @@ pub enum NativeLibKind {
     },
     /// Dynamic library (e.g. `foo.dll` on Windows) without a corresponding import library.
     /// On Linux, it refers to a generated shared library stub.
-    RawDylib,
+    RawDylib {
+        /// Whether the dynamic library will be linked only if it satisfies some undefined symbols
+        as_needed: Option<bool>,
+    },
     /// A macOS-specific kind of dynamic libraries.
     Framework {
         /// Whether the framework will be linked only if it satisfies some undefined symbols
@@ -332,11 +335,10 @@ impl NativeLibKind {
             NativeLibKind::Static { bundle, whole_archive } => {
                 bundle.is_some() || whole_archive.is_some()
             }
-            NativeLibKind::Dylib { as_needed } | NativeLibKind::Framework { as_needed } => {
-                as_needed.is_some()
-            }
-            NativeLibKind::RawDylib
-            | NativeLibKind::Unspecified
+            NativeLibKind::Dylib { as_needed }
+            | NativeLibKind::Framework { as_needed }
+            | NativeLibKind::RawDylib { as_needed } => as_needed.is_some(),
+            NativeLibKind::Unspecified
             | NativeLibKind::LinkArg
             | NativeLibKind::WasmImportModule => false,
         }
@@ -349,7 +351,9 @@ impl NativeLibKind {
     pub fn is_dllimport(&self) -> bool {
         matches!(
             self,
-            NativeLibKind::Dylib { .. } | NativeLibKind::RawDylib | NativeLibKind::Unspecified
+            NativeLibKind::Dylib { .. }
+                | NativeLibKind::RawDylib { .. }
+                | NativeLibKind::Unspecified
         )
     }
 }
diff --git a/compiler/rustc_metadata/src/native_libs.rs b/compiler/rustc_metadata/src/native_libs.rs
@@ -218,7 +218,7 @@ impl<'tcx> Collector<'tcx> {
                 .flatten()
         {
             let dll_imports = match attr.kind {
-                NativeLibKind::RawDylib => foreign_items
+                NativeLibKind::RawDylib { .. } => foreign_items
                     .iter()
                     .map(|&child_item| {
                         self.build_dll_import(
diff --git a/compiler/rustc_session/src/config/native_libs.rs b/compiler/rustc_session/src/config/native_libs.rs
@@ -135,7 +135,8 @@ fn parse_and_apply_modifier(cx: &ParseNativeLibCx<'_>, modifier: &str, native_li
         ),
 
         ("as-needed", NativeLibKind::Dylib { as_needed })
-        | ("as-needed", NativeLibKind::Framework { as_needed }) => {
+        | ("as-needed", NativeLibKind::Framework { as_needed })
+        | ("as-needed", NativeLibKind::RawDylib { as_needed }) => {
             cx.on_unstable_value(
                 "linking modifier `as-needed` is unstable",
                 ", the `-Z unstable-options` flag must also be passed to use it",
diff --git a/tests/ui/linkage-attr/raw-dylib/elf/as_needed.rs b/tests/ui/linkage-attr/raw-dylib/elf/as_needed.rs
@@ -0,0 +1,43 @@
+//@ only-elf
+//@ needs-dynamic-linking
+
+//@ only-gnu
+//@ only-x86_64
+//@ revisions: as_needed no_as_needed no_modifier merge_1 merge_2 merge_3 merge_4
+
+//@ [as_needed] run-pass
+//@ [no_as_needed] run-fail
+//@ [no_modifier] run-pass
+//@ [merge_1] run-fail
+//@ [merge_2] run-fail
+//@ [merge_3] run-fail
+//@ [merge_4] run-pass
+
+#![allow(incomplete_features)]
+#![feature(raw_dylib_elf)]
+#![feature(native_link_modifiers_as_needed)]
+
+#[cfg_attr(
+    as_needed,
+    link(name = "taiqannf1y28z2rw", kind = "raw-dylib", modifiers = "+as-needed")
+)]
+#[cfg_attr(
+    no_as_needed,
+    link(name = "taiqannf1y28z2rw", kind = "raw-dylib", modifiers = "-as-needed")
+)]
+#[cfg_attr(no_modifier, link(name = "taiqannf1y28z2rw", kind = "raw-dylib"))]
+unsafe extern "C" {}
+
+#[cfg_attr(merge_1, link(name = "k9nm7qxoa79bg7e6", kind = "raw-dylib", modifiers = "+as-needed"))]
+#[cfg_attr(merge_2, link(name = "k9nm7qxoa79bg7e6", kind = "raw-dylib", modifiers = "-as-needed"))]
+#[cfg_attr(merge_3, link(name = "k9nm7qxoa79bg7e6", kind = "raw-dylib", modifiers = "-as-needed"))]
+#[cfg_attr(merge_4, link(name = "k9nm7qxoa79bg7e6", kind = "raw-dylib", modifiers = "+as-needed"))]
+unsafe extern "C" {}
+
+#[cfg_attr(merge_1, link(name = "k9nm7qxoa79bg7e6", kind = "raw-dylib", modifiers = "-as-needed"))]
+#[cfg_attr(merge_2, link(name = "k9nm7qxoa79bg7e6", kind = "raw-dylib", modifiers = "+as-needed"))]
+#[cfg_attr(merge_3, link(name = "k9nm7qxoa79bg7e6", kind = "raw-dylib", modifiers = "-as-needed"))]
+#[cfg_attr(merge_4, link(name = "k9nm7qxoa79bg7e6", kind = "raw-dylib", modifiers = "+as-needed"))]
+unsafe extern "C" {}
+
+fn main() {}

Original file line number	Diff line number	Diff line change
`@@ -180,7 +180,8 @@ impl<S: Stage> CombineAttributeParser<S> for LinkParser {`
`180`	`180`	`}`
`181`	`181`
`182`	`182`	`(sym::as_dash_needed, Some(NativeLibKind::Dylib { as_needed }))`
`183`		`- \| (sym::as_dash_needed, Some(NativeLibKind::Framework { as_needed })) => {`
	`183`	`+ \| (sym::as_dash_needed, Some(NativeLibKind::Framework { as_needed }))`
	`184`	`+ \| (sym::as_dash_needed, Some(NativeLibKind::RawDylib { as_needed })) => {`
`184`	`185`	`report_unstable_modifier!(native_link_modifiers_as_needed);`
`185`	`186`	`assign_modifier(as_needed)`
`186`	`187`	`}`
`@@ -219,12 +220,12 @@ impl<S: Stage> CombineAttributeParser<S> for LinkParser {`
`219`	`220`
`220`	`221`	// Do this outside of the loop so that `import_name_type` can be specified before `kind`.
`221`	`222`	`if let Some((_, span)) = import_name_type {`
`222`		`- if kind != Some(NativeLibKind::RawDylib) {`
	`223`	`+ if !matches!(kind, Some(NativeLibKind::RawDylib { .. })) {`
`223`	`224`	`cx.emit_err(ImportNameTypeRaw { span });`
`224`	`225`	`}`
`225`	`226`	`}`
`226`	`227`
`227`		`- if let Some(NativeLibKind::RawDylib) = kind`
	`228`	`+ if let Some(NativeLibKind::RawDylib { .. }) = kind`
`228`	`229`	`&& name.as_str().contains('\0')`
`229`	`230`	`{`
`230`	`231`	`cx.emit_err(RawDylibNoNul { span: name_span });`
`@@ -315,7 +316,7 @@ impl LinkParser {`
`315`	`316`	`cx.emit_err(RawDylibOnlyWindows { span: nv.value_span });`
`316`	`317`	`}`
`317`	`318`
`318`		`- NativeLibKind::RawDylib`
	`319`	`+ NativeLibKind::RawDylib { as_needed: None }`
`319`	`320`	`}`
`320`	`321`	`sym::link_dash_arg => {`
`321`	`322`	`if !features.link_arg_attribute() {`
Original file line number	Diff line number	Diff line change
`@@ -1490,7 +1490,7 @@ fn print_native_static_libs(`
`1490`	`1490`	`NativeLibKind::Static { bundle: None \| Some(true), .. }`
`1491`	`1491`	`\| NativeLibKind::LinkArg`
`1492`	`1492`	`\| NativeLibKind::WasmImportModule`
`1493`		`- \| NativeLibKind::RawDylib => None,`
	`1493`	`+ \| NativeLibKind::RawDylib { .. } => None,`
`1494`	`1494`	`}`
`1495`	`1495`	`})`
`1496`	`1496`	`// deduplication of consecutive repeated libraries, see rust-lang/rust#113209`
`@@ -2364,13 +2364,13 @@ fn linker_with_args(`
`2364`	`2364`	`cmd.add_object(&output_path);`
`2365`	`2365`	`}`
`2366`	`2366`	`} else {`
`2367`		`- for link_path in raw_dylib::create_raw_dylib_elf_stub_shared_objects(`
	`2367`	`+ for (link_path, as_needed) in raw_dylib::create_raw_dylib_elf_stub_shared_objects(`
`2368`	`2368`	`sess,`
`2369`	`2369`	`codegen_results.crate_info.used_libraries.iter(),`
`2370`	`2370`	`&raw_dylib_dir,`
`2371`	`2371`	`) {`
`2372`	`2372`	`// Always use verbatim linkage, see comments in create_raw_dylib_elf_stub_shared_objects.`
`2373`		`- cmd.link_dylib_by_name(&link_path, true, false);`
	`2373`	`+ cmd.link_dylib_by_name(&link_path, true, as_needed);`
`2374`	`2374`	`}`
`2375`	`2375`	`}`
`2376`	`2376`	`// 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(`
`2411`	`2411`	`cmd.add_object(&output_path);`
`2412`	`2412`	`}`
`2413`	`2413`	`} else {`
`2414`		`- for link_path in raw_dylib::create_raw_dylib_elf_stub_shared_objects(`
	`2414`	`+ for (link_path, as_needed) in raw_dylib::create_raw_dylib_elf_stub_shared_objects(`
`2415`	`2415`	`sess,`
`2416`	`2416`	`native_libraries_from_nonstatics,`
`2417`	`2417`	`&raw_dylib_dir,`
`2418`	`2418`	`) {`
`2419`	`2419`	`// Always use verbatim linkage, see comments in create_raw_dylib_elf_stub_shared_objects.`
`2420`		`- cmd.link_dylib_by_name(&link_path, true, false);`
	`2420`	`+ cmd.link_dylib_by_name(&link_path, true, as_needed);`
`2421`	`2421`	`}`
`2422`	`2422`	`}`
`2423`	`2423`
`@@ -2726,7 +2726,7 @@ fn add_native_libs_from_crate(`
`2726`	`2726`	`cmd.link_framework_by_name(name, verbatim, as_needed.unwrap_or(true))`
`2727`	`2727`	`}`
`2728`	`2728`	`}`
`2729`		`- NativeLibKind::RawDylib => {`
	`2729`	`+ NativeLibKind::RawDylib { as_needed: _ } => {`
`2730`	`2730`	// Handled separately in `linker_with_args`.
`2731`	`2731`	`}`
`2732`	`2732`	`NativeLibKind::WasmImportModule => {}`
Original file line number	Diff line number	Diff line change
`@@ -218,7 +218,7 @@ impl<'tcx> Collector<'tcx> {`
`218`	`218`	`.flatten()`
`219`	`219`	`{`
`220`	`220`	`let dll_imports = match attr.kind {`
`221`		`- NativeLibKind::RawDylib => foreign_items`
	`221`	`+ NativeLibKind::RawDylib { .. } => foreign_items`
`222`	`222`	`.iter()`
`223`	`223`	`.map(\|&child_item\| {`
`224`	`224`	`self.build_dll_import(`