Auto merge of #128370 - petrochenkov:libsearch, r=<try>

linker: Pass fewer search directories to the linker

Work in progress.

try-job: dist-x86_64-musl
try-job: dist-x86_64-mingw
try-job: dist-x86_64-msvc
try-job: dist-x86_64-apple
try-job: dist-various-1
try-job: dist-various-2

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -2065,16 +2065,16 @@ fn add_local_crate_metadata_objects(
 }
 
 /// Add sysroot and other globally set directories to the directory search list.
-fn add_library_search_dirs(cmd: &mut dyn Linker, sess: &Session, self_contained: bool) {
+fn add_library_search_dirs(_cmd: &mut dyn Linker, sess: &Session, self_contained: bool) {
     // The default library location, we need this to find the runtime.
     // The location of crates will be determined as needed.
-    let lib_path = sess.target_filesearch(PathKind::All).get_lib_path();
-    cmd.include_path(&fix_windows_verbatim_for_gcc(&lib_path));
+    let _lib_path = sess.target_filesearch(PathKind::All).get_lib_path();
+    // cmd.include_path(&fix_windows_verbatim_for_gcc(&lib_path));
 
     // Special directory with libraries used only in self-contained linkage mode
     if self_contained {
-        let lib_path = sess.target_filesearch(PathKind::All).get_self_contained_lib_path();
-        cmd.include_path(&fix_windows_verbatim_for_gcc(&lib_path));
+        let _lib_path = sess.target_filesearch(PathKind::All).get_self_contained_lib_path();
+        // cmd.include_path(&fix_windows_verbatim_for_gcc(&lib_path));
     }
 }
 
@@ -2638,14 +2638,13 @@ fn add_local_native_libraries(
     link_output_kind: LinkOutputKind,
 ) {
     if sess.opts.unstable_opts.link_native_libraries {
-        // User-supplied library search paths (-L on the command line). These are the same paths
-        // used to find Rust crates, so some of them may have been added already by the previous
-        // crate linking code. This only allows them to be found at compile time so it is still
-        // entirely up to outside forces to make sure that library can be found at runtime.
-        for search_path in sess.target_filesearch(PathKind::All).search_paths() {
-            match search_path.kind {
-                PathKind::Framework => cmd.framework_path(&search_path.dir),
-                _ => cmd.include_path(&fix_windows_verbatim_for_gcc(&search_path.dir)),
+        for search_path in sess.target_filesearch(PathKind::Native).cli_search_paths() {
+            cmd.include_path(&fix_windows_verbatim_for_gcc(&search_path.dir));
+        }
+        for search_path in sess.target_filesearch(PathKind::Framework).cli_search_paths() {
+            // Contrary to the `-L` docs only framework-specific paths are considered here.
+            if search_path.kind != PathKind::All {
+                cmd.framework_path(&search_path.dir);
             }
         }
     }
@@ -3012,9 +3011,9 @@ fn add_apple_sdk(cmd: &mut dyn Linker, sess: &Session, flavor: LinkerFlavor) {
         // search path.
 
         // The flags are called `-L` and `-F` both in Clang, ld64 and ldd.
-        let sdk_root = Path::new(&sdk_root);
-        cmd.include_path(&sdk_root.join("System/iOSSupport/usr/lib"));
-        cmd.framework_path(&sdk_root.join("System/iOSSupport/System/Library/Frameworks"));
+        // let sdk_root = Path::new(&sdk_root);
+        // cmd.include_path(&sdk_root.join("System/iOSSupport/usr/lib"));
+        // cmd.framework_path(&sdk_root.join("System/iOSSupport/System/Library/Frameworks"));
     }
 }
 

compiler/rustc_session/src/filesearch.rs

@@ -19,6 +19,11 @@ pub struct FileSearch<'a> {
 }
 
 impl<'a> FileSearch<'a> {
+    pub fn cli_search_paths(&self) -> impl Iterator<Item = &'a SearchPath> {
+        let kind = self.kind;
+        self.cli_search_paths.iter().filter(move |sp| sp.kind.matches(kind))
+    }
+
     pub fn search_paths(&self) -> impl Iterator<Item = &'a SearchPath> {
         let kind = self.kind;
         self.cli_search_paths