fix(trim-paths): remove SO symbols for object scope

Even when when debuginfo is splitted,
`SO` debug symbols are still embedded in executables on macOS.
Therefore, we trim them when the scope of `object` is present,
as it is expected no path embedded in final executables
when `object` scope applied.

Author: weihanglo

compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs

@@ -846,14 +846,16 @@ pub fn build_compile_unit_di_node<'ll, 'tcx>(
     name_in_debuginfo.push("@");
     name_in_debuginfo.push(codegen_unit_name);
 
-    debug!("build_compile_unit_di_node: {:?}", name_in_debuginfo);
     let rustc_producer = format!("rustc version {}", tcx.sess.cfg_version);
     // FIXME(#41252) Remove "clang LLVM" if we can get GDB and LLVM to play nice.
     let producer = format!("clang LLVM ({rustc_producer})");
 
     use rustc_session::RemapFileNameExt;
     let name_in_debuginfo = name_in_debuginfo.to_string_lossy();
     let work_dir = tcx.sess.opts.working_dir.for_codegen(tcx.sess).to_string_lossy();
+    debug!(?work_dir, "build_compile_unit_di_node");
+    debug!(?name_in_debuginfo, "build_compile_unit_di_node");
+
     let flags = "\0";
     let output_filenames = tcx.output_filenames(());
     let split_name = if tcx.sess.target_can_use_split_dwarf() {

compiler/rustc_session/src/session.rs

@@ -1255,6 +1255,15 @@ impl Session {
             prefer_remapped |= has_split_debuginfo;
         }
 
+        if self.target.is_like_osx && remap_path_scopes.contains(RemapPathScopeComponents::OBJECT) {
+            // HACK: Even when when debuginfo is splitted,
+            // `SO` debug symbols are still embedded in executables on macOS.
+            // Therefore, we trim them when the scope of `object` is present,
+            // as it is expected no path embedded in final executables
+            // when `object` scope applied.
+            prefer_remapped |= true;
+        }
+
         prefer_remapped
     }
 

tests/run-make/split-debuginfo/Makefile

@@ -24,7 +24,7 @@ packed-remapped-scope:
 		-Z remap-path-scope=object foo.rs -g
 	ls $(TMPDIR)/*.o && exit 1 || exit 0
 	[ -d $(TMPDIR)/foo.dSYM ]
-	dsymutil -s $(TMPDIR)/foo | grep 'N_SO' | grep $(HERE) || exit 1 # expected behavior is (! grep ...)
+	dsymutil -s $(TMPDIR)/foo | grep 'N_SO' | (! grep $(HERE)) || exit 1
 	# As of 2023-12, `OSO` should be the only thing that cannot be trimmed. See rust-lang/rust#116948
 	dsymutil -s $(TMPDIR)/foo | grep 'N_OSO' | grep $(TMPDIR) || exit 1 # expected behavior is (! grep ...)
 	rm -rf $(TMPDIR)/foo.dSYM
@@ -56,7 +56,7 @@ unpacked-remapped-scope:
 		-Z remap-path-scope=object foo.rs -g
 	ls $(TMPDIR)/*.o
 	[ ! -d $(TMPDIR)/foo.dSYM ]
-	dsymutil -s $(TMPDIR)/foo | grep 'N_SO' | (grep $(HERE)) || exit 1 # expected behavior is (! grep ...)
+	dsymutil -s $(TMPDIR)/foo | grep 'N_SO' | (! grep $(HERE)) || exit 1
 	# As of 2023-12, `OSO` should be the only thing that cannot be trimmed. See rust-lang/rust#116948
 	dsymutil -s $(TMPDIR)/foo | grep 'N_OSO' | (grep $(TMPDIR)) || exit 1 # expected behavior is (! grep ...)
 	rm $(TMPDIR)/*.o