test(trim-paths): exercise GDB on windows-gnu

tests/testsuite/profile_trim_paths.rs

@@ -611,7 +611,7 @@ mod object_works {
 }
 
 fn object_works_helper(split_debuginfo: &str, run: impl Fn(&std::path::Path) -> Vec<u8>) {
-    let registry_src = paths::home().join(".cargo/registry/src");
+    let registry_src = paths::home().join(".cargo").join("registry").join("src");
     let registry_src_bytes = registry_src.as_os_str().as_encoded_bytes();
     let rust_src = "/lib/rustc/src/rust".as_bytes();
 
@@ -644,23 +644,27 @@ fn object_works_helper(split_debuginfo: &str, run: impl Fn(&std::path::Path) ->
     let pkg_root = p.root();
     let pkg_root = pkg_root.as_os_str().as_encoded_bytes();
 
+    // Our baseline of which source roots are discoverable without object trimming.
     p.cargo("build").run();
 
     let bin_path = p.bin("foo");
     assert!(bin_path.is_file());
     let stdout = run(&bin_path);
-    // On windows-msvc every debuginfo is in pdb file, so can't find anything here.
+
+    // TODO: re-enable this check when rustc bootstrap disables remapping
+    // <https://github.com/rust-lang/cargo/pull/12625#discussion_r1371714791>
+    // assert!(memchr::memmem::find(&stdout, rust_src).is_some());
+
+    // `file!()` in `bar()` keeps untrimmed registry source in the executable
+    // even when debuginfo is separate.
+    assert!(memchr::memmem::find(&stdout, registry_src_bytes).is_some());
+
+    // The local package root occurs only in debuginfo in this fixture.
+    // MSVC puts that debuginfo in the PDB,
+    // while the other inspectors read embedded debuginfo.
     if cfg!(target_env = "msvc") {
-        // TODO: re-enable this check when rustc bootstrap disables remapping
-        // <https://github.com/rust-lang/cargo/pull/12625#discussion_r1371714791>
-        // assert!(memchr::memmem::find(&stdout, rust_src).is_some());
-        assert!(memchr::memmem::find(&stdout, registry_src_bytes).is_none());
         assert!(memchr::memmem::find(&stdout, pkg_root).is_none());
     } else {
-        // TODO: re-enable this check when rustc bootstrap disables remapping
-        // <https://github.com/rust-lang/cargo/pull/12625#discussion_r1371714791>
-        // assert!(memchr::memmem::find(&stdout, rust_src).is_some());
-        assert!(memchr::memmem::find(&stdout, registry_src_bytes).is_some());
         assert!(memchr::memmem::find(&stdout, pkg_root).is_some());
     }
     p.cargo("clean").run();
@@ -689,11 +693,17 @@ fn object_works_helper(split_debuginfo: &str, run: impl Fn(&std::path::Path) ->
     let bin_path = p.bin("foo");
     assert!(bin_path.is_file());
     let stdout = run(&bin_path);
+
+    // Original sysroot source root should be trimmed.
     assert!(memchr::memmem::find(&stdout, rust_src).is_none());
+
+    // Check line by line so macOS can exempt untrimmable `OSO` symbols.
     for line in stdout.split(|c| c == &b'\n') {
-        let registry = memchr::memmem::find(line, registry_src_bytes).is_none();
-        let local = memchr::memmem::find(line, pkg_root).is_none();
-        if registry && local {
+        // original registry source root was trimmed.
+        let registry_is_trimmed = memchr::memmem::find(line, registry_src_bytes).is_none();
+        // original project root was trimmed.
+        let local_is_trimmed = memchr::memmem::find(line, pkg_root).is_none();
+        if registry_is_trimmed && local_is_trimmed {
             continue;
         }