@@ -53,6 +53,14 @@ Object queries continue through `object_data()` and the supported
 `Repository.try_find_header()`/`find_object()` APIs, with the existing large-object
 and diagnostic CLI fallbacks. Storage uses the existing `hash_object` dispatch.
 
+`Head.tracking_branch()` asks Git's `rev-parse --symbolic-full-name` to resolve
+local upstreams configured with `branch.<name>.remote=.`. GixPython does not
+expose the corresponding Git-compatible upstream configuration resolver; this
+path retains CLI. Without it, both released GitPython 3.2.1 and the initial
+adapter return an invalid remote reference, preventing angr 10.0.4.post1 from
+reporting a valid local tracking branch. A native replacement must expose Git's
+local-upstream resolution, including its validation and diagnostics.
+
 `IndexFile` queries immutable entry records; it does not retain a parsed index.
 The compatibility `entries` property projects those queries into a read-only
 snapshot keyed by path and stage, preserving readers in dlt and Renku. It uses
 
@@ -51,6 +51,10 @@ Git executable and safety
 API changes
 -----------
 
+* ``Head.tracking_branch()`` returns a local ``Head`` when Git configures the
+  current repository (``branch.<name>.remote=.``) as the upstream, instead of
+  constructing an invalid ``refs/remotes/./...`` reference. Git resolves the
+  upstream location; remote tracking branches retain their existing behavior.
 * ``GitCmdObjectDB`` no longer inherits ``LooseObjectDB``. Its object reads,
   writes, existence checks, and enumeration use Git, including packed objects.
   Precompressed input streams and custom object-output writers are unsupported.
 
@@ -202,16 +202,23 @@ def set_tracking_branch(self, remote_reference: Union["RemoteReference", None])
 
         return self
 
-    def tracking_branch(self) -> Union["RemoteReference", None]:
+    def tracking_branch(self) -> Union["RemoteReference", "Head", None]:
         """
         :return:
-            The remote reference we are tracking, or ``None`` if we are not a tracking
-            branch.
+            The remote reference or local head we are tracking, or ``None`` if we
+            are not a tracking branch.
         """
         from .remote import RemoteReference
 
         reader = self.config_reader()
         if reader.has_option(self.k_config_remote) and reader.has_option(self.k_config_remote_ref):
+            if reader.get_value(self.k_config_remote) == ".":
+                # Git resolves local-upstream configuration; do not construct a
+                # remote reference for the special local-repository selector.
+                path = self.repo.git._call_process_safe(
+                    "rev_parse", "--symbolic-full-name", f"{self.name}@{{upstream}}"
+                )
+                return Head(self.repo, path)
             ref = Head(
                 self.repo,
                 Head.to_full_path(strip_quotes(reader.get_value(self.k_config_remote_ref))),
 
@@ -10,6 +10,18 @@
 from test.lib.fixtures import fixture_repo
 
 
+@pytest.mark.parametrize("object_format", ["sha1", "sha256"])
+@pytest.mark.parametrize("ref_format", ["files", "reftable"])
+def test_local_tracking_branch_uses_gits_upstream_location(object_format, ref_format):
+    with fixture_repo("downstream-local-upstream.sh", object_format, ref_format) as repo:
+        upstream = repo.head.reference.tracking_branch()
+        assert isinstance(upstream, git.Head)
+        assert upstream.path == repo.git.rev_parse("--symbolic-full-name", "@{upstream}")
+        assert upstream.name == "upstream"
+        assert not upstream.is_remote()
+        assert upstream.commit == repo.head.commit
+
+
 @pytest.mark.parametrize("object_format", ["sha1", "sha256"])
 @pytest.mark.parametrize("ref_format", ["files", "reftable"])
 def test_legacy_gitdb_selector_uses_the_managed_object_backend(object_format, ref_format):
 
@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+set -eu
+git init -q --object-format="$1" --ref-format="$2" repo
+cd repo
+printf tracked > tracked
+git add tracked
+git commit -qm initial
+git branch upstream
+branch=$(git symbolic-ref --short HEAD)
+git config "branch.$branch.remote" .
+git config "branch.$branch.merge" refs/heads/upstream