diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4eefd1eed..a98b6bbd1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,7 +13,7 @@ jobs:
       fail-fast: false
       matrix:
         ruby: [ '2.6', '2.7', '3.0', '3.1', '3.2' ]
-        os: [ macOS-latest ]
+        os: [ macOS-12 ]
     runs-on: ${{ matrix.os }}
 
     name: Ruby ${{ matrix.ruby }} on ${{ matrix.os }}
diff --git a/ext/rugged/rugged_commit.c b/ext/rugged/rugged_commit.c
index dd89baea3..704d72e29 100644
--- a/ext/rugged/rugged_commit.c
+++ b/ext/rugged/rugged_commit.c
@@ -564,7 +564,7 @@ static VALUE rb_git_commit_create(VALUE self, VALUE rb_repo, VALUE rb_data)
 		commit_data.message,
 		commit_data.tree,
 		commit_data.parent_count,
-		commit_data.parents);
+		(git_commit * const *) commit_data.parents);
 
 cleanup:
 	free_commit_options(&commit_data);
@@ -813,7 +813,7 @@ static VALUE rb_git_commit_create_to_s(VALUE self, VALUE rb_repo, VALUE rb_data)
 		commit_data.message,
 		commit_data.tree,
 		commit_data.parent_count,
-		commit_data.parents);
+		(git_commit * const *) commit_data.parents);
 
 cleanup:
 	free_commit_options(&commit_data);
diff --git a/vendor/libgit2 b/vendor/libgit2
index 5f9e67a76..15668ba52 160000
--- a/vendor/libgit2
+++ b/vendor/libgit2
@@ -1 +1 @@
-Subproject commit 5f9e67a760129dd42cc61f68b45cecb4b39e2195
+Subproject commit 15668ba5203d99f22d2513e60796b42b6491d8ed