diff --git a/lib/util/git/index.ts b/lib/util/git/index.ts
index df39eb8be2301513e18c2ba3a580b9767d99e079..78e212a4f8ff1e3dd6c8399da10f5128693e0d31 100644
--- a/lib/util/git/index.ts
+++ b/lib/util/git/index.ts
@@ -498,6 +498,7 @@ export async function getBranchFiles(branchName: string): Promise<string[]> {
     const diff = await git.diffSummary([branchName, config.currentBranch]);
     return diff.files.map((file) => file.file);
   } catch (err) /* istanbul ignore next */ {
+    logger.warn({ err }, 'getBranchFiles error');
     checkForPlatformFailure(err);
     return null;
   }