diff --git a/src/libfetchers/git.cc b/src/libfetchers/git.cc
index 2825b72ab..4a00d4e34 100644
--- a/src/libfetchers/git.cc
+++ b/src/libfetchers/git.cc
@@ -860,7 +860,7 @@ struct GitInputScheme : InputScheme
             return makeFingerprint(*rev);
         else {
             auto repoInfo = getRepoInfo(input);
-            if (auto repoPath = repoInfo.getPath(); repoPath && repoInfo.workdirInfo.headRev && repoInfo.workdirInfo.submodules.empty()) {
+            if (auto repoPath = repoInfo.getPath(); repoPath && repoInfo.workdirInfo.submodules.empty()) {
                 /* Calculate a fingerprint that takes into account the
                    deleted and modified/added files. */
                 HashSink hashSink{HashAlgorithm::SHA512};
@@ -873,7 +873,7 @@ struct GitInputScheme : InputScheme
                     writeString("deleted:", hashSink);
                     writeString(file.abs(), hashSink);
                 }
-                return makeFingerprint(*repoInfo.workdirInfo.headRev)
+                return makeFingerprint(repoInfo.workdirInfo.headRev.value_or(nullRev))
                     + ";d=" + hashSink.finish().first.to_string(HashFormat::Base16, false);
             }
             return std::nullopt;