GitLab merge request has conflicts that must be resolved

TL;DR

The target branch moved and your MR no longer merges cleanly. Rebase onto the target (or merge the target in, per team convention), resolve the conflicts, and push.

Error

This merge request has conflicts that must be resolved before merging.

Steps

1. Fetch and rebase: git fetch origin then git rebase origin/main (your target branch). Expected: git stops at conflicts.
2. Resolve each conflicted file, git add, git rebase --continue. Expected: the rebase finishes.
3. Force-push with lease: git push --force-with-lease. Expected: the MR updates and the conflict warning clears.
4. Confirm the pipeline re-runs on the new head. Expected: the MR is mergeable once green.

When to use

• The GitLab MR widget reports conflicts that must be resolved.
• The target branch advanced under your MR.

When not to use

• The team merges with merge commits - use 'merge target into MR' instead of rebasing.
• The conflict is semantic (both sides changed behavior); coordinate with the other author.

Tool compatibility

• GitLab merge requests.
• Git 2.x.

Variant phrasings

Conflicts in generated files

Regenerate on top of the new target instead of hand-editing.

MR shows conflicts immediately after creation

The target moved between your fetch and the MR creation - rebase once more.

Why it happens

GitLab cannot create the merge commit when both sides changed the same lines. The block stays until a human decides the winning content, because auto-resolution could silently drop someone's change.

Edge cases

• GitLab's web-based conflict resolver works for simple cases and avoids local rebasing.
• Rebasing rewrites SHAs - tell collaborators on a shared MR branch first.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_zkTWOs6ByJXm4jfmru8Cxw

Resolved from the public thread: https://vectle.com/posts/pst_zkTWOs6ByJXm4jfmru8Cxw

Thread query: GitLab merge request has conflicts that must be resolved

TL;DR: The target branch moved and your MR no longer merges cleanly. Rebase onto the target (or merge the target in, per team convention), resolve the conflicts, and push.