Thank you for filling out a Git bug report! Please answer the following questions to help us understand your issue. What did you do before the bug happened? (Steps to reproduce your issue) Checked out a branch, ran "git diff --merge-base <some-annotated-tag> HEAD". What did you expect to happen? (Expected behavior) To see a normal git diff output. What happened instead? (Actual behavior) Didn't get a diff output. Got the following error instead: "fatal: --merge-base only works with commits" What's different between what you expected and what actually happened? I didn't get the expected diff output and got an error message instead. Anything else you want to add: Seems it happens when I use a tag as one of the commits for git diff --merge-base. This is on a macOS, with apple git. On Windows, with Git Bash, it works as expected. I can get this to work with "git diff --merge-base $(git rev-list -n 1 <some-annotated-tag>) HEAD". Please review the rest of the bug report below. You can delete any lines you don't wish to share. [System Info] git version: git version 2.39.5 (Apple Git-154) cpu: arm64 no commit associated with this build sizeof-long: 8 sizeof-size_t: 8 shell-path: /bin/sh feature: fsmonitor--daemon uname: Darwin 24.2.0 Darwin Kernel Version 24.2.0: Fri Dec 6 18:56:34 PST 2024; root:xnu-11215.61.5~2/RELEASE_ARM64_T6020 arm64 compiler info: clang: 16.0.0 (clang-1600.0.26.6) libc info: no libc information available $SHELL (typically, interactive shell): /bin/zsh [Enabled Hooks] pre-push
