[macos] GIT fatal: ambiguous argument 'HEAD': unknown revision or path not in the working tree

I'm trying to initialize a new GIT repo from Debian (actually a VM on Virtualbox, installed and running on Mac OS X) :

[david@server-VM-001:~ $] mkdir test
[david@server-VM-001:~ $] cd test
[david@server-VM-001:test $] git init
Initialized empty Git repository in /home/david/test/.git/
fatal: ambiguous argument 'HEAD': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions
[david@server-VM-001:test  (master #) $] 

What's the problem?

This question is related to macos git virtualbox

The answer is


Jacob Helwig mentions in his answer that:

It looks like rev-parse is being used without sufficient error checking before-hand

Commit 62f162f from Jeff King (peff) should improve the robustness of git rev-parse in Git 1.9/2.0 (Q1 2014) (in addition of commit 1418567):

For cases where we do not match (e.g., "doesnotexist..HEAD"), we would then want to try to treat the argument as a filename.
try_difference() gets this right, and always unmunges in this case.
However, try_parent_shorthand() never unmunges, leading to incorrect error messages, or even incorrect results:

$ git rev-parse foobar^@
foobar
fatal: ambiguous argument 'foobar': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'

As others pointed out, this message is coming from your shell prompt. The problem is that in a freshly created repository HEAD (.git/HEAD) points to a ref that doesn't exist yet.

% git init test
Initialized empty shared Git repository in /Users/jhelwig/tmp/test/.git/
% cd test
% cat .git/HEAD
ref: refs/heads/master
% ls -l .git/refs/heads
total 0
% git rev-parse HEAD
HEAD
fatal: ambiguous argument 'HEAD': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions

It looks like rev-parse is being used without sufficient error checking before-hand. After the first commit has been created .git/refs/heads looks a bit different and git rev-parse HEAD will no longer fail.

% ls -l .git/refs/heads
total 4
-rw------- 1 jhelwig staff 41 Oct 14 16:07 master
% git rev-parse HEAD
af0f70f8962f8b88eef679a1854991cb0f337f89

In the function that updates the Git information for the rest of my shell prompt (heavily modified version of wunjo prompt theme for ZSH), I have the following to get around this:

zgit_info_update() {
    zgit_info=()

    local gitdir=$(git rev-parse --git-dir 2>/dev/null)
    if [ $? -ne 0 ] || [ -z "$gitdir" ]; then
        return
    fi

    # More code ...
}

I usually use git on my linux machine, but at work I have to use Windows. I had the same problem when trying to commit the first commit in a Windows environment.

For those still facing this problem, I was able to resolve it as follows:

$ git commit --allow-empty -n -m "Initial commit".

I had same issue and I solved it by "pod setup" after installing cocoapods.


I had this issue when having a custom display in my terminal when creating a new git project (I have my branch display before the pathname e.g. :/current/path). All I needed to do was do my initial commit to my master branch to get this message to go away.


Examples related to macos

Problems with installation of Google App Engine SDK for php in OS X dyld: Library not loaded: /usr/local/opt/openssl/lib/libssl.1.0.0.dylib dyld: Library not loaded: /usr/local/opt/icu4c/lib/libicui18n.62.dylib error running php after installing node with brew on Mac Could not install packages due to an EnvironmentError: [Errno 13] How do I install Java on Mac OSX allowing version switching? Git is not working after macOS Update (xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools) Can't compile C program on a Mac after upgrade to Mojave You don't have write permissions for the /Library/Ruby/Gems/2.3.0 directory. (mac user) How can I install a previous version of Python 3 in macOS using homebrew? Could not install packages due to a "Environment error :[error 13]: permission denied : 'usr/local/bin/f2py'"

Examples related to git

Does the target directory for a git clone have to match the repo name? Git fatal: protocol 'https' is not supported Git is not working after macOS Update (xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools) git clone: Authentication failed for <URL> destination path already exists and is not an empty directory SSL_connect: SSL_ERROR_SYSCALL in connection to github.com:443 GitLab remote: HTTP Basic: Access denied and fatal Authentication How can I switch to another branch in git? VS 2017 Git Local Commit DB.lock error on every commit How to remove an unpushed outgoing commit in Visual Studio?

Examples related to virtualbox

virtualbox Raw-mode is unavailable courtesy of Hyper-V windows 10 VirtualBox Cannot register the hard disk already exists how to get the ipaddress of a virtual box running on local machine How to install Guest addition in Mac OS as guest and Windows machine as host How to connect to a docker container from outside the host (same network) [Windows] Failed to open/create the internal network Vagrant on Windows10 VT-x is disabled in the BIOS for both all CPU modes (VERR_VMX_MSR_ALL_VMX_DISABLED) VirtualBox: mount.vboxsf: mounting failed with the error: No such device Shared folder between MacOSX and Windows on Virtual Box Virtualbox shared folder permissions