From: Johannes Schindelin <johannes.schindelin@xxxxxx> A very common assumption in Git's source code base is that offset_1st_component() returns either 0 for relative paths, or 1 for absolute paths that start with a slash. In other words, the return value is either 0 or points just after the dir separator. This assumption is not fulfilled when calling offset_1st_component() e.g. on UNC paths on Windows, e.g. "//my-server/my-share". In this case, offset_1st_component() returns the length of the entire string (which is correct, because stripping the last "component" would not result in a valid directory), yet the return value still does not point just after a dir separator. This assumption is most prominently seen in the setup_git_directory_gently_1() function, where we want to append a ".git" component and simply assume that there is already a dir separator. In the UNC example given above, this assumption is incorrect. As a consequence, Git will fail to handle a worktree at the top of a UNC share correctly. Let's fix this by adding a dir separator specifically for that case: we found that there is no first component in the path and it does not end in a dir separator? Then add it. This fixes https://github.com/git-for-windows/git/issues/1320 Signed-off-by: Johannes Schindelin <johannes.schindelin@xxxxxx> --- setup.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/setup.c b/setup.c index a803b3ade3..3d24de15dd 100644 --- a/setup.c +++ b/setup.c @@ -934,6 +934,12 @@ static enum discovery_result setup_git_directory_gently_1(struct strbuf *dir, if (ceil_offset < 0) ceil_offset = min_offset - 2; + if (min_offset && min_offset == dir->len && + !is_dir_sep(dir->buf[min_offset - 1])) { + strbuf_addch(dir, '/'); + min_offset++; + } + /* * Test in the following order (relative to the dir): * - .git (file containing "gitdir: <path>") -- gitgitgadget