Re: [BUG/PATCH] setup: Copy an environment variable to avoid overwrites

> It is possible for this pointer of the GIT_DIR environment variable to
> survive unduplicated until further getenv calls are made.  The standards
> allow for subsequent calls of getenv to overwrite the string located at
> its returned pointer, and this can result in broken git operations on
> certain platforms.
>
> Signed-off-by: David Michael <fedora.dm0@gmail.com>
> ---
>
> I have encountered an issue with consecutive calls to getenv
> overwriting earlier values.  Most notably, it prevents a plain "git
> clone" from working.
>
> Long story short: This value of GIT_DIR gets passed around setup.c
> until it reaches check_repository_format_gently.  This function calls
> git_config_early, which eventually runs getenv("HOME").  When it
> returns back to check_repository_format_gently, the gitdir variable
> contains my home directory path.  The end result is that I wind up
> with ~/objects/ etc. and a failed repository clone.  (Simply adding a
> bare getenv("GIT_DIR") afterwards to reset the pointer also corrects
> the problem.)
>
> Since other platforms are apparently working, yet this getenv behavior
> is supported by the standards, I am left wondering if this could be a
> symptom of something else being broken on my platform (z/OS).  Can
> anyone more familiar with this part of git identify any condition that
> obviously should not be occurring?
>
> Thanks.