clone: do not export and unexport GIT_CONFIG

Earlier, dc87183 (use GIT_CONFIG only in "git config", not other
programs, 2008-06-30) made sure that the environment variable is
never used outside "git config", but "git clone", after creating a
directory for the new repository and until the init_db() function
populates its .git/ directory, exported the variable for no good
reason.  No hook will run from init_db() and more importantly no
hook can run until init_db() finishes creation of the new
repository, so it cannot be used by any invocation of "git config"
by definition.

Stop doing the useless export/unexport.

Signed-off-by: Junio C Hamano <[email protected]>

Author: gitster

builtin/clone.c

@@ -714,8 +714,6 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 	atexit(remove_junk);
 	sigchain_push_common(remove_junk_on_signal);
 
-	setenv(CONFIG_ENVIRONMENT, mkpath("%s/config", git_dir), 1);
-
 	if (safe_create_leading_directories_const(git_dir) < 0)
 		die(_("could not create leading directories of '%s'"), git_dir);
 
@@ -732,13 +730,6 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 	init_db(option_template, INIT_DB_QUIET);
 	write_config(&option_config);
 
-	/*
-	 * At this point, the config exists, so we do not need the
-	 * environment variable.  We actually need to unset it, too, to
-	 * re-enable parsing of the global configs.
-	 */
-	unsetenv(CONFIG_ENVIRONMENT);
-
 	git_config(git_default_config, NULL);
 
 	if (option_bare) {