diff --git a/git.c b/git.c
index d7b5f88e52..2d27ad4175 100644
--- a/git.c
+++ b/git.c
@@ -571,11 +571,11 @@ static struct cmd_struct commands[] = {
 	{ "diff", cmd_diff, NO_PARSEOPT },
 	{ "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 	{ "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
-	{ "diff-pairs", cmd_diff_pairs, RUN_SETUP | NO_PARSEOPT },
+	{ "diff-pairs", cmd_diff_pairs, RUN_SETUP },
 	{ "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
 	{ "difftool", cmd_difftool, RUN_SETUP_GENTLY },
 	{ "fast-export", cmd_fast_export, RUN_SETUP },
-	{ "fast-import", cmd_fast_import, RUN_SETUP | NO_PARSEOPT },
+	{ "fast-import", cmd_fast_import, RUN_SETUP },
 	{ "fetch", cmd_fetch, RUN_SETUP },
 	{ "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
 	{ "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
@@ -626,7 +626,7 @@ static struct cmd_struct commands[] = {
 	{ "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT | DEPRECATED },
 #endif
 	{ "pack-refs", cmd_pack_refs, RUN_SETUP },
-	{ "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
+	{ "patch-id", cmd_patch_id, RUN_SETUP_GENTLY },
 	{ "pickaxe", cmd_blame, RUN_SETUP },
 	{ "prune", cmd_prune, RUN_SETUP },
 	{ "prune-packed", cmd_prune_packed, RUN_SETUP },
@@ -676,7 +676,7 @@ static struct cmd_struct commands[] = {
 	{ "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
 	{ "upload-pack", cmd_upload_pack },
 	{ "url-parse", cmd_url_parse },
-	{ "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
+	{ "var", cmd_var, RUN_SETUP_GENTLY },
 	{ "verify-commit", cmd_verify_commit, RUN_SETUP },
 	{ "verify-pack", cmd_verify_pack },
 	{ "verify-tag", cmd_verify_tag, RUN_SETUP },
diff --git a/parse-options.c b/parse-options.c
index e6c2e4595d..58e9fb17f4 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -1745,6 +1745,12 @@ void show_usage_with_options_if_asked(int ac, const char **av,
 			usage_with_options_internal(NULL, usagestr, opts,
 						    USAGE_FULL, USAGE_TO_STDOUT);
 			exit(0);
+		} else if (!strcmp(av[1], "--git-completion-helper")) {
+			show_gitcomp(opts, 0);
+			exit(0);
+		} else if (!strcmp(av[1], "--git-completion-helper-all")) {
+			show_gitcomp(opts, 1);
+			exit(0);
 		}
 	}
 }
diff --git a/parse-options.h b/parse-options.h
index eb653980c6..63186eb15a 100644
--- a/parse-options.h
+++ b/parse-options.h
@@ -439,6 +439,12 @@ int parse_options_takes_argument(const struct option *opt);
 NORETURN void usage_with_options(const char * const *usagestr,
 				 const struct option *options);
 
+/*
+ * Programs that call parse_options() early do not need this function.
+ * If your program has to answer help requests (-h and --help-all) or
+ * the completion helper before parse_options() runs, call this
+ * function to answer them.
+ */
 void show_usage_with_options_if_asked(int ac, const char **av,
 				      const char * const *usage,
 				      const struct option *options);
diff --git a/t/t0012-help.sh b/t/t0012-help.sh
index b0a3fdbbbc..41197c67e2 100755
--- a/t/t0012-help.sh
+++ b/t/t0012-help.sh
@@ -267,4 +267,29 @@ do
 	'
 done <builtins
 
+test_expect_success 'generate list of builtins without parse-options' '
+	git --list-cmds=parseopt >parseopt &&
+	tr " " "\n" <parseopt | sort >sorted-parseopt &&
+	sort builtins >sorted-builtins &&
+	comm -23 sorted-builtins sorted-parseopt >no-parseopt
+'
+
+while read builtin
+do
+	case "$builtin" in
+	# these answer with the diff options
+	diff|diff-files|diff-index|diff-tree|rev-list)
+		continue ;;
+	# rev-parse prints unknown arguments back
+	rev-parse)
+		continue ;;
+	esac
+
+	test_expect_success "$builtin does not answer --git-completion-helper" '
+		test_might_fail git $builtin --git-completion-helper \
+			</dev/null >output 2>/dev/null &&
+		test_grep ! "^--" output
+	'
+done <no-parseopt
+
 test_done
diff --git a/t/t9300-fast-import.sh b/t/t9300-fast-import.sh
index 1c6685dc90..3ba6ae0cb3 100755
--- a/t/t9300-fast-import.sh
+++ b/t/t9300-fast-import.sh
@@ -2950,6 +2950,22 @@ test_expect_success 'R: blob appears only once' '
 	test 1 = $n
 '
 
+test_expect_success 'R: --git-completion-helper does not read from stdin' '
+	find .git/objects/pack -name "tmp_pack_*" >before &&
+	echo garbage | git fast-import --git-completion-helper >out &&
+	test_grep -e "--date-format=" out &&
+	find .git/objects/pack -name "tmp_pack_*" >after &&
+	test_cmp before after
+'
+
+test_expect_success 'R: --git-completion-helper-all does not read from stdin' '
+	find .git/objects/pack -name "tmp_pack_*" >before &&
+	echo garbage | git fast-import --git-completion-helper-all >all &&
+	test_grep -e "--allow-unsafe-features" all &&
+	find .git/objects/pack -name "tmp_pack_*" >after &&
+	test_cmp before after
+'
+
 ###
 ### series S (mark and path parsing)
 ###