merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 167 insertions, 86 deletions

diff --git a/third_party/git/bisect.c b/third_party/git/bisect.c
index e87ac29a51be..f5b13681288c 100644
--- a/third_party/git/bisect.c
+++ b/third_party/git/bisect.c
@@ -10,11 +10,12 @@
 #include "run-command.h"
 #include "log-tree.h"
 #include "bisect.h"
-#include "sha1-array.h"
-#include "argv-array.h"
+#include "oid-array.h"
+#include "strvec.h"
 #include "commit-slab.h"
 #include "commit-reach.h"
 #include "object-store.h"
+#include "dir.h"
 
 static struct oid_array good_revs;
 static struct oid_array skipped_revs;
@@ -88,15 +89,16 @@ static inline void weight_set(struct commit_list *elem, int weight)
 	**commit_weight_at(&commit_weight, elem->item) = weight;
 }
 
-static int count_interesting_parents(struct commit *commit)
+static int count_interesting_parents(struct commit *commit, unsigned bisect_flags)
 {
 	struct commit_list *p;
 	int count;
 
 	for (count = 0, p = commit->parents; p; p = p->next) {
-		if (p->item->object.flags & UNINTERESTING)
-			continue;
-		count++;
+		if (!(p->item->object.flags & UNINTERESTING))
+			count++;
+		if (bisect_flags & FIND_BISECTION_FIRST_PARENT_ONLY)
+			break;
 	}
 	return count;
 }
@@ -135,7 +137,7 @@ static void show_list(const char *debug, int counted, int nr,
 	for (p = list; p; p = p->next) {
 		struct commit_list *pp;
 		struct commit *commit = p->item;
-		unsigned flags = commit->object.flags;
+		unsigned commit_flags = commit->object.flags;
 		enum object_type type;
 		unsigned long size;
 		char *buf = read_object_file(&commit->object.oid, &type,
@@ -144,9 +146,9 @@ static void show_list(const char *debug, int counted, int nr,
 		int subject_len;
 
 		fprintf(stderr, "%c%c%c ",
-			(flags & TREESAME) ? ' ' : 'T',
-			(flags & UNINTERESTING) ? 'U' : ' ',
-			(flags & COUNTED) ? 'C' : ' ');
+			(commit_flags & TREESAME) ? ' ' : 'T',
+			(commit_flags & UNINTERESTING) ? 'U' : ' ',
+			(commit_flags & COUNTED) ? 'C' : ' ');
 		if (*commit_weight_at(&commit_weight, p->item))
 			fprintf(stderr, "%3d", weight(p));
 		else
@@ -171,9 +173,9 @@ static struct commit_list *best_bisection(struct commit_list *list, int nr)
 	best = list;
 	for (p = list; p; p = p->next) {
 		int distance;
-		unsigned flags = p->item->object.flags;
+		unsigned commit_flags = p->item->object.flags;
 
-		if (flags & TREESAME)
+		if (commit_flags & TREESAME)
 			continue;
 		distance = weight(p);
 		if (nr - distance < distance)
@@ -212,9 +214,9 @@ static struct commit_list *best_bisection_sorted(struct commit_list *list, int n
 
 	for (p = list, cnt = 0; p; p = p->next) {
 		int distance;
-		unsigned flags = p->item->object.flags;
+		unsigned commit_flags = p->item->object.flags;
 
-		if (flags & TREESAME)
+		if (commit_flags & TREESAME)
 			continue;
 		distance = weight(p);
 		if (nr - distance < distance)
@@ -259,7 +261,7 @@ static struct commit_list *best_bisection_sorted(struct commit_list *list, int n
  */
 static struct commit_list *do_find_bisection(struct commit_list *list,
 					     int nr, int *weights,
-					     int find_all)
+					     unsigned bisect_flags)
 {
 	int n, counted;
 	struct commit_list *p;
@@ -268,12 +270,12 @@ static struct commit_list *do_find_bisection(struct commit_list *list,
 
 	for (n = 0, p = list; p; p = p->next) {
 		struct commit *commit = p->item;
-		unsigned flags = commit->object.flags;
+		unsigned commit_flags = commit->object.flags;
 
 		*commit_weight_at(&commit_weight, p->item) = &weights[n++];
-		switch (count_interesting_parents(commit)) {
+		switch (count_interesting_parents(commit, bisect_flags)) {
 		case 0:
-			if (!(flags & TREESAME)) {
+			if (!(commit_flags & TREESAME)) {
 				weight_set(p, 1);
 				counted++;
 				show_list("bisection 2 count one",
@@ -314,11 +316,13 @@ static struct commit_list *do_find_bisection(struct commit_list *list,
 			continue;
 		if (weight(p) != -2)
 			continue;
+		if (bisect_flags & FIND_BISECTION_FIRST_PARENT_ONLY)
+			BUG("shouldn't be calling count-distance in fp mode");
 		weight_set(p, count_distance(p));
 		clear_distance(list);
 
 		/* Does it happen to be at exactly half-way? */
-		if (!find_all && halfway(p, nr))
+		if (!(bisect_flags & FIND_BISECTION_ALL) && halfway(p, nr))
 			return p;
 		counted++;
 	}
@@ -328,11 +332,14 @@ static struct commit_list *do_find_bisection(struct commit_list *list,
 	while (counted < nr) {
 		for (p = list; p; p = p->next) {
 			struct commit_list *q;
-			unsigned flags = p->item->object.flags;
+			unsigned commit_flags = p->item->object.flags;
 
 			if (0 <= weight(p))
 				continue;
-			for (q = p->item->parents; q; q = q->next) {
+
+			for (q = p->item->parents;
+			     q;
+			     q = bisect_flags & FIND_BISECTION_FIRST_PARENT_ONLY ? NULL : q->next) {
 				if (q->item->object.flags & UNINTERESTING)
 					continue;
 				if (0 <= weight(q))
@@ -346,7 +353,7 @@ static struct commit_list *do_find_bisection(struct commit_list *list,
 			 * add one for p itself if p is to be counted,
 			 * otherwise inherit it from q directly.
 			 */
-			if (!(flags & TREESAME)) {
+			if (!(commit_flags & TREESAME)) {
 				weight_set(p, weight(q)+1);
 				counted++;
 				show_list("bisection 2 count one",
@@ -356,21 +363,21 @@ static struct commit_list *do_find_bisection(struct commit_list *list,
 				weight_set(p, weight(q));
 
 			/* Does it happen to be at exactly half-way? */
-			if (!find_all && halfway(p, nr))
+			if (!(bisect_flags & FIND_BISECTION_ALL) && halfway(p, nr))
 				return p;
 		}
 	}
 
 	show_list("bisection 2 counted all", counted, nr, list);
 
-	if (!find_all)
+	if (!(bisect_flags & FIND_BISECTION_ALL))
 		return best_bisection(list, nr);
 	else
 		return best_bisection_sorted(list, nr);
 }
 
 void find_bisection(struct commit_list **commit_list, int *reaches,
-		    int *all, int find_all)
+		    int *all, unsigned bisect_flags)
 {
 	int nr, on_list;
 	struct commit_list *list, *p, *best, *next, *last;
@@ -386,16 +393,16 @@ void find_bisection(struct commit_list **commit_list, int *reaches,
 	for (nr = on_list = 0, last = NULL, p = *commit_list;
 	     p;
 	     p = next) {
-		unsigned flags = p->item->object.flags;
+		unsigned commit_flags = p->item->object.flags;
 
 		next = p->next;
-		if (flags & UNINTERESTING) {
+		if (commit_flags & UNINTERESTING) {
 			free(p);
 			continue;
 		}
 		p->next = last;
 		last = p;
-		if (!(flags & TREESAME))
+		if (!(commit_flags & TREESAME))
 			nr++;
 		on_list++;
 	}
@@ -406,9 +413,9 @@ void find_bisection(struct commit_list **commit_list, int *reaches,
 	weights = xcalloc(on_list, sizeof(*weights));
 
 	/* Do the real work of finding bisection commit. */
-	best = do_find_bisection(list, nr, weights, find_all);
+	best = do_find_bisection(list, nr, weights, bisect_flags);
 	if (best) {
-		if (!find_all) {
+		if (!(bisect_flags & FIND_BISECTION_ALL)) {
 			list->item = best->item;
 			free_commit_list(list->next);
 			best = list;
@@ -454,9 +461,10 @@ static GIT_PATH_FUNC(git_path_bisect_run, "BISECT_RUN")
 static GIT_PATH_FUNC(git_path_bisect_start, "BISECT_START")
 static GIT_PATH_FUNC(git_path_bisect_log, "BISECT_LOG")
 static GIT_PATH_FUNC(git_path_bisect_terms, "BISECT_TERMS")
+static GIT_PATH_FUNC(git_path_bisect_first_parent, "BISECT_FIRST_PARENT")
 static GIT_PATH_FUNC(git_path_head_name, "head-name")
 
-static void read_bisect_paths(struct argv_array *array)
+static void read_bisect_paths(struct strvec *array)
 {
 	struct strbuf str = STRBUF_INIT;
 	const char *filename = git_path_bisect_names();
@@ -464,7 +472,7 @@ static void read_bisect_paths(struct argv_array *array)
 
 	while (strbuf_getline_lf(&str, fp) != EOF) {
 		strbuf_trim(&str);
-		if (sq_dequote_to_argv_array(str.buf, array))
+		if (sq_dequote_to_strvec(str.buf, array))
 			die(_("Badly quoted content in file '%s': %s"),
 			    filename, str.buf);
 	}
@@ -473,7 +481,7 @@ static void read_bisect_paths(struct argv_array *array)
 	fclose(fp);
 }
 
-static char *join_sha1_array_hex(struct oid_array *array, char delim)
+static char *join_oid_array_hex(struct oid_array *array, char delim)
 {
 	struct strbuf joined_hexs = STRBUF_INIT;
 	int i;
@@ -572,7 +580,7 @@ static int sqrti(int val)
 {
 	float d, x = val;
 
-	if (val == 0)
+	if (!val)
 		return 0;
 
 	do {
@@ -632,7 +640,7 @@ static void bisect_rev_setup(struct repository *r, struct rev_info *revs,
 			     const char *bad_format, const char *good_format,
 			     int read_paths)
 {
-	struct argv_array rev_argv = ARGV_ARRAY_INIT;
+	struct strvec rev_argv = STRVEC_INIT;
 	int i;
 
 	repo_init_revisions(r, revs, prefix);
@@ -640,16 +648,16 @@ static void bisect_rev_setup(struct repository *r, struct rev_info *revs,
 	revs->commit_format = CMIT_FMT_UNSPECIFIED;
 
 	/* rev_argv.argv[0] will be ignored by setup_revisions */
-	argv_array_push(&rev_argv, "bisect_rev_setup");
-	argv_array_pushf(&rev_argv, bad_format, oid_to_hex(current_bad_oid));
+	strvec_push(&rev_argv, "bisect_rev_setup");
+	strvec_pushf(&rev_argv, bad_format, oid_to_hex(current_bad_oid));
 	for (i = 0; i < good_revs.nr; i++)
-		argv_array_pushf(&rev_argv, good_format,
-				 oid_to_hex(good_revs.oid + i));
-	argv_array_push(&rev_argv, "--");
+		strvec_pushf(&rev_argv, good_format,
+			     oid_to_hex(good_revs.oid + i));
+	strvec_push(&rev_argv, "--");
 	if (read_paths)
 		read_bisect_paths(&rev_argv);
 
-	setup_revisions(rev_argv.argc, rev_argv.argv, revs, NULL);
+	setup_revisions(rev_argv.nr, rev_argv.v, revs, NULL);
 	/* XXX leak rev_argv, as "revs" may still be pointing to it */
 }
 
@@ -661,11 +669,11 @@ static void bisect_common(struct rev_info *revs)
 		mark_edges_uninteresting(revs, NULL, 0);
 }
 
-static void exit_if_skipped_commits(struct commit_list *tried,
+static enum bisect_error error_if_skipped_commits(struct commit_list *tried,
 				    const struct object_id *bad)
 {
 	if (!tried)
-		return;
+		return BISECT_OK;
 
 	printf("There are only 'skip'ped commits left to test.\n"
 	       "The first %s commit could be any of:\n", term_bad);
@@ -676,7 +684,8 @@ static void exit_if_skipped_commits(struct commit_list *tried,
 	if (bad)
 		printf("%s\n", oid_to_hex(bad));
 	printf(_("We cannot bisect more!\n"));
-	exit(2);
+
+	return BISECT_ONLY_SKIPPED_LEFT;
 }
 
 static int is_expected_rev(const struct object_id *oid)
@@ -703,11 +712,12 @@ static int is_expected_rev(const struct object_id *oid)
 	return res;
 }
 
-static int bisect_checkout(const struct object_id *bisect_rev, int no_checkout)
+static enum bisect_error bisect_checkout(const struct object_id *bisect_rev, int no_checkout)
 {
 	char bisect_rev_hex[GIT_MAX_HEXSZ + 1];
+	enum bisect_error res = BISECT_OK;
 
-	memcpy(bisect_rev_hex, oid_to_hex(bisect_rev), GIT_SHA1_HEXSZ + 1);
+	oid_to_hex_r(bisect_rev_hex, bisect_rev);
 	update_ref(NULL, "BISECT_EXPECTED_REV", bisect_rev, NULL, 0, UPDATE_REFS_DIE_ON_ERR);
 
 	argv_checkout[2] = bisect_rev_hex;
@@ -715,14 +725,24 @@ static int bisect_checkout(const struct object_id *bisect_rev, int no_checkout)
 		update_ref(NULL, "BISECT_HEAD", bisect_rev, NULL, 0,
 			   UPDATE_REFS_DIE_ON_ERR);
 	} else {
-		int res;
 		res = run_command_v_opt(argv_checkout, RUN_GIT_CMD);
 		if (res)
-			exit(res);
+			/*
+			 * Errors in `run_command()` itself, signaled by res < 0,
+			 * and errors in the child process, signaled by res > 0
+			 * can both be treated as regular BISECT_FAILURE (-1).
+			 */
+			return -abs(res);
 	}
 
 	argv_show_branch[1] = bisect_rev_hex;
-	return run_command_v_opt(argv_show_branch, RUN_GIT_CMD);
+	res = run_command_v_opt(argv_show_branch, RUN_GIT_CMD);
+	/*
+	 * Errors in `run_command()` itself, signaled by res < 0,
+	 * and errors in the child process, signaled by res > 0
+	 * can both be treated as regular BISECT_FAILURE (-1).
+	 */
+	return -abs(res);
 }
 
 static struct commit *get_commit_reference(struct repository *r,
@@ -749,11 +769,11 @@ static struct commit **get_bad_and_good_commits(struct repository *r,
 	return rev;
 }
 
-static void handle_bad_merge_base(void)
+static enum bisect_error handle_bad_merge_base(void)
 {
 	if (is_expected_rev(current_bad_oid)) {
 		char *bad_hex = oid_to_hex(current_bad_oid);
-		char *good_hex = join_sha1_array_hex(&good_revs, ' ');
+		char *good_hex = join_oid_array_hex(&good_revs, ' ');
 		if (!strcmp(term_bad, "bad") && !strcmp(term_good, "good")) {
 			fprintf(stderr, _("The merge base %s is bad.\n"
 				"This means the bug has been fixed "
@@ -770,21 +790,21 @@ static void handle_bad_merge_base(void)
 				"between %s and [%s].\n"),
 				bad_hex, term_bad, term_good, bad_hex, good_hex);
 		}
-		exit(3);
+		return BISECT_MERGE_BASE_CHECK;
 	}
 
 	fprintf(stderr, _("Some %s revs are not ancestors of the %s rev.\n"
 		"git bisect cannot work properly in this case.\n"
 		"Maybe you mistook %s and %s revs?\n"),
 		term_good, term_bad, term_good, term_bad);
-	exit(1);
+	return BISECT_FAILED;
 }
 
 static void handle_skipped_merge_base(const struct object_id *mb)
 {
 	char *mb_hex = oid_to_hex(mb);
 	char *bad_hex = oid_to_hex(current_bad_oid);
-	char *good_hex = join_sha1_array_hex(&good_revs, ' ');
+	char *good_hex = join_oid_array_hex(&good_revs, ' ');
 
 	warning(_("the merge base between %s and [%s] "
 		"must be skipped.\n"
@@ -799,13 +819,18 @@ static void handle_skipped_merge_base(const struct object_id *mb)
  * "check_merge_bases" checks that merge bases are not "bad" (or "new").
  *
  * - If one is "bad" (or "new"), it means the user assumed something wrong
- * and we must exit with a non 0 error code.
+ * and we must return error with a non 0 error code.
  * - If one is "good" (or "old"), that's good, we have nothing to do.
  * - If one is "skipped", we can't know but we should warn.
  * - If we don't know, we should check it out and ask the user to test.
+ * - If a merge base must be tested, on success return
+ * BISECT_INTERNAL_SUCCESS_MERGE_BASE (-11) a special condition
+ * for early success, this will be converted back to 0 in
+ * check_good_are_ancestors_of_bad().
  */
-static void check_merge_bases(int rev_nr, struct commit **rev, int no_checkout)
+static enum bisect_error check_merge_bases(int rev_nr, struct commit **rev, int no_checkout)
 {
+	enum bisect_error res = BISECT_OK;
 	struct commit_list *result;
 
 	result = get_merge_bases_many(rev[0], rev_nr - 1, rev + 1);
@@ -813,18 +838,24 @@ static void check_merge_bases(int rev_nr, struct commit **rev, int no_checkout)
 	for (; result; result = result->next) {
 		const struct object_id *mb = &result->item->object.oid;
 		if (oideq(mb, current_bad_oid)) {
-			handle_bad_merge_base();
+			res = handle_bad_merge_base();
+			break;
 		} else if (0 <= oid_array_lookup(&good_revs, mb)) {
 			continue;
 		} else if (0 <= oid_array_lookup(&skipped_revs, mb)) {
 			handle_skipped_merge_base(mb);
 		} else {
 			printf(_("Bisecting: a merge base must be tested\n"));
-			exit(bisect_checkout(mb, no_checkout));
+			res = bisect_checkout(mb, no_checkout);
+			if (!res)
+				/* indicate early success */
+				res = BISECT_INTERNAL_SUCCESS_MERGE_BASE;
+			break;
 		}
 	}
 
 	free_commit_list(result);
+	return res;
 }
 
 static int check_ancestors(struct repository *r, int rev_nr,
@@ -850,43 +881,58 @@ static int check_ancestors(struct repository *r, int rev_nr,
  *
  * If that's not the case, we need to check the merge bases.
  * If a merge base must be tested by the user, its source code will be
- * checked out to be tested by the user and we will exit.
+ * checked out to be tested by the user and we will return.
  */
-static void check_good_are_ancestors_of_bad(struct repository *r,
+
+static enum bisect_error check_good_are_ancestors_of_bad(struct repository *r,
 					    const char *prefix,
 					    int no_checkout)
 {
-	char *filename = git_pathdup("BISECT_ANCESTORS_OK");
+	char *filename;
 	struct stat st;
 	int fd, rev_nr;
+	enum bisect_error res = BISECT_OK;
 	struct commit **rev;
 
 	if (!current_bad_oid)
-		die(_("a %s revision is needed"), term_bad);
+		return error(_("a %s revision is needed"), term_bad);
+
+	filename = git_pathdup("BISECT_ANCESTORS_OK");
 
 	/* Check if file BISECT_ANCESTORS_OK exists. */
 	if (!stat(filename, &st) && S_ISREG(st.st_mode))
 		goto done;
 
 	/* Bisecting with no good rev is ok. */
-	if (good_revs.nr == 0)
+	if (!good_revs.nr)
 		goto done;
 
 	/* Check if all good revs are ancestor of the bad rev. */
+
 	rev = get_bad_and_good_commits(r, &rev_nr);
 	if (check_ancestors(r, rev_nr, rev, prefix))
-		check_merge_bases(rev_nr, rev, no_checkout);
+		res = check_merge_bases(rev_nr, rev, no_checkout);
 	free(rev);
 
-	/* Create file BISECT_ANCESTORS_OK. */
-	fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY, 0600);
-	if (fd < 0)
-		warning_errno(_("could not create file '%s'"),
-			      filename);
-	else
-		close(fd);
+	if (!res) {
+		/* Create file BISECT_ANCESTORS_OK. */
+		fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY, 0600);
+		if (fd < 0)
+			/*
+			 * BISECT_ANCESTORS_OK file is not absolutely necessary,
+			 * the bisection process will continue at the next
+			 * bisection step.
+			 * So, just signal with a warning that something
+			 * might be wrong.
+			 */
+			warning_errno(_("could not create file '%s'"),
+				filename);
+		else
+			close(fd);
+	}
  done:
 	free(filename);
+	return res;
 }
 
 /*
@@ -938,64 +984,96 @@ void read_bisect_terms(const char **read_bad, const char **read_good)
 }
 
 /*
- * We use the convention that exiting with an exit code 10 means that
+ * We use the convention that return BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND (-10) means
  * the bisection process finished successfully.
- * In this case the calling shell script should exit 0.
+ * In this case the calling function or command should not turn a
+ * BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND return code into an error or a non zero exit code.
  *
- * If no_checkout is non-zero, the bisection process does not
- * checkout the trial commit but instead simply updates BISECT_HEAD.
+ * Checking BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND
+ * in bisect_helper::bisect_next() and only transforming it to 0 at
+ * the end of bisect_helper::cmd_bisect__helper() helps bypassing
+ * all the code related to finding a commit to test.
  */
-int bisect_next_all(struct repository *r, const char *prefix, int no_checkout)
+enum bisect_error bisect_next_all(struct repository *r, const char *prefix)
 {
 	struct rev_info revs;
 	struct commit_list *tried;
 	int reaches = 0, all = 0, nr, steps;
+	enum bisect_error res = BISECT_OK;
 	struct object_id *bisect_rev;
 	char *steps_msg;
+	/*
+	 * If no_checkout is non-zero, the bisection process does not
+	 * checkout the trial commit but instead simply updates BISECT_HEAD.
+	 */
+	int no_checkout = ref_exists("BISECT_HEAD");
+	unsigned bisect_flags = 0;
 
 	read_bisect_terms(&term_bad, &term_good);
 	if (read_bisect_refs())
 		die(_("reading bisect refs failed"));
 
-	check_good_are_ancestors_of_bad(r, prefix, no_checkout);
+	if (file_exists(git_path_bisect_first_parent()))
+		bisect_flags |= FIND_BISECTION_FIRST_PARENT_ONLY;
+
+	if (skipped_revs.nr)
+		bisect_flags |= FIND_BISECTION_ALL;
+
+	res = check_good_are_ancestors_of_bad(r, prefix, no_checkout);
+	if (res)
+		return res;
 
 	bisect_rev_setup(r, &revs, prefix, "%s", "^%s", 1);
+
+	revs.first_parent_only = !!(bisect_flags & FIND_BISECTION_FIRST_PARENT_ONLY);
 	revs.limited = 1;
 
 	bisect_common(&revs);
 
-	find_bisection(&revs.commits, &reaches, &all, !!skipped_revs.nr);
+	find_bisection(&revs.commits, &reaches, &all, bisect_flags);
 	revs.commits = managed_skipped(revs.commits, &tried);
 
 	if (!revs.commits) {
 		/*
-		 * We should exit here only if the "bad"
+		 * We should return error here only if the "bad"
 		 * commit is also a "skip" commit.
 		 */
-		exit_if_skipped_commits(tried, NULL);
-
+		res = error_if_skipped_commits(tried, NULL);
+		if (res < 0)
+			return res;
 		printf(_("%s was both %s and %s\n"),
 		       oid_to_hex(current_bad_oid),
 		       term_good,
 		       term_bad);
-		exit(1);
+
+		return BISECT_FAILED;
 	}
 
 	if (!all) {
 		fprintf(stderr, _("No testable commit found.\n"
 			"Maybe you started with bad path parameters?\n"));
-		exit(4);
+
+		return BISECT_NO_TESTABLE_COMMIT;
 	}
 
 	bisect_rev = &revs.commits->item->object.oid;
 
 	if (oideq(bisect_rev, current_bad_oid)) {
-		exit_if_skipped_commits(tried, current_bad_oid);
+		res = error_if_skipped_commits(tried, current_bad_oid);
+		if (res)
+			return res;
 		printf("%s is the first %s commit\n", oid_to_hex(bisect_rev),
 			term_bad);
+
 		show_diff_tree(r, prefix, revs.commits->item);
-		/* This means the bisection process succeeded. */
-		exit(10);
+		/*
+		 * This means the bisection process succeeded.
+		 * Using BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND (-10)
+		 * so that the call chain can simply check
+		 * for negative return values for early returns up
+		 * until the cmd_bisect__helper() caller.
+		 */
+		return BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND;
 	}
 
 	nr = all - reaches - 1;
@@ -1011,6 +1089,8 @@ int bisect_next_all(struct repository *r, const char *prefix, int no_checkout)
 		  "Bisecting: %d revisions left to test after this %s\n",
 		  nr), nr, steps_msg);
 	free(steps_msg);
+	/* Clean up objects used, as they will be reused. */
+	clear_commit_marks_all(ALL_REV_FLAGS);
 
 	return bisect_checkout(bisect_rev, no_checkout);
 }
@@ -1080,6 +1160,7 @@ int bisect_clean_state(void)
 	unlink_or_warn(git_path_bisect_names());
 	unlink_or_warn(git_path_bisect_run());
 	unlink_or_warn(git_path_bisect_terms());
+	unlink_or_warn(git_path_bisect_first_parent());
 	/* Cleanup head-name if it got left by an old version of git-bisect */
 	unlink_or_warn(git_path_head_name());
 	/*