thodg/libgit2

diff --git a/src/diff.c b/src/diff.c
index 3e52e3f..4085c5f 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -77,7 +77,7 @@ void git_diff_addref(git_diff *diff)
 
 size_t git_diff_num_deltas(const git_diff *diff)
 {
-	assert(diff);
+	GIT_ASSERT_ARG(diff);
 	return diff->deltas.length;
 }
 
@@ -86,7 +86,7 @@ size_t git_diff_num_deltas_of_type(const git_diff *diff, git_delta_t type)
 	size_t i, count = 0;
 	const git_diff_delta *delta;
 
-	assert(diff);
+	GIT_ASSERT_ARG(diff);
 
 	git_vector_foreach(&diff->deltas, i, delta) {
 		count += (delta->status == type);
@@ -97,7 +97,7 @@ size_t git_diff_num_deltas_of_type(const git_diff *diff, git_delta_t type)
 
 const git_diff_delta *git_diff_get_delta(const git_diff *diff, size_t idx)
 {
-	assert(diff);
+	GIT_ASSERT_ARG_WITH_RETVAL(diff, NULL);
 	return git_vector_get(&diff->deltas, idx);
 }
 
@@ -108,7 +108,7 @@ int git_diff_is_sorted_icase(const git_diff *diff)
 
 int git_diff_get_perfdata(git_diff_perfdata *out, const git_diff *diff)
 {
-	assert(out);
+	GIT_ASSERT_ARG(out);
 	GIT_ERROR_CHECK_VERSION(out, GIT_DIFF_PERFDATA_VERSION, "git_diff_perfdata");
 	out->stat_calls = diff->perf.stat_calls;
 	out->oid_calculations = diff->perf.oid_calculations;
@@ -127,7 +127,7 @@ int git_diff_foreach(
 	git_diff_delta *delta;
 	size_t idx;
 
-	assert(diff);
+	GIT_ASSERT_ARG(diff);
 
 	git_vector_foreach(&diff->deltas, idx, delta) {
 		git_patch *patch;
@@ -243,8 +243,9 @@ int git_diff_format_email(
 	size_t allocsize;
 	int error;
 
-	assert(out && diff && opts);
-	assert(opts->summary && opts->id && opts->author);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(diff);
+	GIT_ASSERT_ARG(opts && opts->summary && opts->id && opts->author);
 
 	GIT_ERROR_CHECK_VERSION(opts,
 		GIT_DIFF_FORMAT_EMAIL_OPTIONS_VERSION,
@@ -326,7 +327,9 @@ int git_diff_commit_as_email(
 		GIT_DIFF_FORMAT_EMAIL_OPTIONS_INIT;
 	int error;
 
-	assert (out && repo && commit);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(repo);
+	GIT_ASSERT_ARG(commit);
 
 	opts.flags = flags;
 	opts.patch_no = patch_no;
diff --git a/src/diff_driver.c b/src/diff_driver.c
index 831d326..606c391 100644
--- a/src/diff_driver.c
+++ b/src/diff_driver.c
@@ -358,7 +358,7 @@ int git_diff_driver_lookup(
 	int error = 0;
 	const char *values[1], *attrs[] = { "diff" };
 
-	assert(out);
+	GIT_ASSERT_ARG(out);
 	*out = NULL;
 
 	if (!repo || !path || !strlen(path))
diff --git a/src/diff_generate.c b/src/diff_generate.c
index e7bfd62..f021a26 100644
--- a/src/diff_generate.c
+++ b/src/diff_generate.c
@@ -128,7 +128,7 @@ static int diff_delta__from_one(
 	git_diff_delta *delta;
 	const char *matched_pathspec;
 
-	assert((oitem != NULL) ^ (nitem != NULL));
+	GIT_ASSERT_ARG((oitem != NULL) ^ (nitem != NULL));
 
 	if (oitem) {
 		entry = oitem;
@@ -160,7 +160,7 @@ static int diff_delta__from_one(
 	GIT_ERROR_CHECK_ALLOC(delta);
 
 	/* This fn is just for single-sided diffs */
-	assert(status != GIT_DELTA_MODIFIED);
+	GIT_ASSERT(status != GIT_DELTA_MODIFIED);
 	delta->nfiles = 1;
 
 	if (has_old) {
@@ -408,7 +408,9 @@ static git_diff_generated *diff_generated_alloc(
 	git_diff_generated *diff;
 	git_diff_options dflt = GIT_DIFF_OPTIONS_INIT;
 
-	assert(repo && old_iter && new_iter);
+	GIT_ASSERT_ARG_WITH_RETVAL(repo, NULL);
+	GIT_ASSERT_ARG_WITH_RETVAL(old_iter, NULL);
+	GIT_ASSERT_ARG_WITH_RETVAL(new_iter, NULL);
 
 	if ((diff = git__calloc(1, sizeof(git_diff_generated))) == NULL)
 		return NULL;
@@ -589,7 +591,7 @@ int git_diff__oid_for_entry(
 	git_filter_list *fl = NULL;
 	int error = 0;
 
-	assert(d->type == GIT_DIFF_TYPE_GENERATED);
+	GIT_ASSERT(d->type == GIT_DIFF_TYPE_GENERATED);
 	diff = (git_diff_generated *)d;
 
 	memset(out, 0, sizeof(*out));
@@ -1302,7 +1304,8 @@ int git_diff_tree_to_tree(
 	char *prefix = NULL;
 	int error = 0;
 
-	assert(out && repo);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(repo);
 
 	*out = NULL;
 
@@ -1358,7 +1361,8 @@ int git_diff_tree_to_index(
 	bool index_ignore_case = false;
 	int error = 0;
 
-	assert(out && repo);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(repo);
 
 	*out = NULL;
 
@@ -1401,7 +1405,8 @@ int git_diff_index_to_workdir(
 	char *prefix = NULL;
 	int error = 0;
 
-	assert(out && repo);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(repo);
 
 	*out = NULL;
 
@@ -1444,7 +1449,8 @@ int git_diff_tree_to_workdir(
 	git_index *index;
 	int error;
 
-	assert(out && repo);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(repo);
 
 	*out = NULL;
 
@@ -1477,7 +1483,8 @@ int git_diff_tree_to_workdir_with_index(
 	git_index *index = NULL;
 	int error = 0;
 
-	assert(out && repo);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(repo);
 
 	*out = NULL;
 
@@ -1513,7 +1520,9 @@ int git_diff_index_to_index(
 	char *prefix = NULL;
 	int error;
 
-	assert(out && old_index && new_index);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(old_index);
+	GIT_ASSERT_ARG(new_index);
 
 	*out = NULL;
 
diff --git a/src/diff_print.c b/src/diff_print.c
index 0e93fe8..062e267 100644
--- a/src/diff_print.c
+++ b/src/diff_print.c
@@ -95,7 +95,7 @@ static int diff_print_info_init_frompatch(
 	git_diff_line_cb cb,
 	void *payload)
 {
-	assert(patch);
+	GIT_ASSERT_ARG(patch);
 
 	memset(pi, 0, sizeof(diff_print_info));
 
@@ -766,7 +766,9 @@ int git_diff_to_buf(git_buf *out, git_diff *diff, git_diff_format_t format)
 {
 	int error;
 
-	assert(out && diff);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(diff);
+
 	if ((error = git_buf_sanitize(out)) < 0)
 		return error;
 
@@ -783,7 +785,8 @@ int git_patch_print(
 	diff_print_info pi;
 	int error;
 
-	assert(patch && print_cb);
+	GIT_ASSERT_ARG(patch);
+	GIT_ASSERT_ARG(print_cb);
 
 	if ((error = diff_print_info_init_frompatch(&pi, &temp, patch,
 						    GIT_DIFF_FORMAT_PATCH, print_cb, payload)) < 0)
@@ -805,7 +808,8 @@ int git_patch_to_buf(git_buf *out, git_patch *patch)
 {
 	int error;
 
-	assert(out && patch);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(patch);
 
 	if ((error = git_buf_sanitize(out)) < 0)
 		return error;
diff --git a/src/diff_stats.c b/src/diff_stats.c
index f5fda79..41a25bf 100644
--- a/src/diff_stats.c
+++ b/src/diff_stats.c
@@ -183,7 +183,8 @@ int git_diff_get_stats(
 	git_diff_stats *stats = NULL;
 	int error = 0;
 
-	assert(out && diff);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(diff);
 
 	stats = git__calloc(1, sizeof(git_diff_stats));
 	GIT_ERROR_CHECK_ALLOC(stats);
@@ -251,7 +252,7 @@ int git_diff_get_stats(
 size_t git_diff_stats_files_changed(
 	const git_diff_stats *stats)
 {
-	assert(stats);
+	GIT_ASSERT_ARG(stats);
 
 	return stats->files_changed;
 }
@@ -259,7 +260,7 @@ size_t git_diff_stats_files_changed(
 size_t git_diff_stats_insertions(
 	const git_diff_stats *stats)
 {
-	assert(stats);
+	GIT_ASSERT_ARG(stats);
 
 	return stats->insertions;
 }
@@ -267,7 +268,7 @@ size_t git_diff_stats_insertions(
 size_t git_diff_stats_deletions(
 	const git_diff_stats *stats)
 {
-	assert(stats);
+	GIT_ASSERT_ARG(stats);
 
 	return stats->deletions;
 }
@@ -282,7 +283,8 @@ int git_diff_stats_to_buf(
 	size_t i;
 	const git_diff_delta *delta;
 
-	assert(out && stats);
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(stats);
 
 	if (format & GIT_DIFF_STATS_NUMBER) {
 		for (i = 0; i < stats->files_changed; ++i) {
diff --git a/src/diff_tform.c b/src/diff_tform.c
index 7de88bd..03fc2b0 100644
--- a/src/diff_tform.c
+++ b/src/diff_tform.c
@@ -87,7 +87,7 @@ git_diff_delta *git_diff__merge_like_cgit(
 		a->status == GIT_DELTA_UNREADABLE)
 		return dup;
 
-	assert(b->status != GIT_DELTA_UNMODIFIED);
+	GIT_ASSERT_WITH_RETVAL(b->status != GIT_DELTA_UNMODIFIED, NULL);
 
 	/* A cgit exception is that the diff of a file that is only in the
 	 * index (i.e. not in HEAD nor workdir) is given as empty.
@@ -121,7 +121,8 @@ int git_diff__merge(
 	bool ignore_case, reversed;
 	unsigned int i, j;
 
-	assert(onto && from);
+	GIT_ASSERT_ARG(onto);
+	GIT_ASSERT_ARG(from);
 
 	if (!from->deltas.length)
 		return 0;
@@ -815,7 +816,7 @@ int git_diff_find_similar(
 	diff_find_match *best_match;
 	git_diff_file swap;
 
-	assert(diff);
+	GIT_ASSERT_ARG(diff);
 
 	if ((error = normalize_find_opts(diff, &opts, given_opts)) < 0)
 		return error;
@@ -978,7 +979,7 @@ find_best_matches:
 				src->flags |= GIT_DIFF_FLAG__TO_DELETE;
 				num_rewrites++;
 			} else {
-				assert(delta_is_split(tgt));
+				GIT_ASSERT(delta_is_split(tgt));
 
 				if (best_match->similarity < opts.rename_from_rewrite_threshold)
 					continue;
@@ -988,7 +989,7 @@ find_best_matches:
 				delta_make_rename(tgt, src, best_match->similarity);
 				num_rewrites--;
 
-				assert(src->status == GIT_DELTA_DELETED);
+				GIT_ASSERT(src->status == GIT_DELTA_DELETED);
 				memcpy(&src->old_file, &swap, sizeof(src->old_file));
 				memset(&src->new_file, 0, sizeof(src->new_file));
 				src->new_file.path = src->old_file.path;
@@ -1024,7 +1025,7 @@ find_best_matches:
 
 				num_updates++;
 			} else {
-				assert(delta_is_split(src));
+				GIT_ASSERT(delta_is_split(src));
 
 				if (best_match->similarity < opts.rename_from_rewrite_threshold)
 					continue;