diff --git a/src/passwd/getgrent_a.c b/src/passwd/getgrent_a.c
index ccb51d5..6958006 100644
--- a/src/passwd/getgrent_a.c
+++ b/src/passwd/getgrent_a.c
@@ -31,7 +31,7 @@ struct group *__getgrent_a(FILE *f, struct group *gr, char **line, size_t *size,
 	for (*nmem=!!*s; *s; s++)
 		if (*s==',') ++*nmem;
 	free(*mem);
-	*mem = calloc(sizeof(char *), *nmem+1);
+	*mem = calloc(sizeof **mem, *nmem+1);
 	if (!*mem) {
 		free(*line);
 		*line = 0;
@@ -40,7 +40,7 @@ struct group *__getgrent_a(FILE *f, struct group *gr, char **line, size_t *size,
 	mem[0][0] = mems;
 	for (s=mems, i=0; *s; s++)
 		if (*s==',') *s++ = 0, mem[0][++i] = s;
-	mem[0][++i] = 0;
+	mem[0][i] = 0;
 	gr->gr_mem = *mem;
 	return gr;
 }