diff --git a/include/libbb.h b/include/libbb.h
index 780bd4566..ddbde1833 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -450,6 +450,7 @@ const char *make_human_readable_str(unsigned long long size,
 /* Put a string of hex bytes ("1b2e66fe"...), return advanced pointer */
 char *bin2hex(char *buf, const char *cp, int count);
 
+/* Last element is marked by mult == 0 */
 struct suffix_mult {
 	char suffix[4];
 	unsigned mult;
diff --git a/libbb/xatonum_template.c b/libbb/xatonum_template.c
index bc8116056..205da53c8 100644
--- a/libbb/xatonum_template.c
+++ b/libbb/xatonum_template.c
@@ -45,7 +45,7 @@ unsigned type xstrtou(_range_sfx)(const char *numstr, int base,
 	 * Note that we also allow nul suffixes with associated multipliers,
 	 * to allow for scaling of the numstr by some default multiplier. */
 	if (suffixes) {
-		while (suffixes->suffix) {
+		while (suffixes->mult) {
 			if (strcmp(suffixes->suffix, e) == 0) {
 				if (XSTR_UTYPE_MAX / suffixes->mult < r)
 					goto range; /* overflow! */