diff --git a/align.c b/align.c
index 1ba2ba3..4825c03 100644
--- a/align.c
+++ b/align.c
@@ -772,7 +772,7 @@ static void mm_align1(void *km, const mm_mapopt_t *opt, const mm_idx_t *mi, int
 				re1 = rs + (ez->max_t + 1);
 				qe1 = qs + (ez->max_q + 1);
 				if (cnt1 - (j + 1) >= opt->min_cnt) {
-					mm_split_reg(r, r2, as1 + j + 1 - r->as, qlen, a, opt->flag&MM_F_QSTRAND);
+					mm_split_reg(r, r2, as1 + j + 1 - r->as, qlen, a, !!(opt->flag&MM_F_QSTRAND));
 					if (zdrop_code == 2) r2->split_inv = 1;
 				}
 				break;
diff --git a/format.c b/format.c
index b7a7be9..d2a538b 100644
--- a/format.c
+++ b/format.c
@@ -338,7 +338,7 @@ void mm_write_paf3(kstring_t *s, const mm_idx_t *mi, const mm_bseq1_t *t, const
 			mm_sprintf_lite(s, "%d%c", r->p->cigar[k]>>4, MM_CIGAR_STR[r->p->cigar[k]&0xf]);
 	}
 	if (r->p && (opt_flag & (MM_F_OUT_CS|MM_F_OUT_MD)))
-		write_cs_or_MD(km, s, mi, t, r, !(opt_flag&MM_F_OUT_CS_LONG), opt_flag&MM_F_OUT_MD, 1, opt_flag&MM_F_QSTRAND);
+		write_cs_or_MD(km, s, mi, t, r, !(opt_flag&MM_F_OUT_CS_LONG), opt_flag&MM_F_OUT_MD, 1, !!(opt_flag&MM_F_QSTRAND));
 	if ((opt_flag & MM_F_COPY_COMMENT) && t->comment)
 		mm_sprintf_lite(s, "\t%s", t->comment);
 }
diff --git a/main.c b/main.c
index 1f7b66f..063c945 100644
--- a/main.c
+++ b/main.c
@@ -7,7 +7,7 @@
 #include "mmpriv.h"
 #include "ketopt.h"
 
-#define MM_VERSION "2.21-r1071-qs-dirty"
+#define MM_VERSION "2.21-r1074-qs-dirty"
 
 #ifdef __linux__
 #include <sys/resource.h>
diff --git a/map.c b/map.c
index 2428627..c34475a 100644
--- a/map.c
+++ b/map.c
@@ -318,7 +318,7 @@ void mm_map_frag(const mm_idx_t *mi, int n_segs, const int *qlens, const char **
 	b->frag_gap = max_chain_gap_ref;
 	b->rep_len = rep_len;
 
-	regs0 = mm_gen_regs(b->km, hash, qlen_sum, n_regs0, u, a, opt->flag&MM_F_QSTRAND);
+	regs0 = mm_gen_regs(b->km, hash, qlen_sum, n_regs0, u, a, !!(opt->flag&MM_F_QSTRAND));
 	if (mi->n_alt) {
 		mm_mark_alt(mi, n_regs0, regs0);
 		mm_hit_sort(b->km, &n_regs0, regs0, opt->alt_drop); // this step can be merged into mm_gen_regs(); will do if this shows up in profile