1 files changed, 2 insertions, 2 deletions

diff --git a/src/lj_strfmt.c b/src/lj_strfmt.c
index 5c808290..71ee9f62 100644
--- a/src/lj_strfmt.c
+++ b/src/lj_strfmt.c
@@ -102,7 +102,7 @@ retlit:
 char * LJ_FASTCALL lj_strfmt_wint(char *p, int32_t k)
 {
   uint32_t u = (uint32_t)k;
-  if (k < 0) { u = (uint32_t)-k; *p++ = '-'; }
+  if (k < 0) { u = ~u+1u; *p++ = '-'; }
   if (u < 10000) {
     if (u < 10) goto dig1;
     if (u < 100) goto dig2;
@@ -287,7 +287,7 @@ SBuf *lj_strfmt_putfxint(SBuf *sb, SFormat sf, uint64_t k)
   /* Figure out signed prefixes. */
   if (STRFMT_TYPE(sf) == STRFMT_INT) {
     if ((int64_t)k < 0) {
-      k = (uint64_t)-(int64_t)k;
+      k = ~k+1u;
       prefix = 256 + '-';
     } else if ((sf & STRFMT_F_PLUS)) {
       prefix = 256 + '+';