1 files changed, 1 insertions, 1 deletions
diff --git a/doio.c b/doio.c
index d2385f0e84..08264a93fa 100644
--- a/doio.c
+++ b/doio.c
@@ -217,7 +217,7 @@ Perl_do_open9(pTHX_ GV *gv, register char *name, I32 len, int as_raw,
 	if (*type == '|') {
 	    if (num_svs && (tlen != 2 || type[1] != '-')) {
 	      unknown_desr:
-		Perl_croak(aTHX_ "Unknown open() mode '%.*s'", olen, oname);
+		Perl_croak(aTHX_ "Unknown open() mode '%.*s'", (int)olen, oname);
 	    }
 	    /*SUPPRESS 530*/
 	    for (type++, tlen--; isSPACE(*type); type++, tlen--) ;