1 files changed, 6 insertions, 1 deletions
diff --git a/sv.c b/sv.c
index a2646f758c..1933945dcd 100644
--- a/sv.c
+++ b/sv.c
@@ -9194,7 +9194,12 @@ Perl_sv_vcatpvfn(pTHX_ SV *sv, const char *pat, STRLEN patlen, va_list *args, SV
 		: SvNV(argsv);
 
 	    need = 0;
-	    if (c != 'e' && c != 'E' && nv == nv) {
+#if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
+	    if (c != 'e' && c != 'E' && !Perl_isnan(nv))
+#else
+	    if (c != 'e' && c != 'E' && nv == nv)
+#endif
+	    {
 		i = PERL_INT_MIN;
 		/* FIXME: if HAS_LONG_DOUBLE but not USE_LONG_DOUBLE this
 		   will cast our (long double) to (double) */