1 files changed, 3 insertions, 0 deletions

diff --git a/bignum.c b/bignum.c
index 255b5d141f..5089bff950 100644
--- a/bignum.c
+++ b/bignum.c
@@ -14,6 +14,9 @@
 
 #include <math.h>
 #include <ctype.h>
+#ifdef HAVE_IEEEFP_H
+#include <ieeefp.h>
+#endif
 
 VALUE rb_cBignum;