1 files changed, 1 insertions, 1 deletions
diff --git a/complex.c b/complex.c
index fd0088c574..3186e62fc8 100644
--- a/complex.c
+++ b/complex.c
@@ -1173,7 +1173,7 @@ nucomp_eql_p(VALUE self, VALUE other)
 inline static VALUE
 f_signbit(VALUE x)
 {
-#if defined(HAVE_SIGNBIT) && defined(__GNUC__) && defined(__sun__) && \
+#if defined(HAVE_SIGNBIT) && defined(__GNUC__) && defined(__sun) && \
     !defined(signbit)
     extern int signbit(double);
 #endif