in math.h make lgamma_r and non-double bessel _GNU_SOURCE only

[musl] / src / math / lgamma.c

diff --git a/src/math/lgamma.c b/src/math/lgamma.c
index d12462b..9af7eee 100644 (file)
--- a/src/math/lgamma.c
+++ b/src/math/lgamma.c
@@ -1,3 +1,4 @@
+#define _GNU_SOURCE
 #include "libm.h"
 
 double lgamma(double x)