--- /dev/null
+--- a/libc/sysdeps/linux/common/bits/mathcalls.h
++++ b/libc/sysdeps/linux/common/bits/mathcalls.h
+@@ -229,7 +229,7 @@
+
+
+ /* Return nonzero if VALUE is not a number. */
+-__MATHDECL_PRIV (int,__isnan,, (_Mdouble_ __value), (__const__));
++__MATHDECL_PRIV (int,isnan,, (_Mdouble_ __value), (__const__));
+
+ #if defined __USE_MISC || defined __USE_XOPEN
+ /* Return nonzero if VALUE is not a number. */