libc/sysdeps: dup3: check for __NR_dup3 since older kernels/arches lack it

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

diff --git a/libc/sysdeps/linux/common/dup3.c b/libc/sysdeps/linux/common/dup3.c
index 539c071..8a57785 100644 (file)
--- a/libc/sysdeps/linux/common/dup3.c
+++ b/libc/sysdeps/linux/common/dup3.c
@@ -10,4 +10,6 @@
 #include <sys/syscall.h>
 #include <unistd.h>
 
+#if defined(__NR_dup3)
 _syscall3(int, dup3, int, oldfd, int, newfd, int, flags)
+#endif