From: Daniel Drake <dsd@gentoo.org>

Using glibc-2.7 with the Makefile fixed to install the signalfd and eventfd
headers.

A simple program that just includes <sys/signalfd.h> fails to compile:

In file included from /usr/include/sys/signalfd.h:8,
                 from core.c:40:
/usr/include/gentoo-multilib/amd64/sys/signalfd.h:54: error: expected ')' before
numeric constant
/usr/include/gentoo-multilib/amd64/sys/signalfd.h:54: error: expected ',' or ';'
before ')' token

The problem is with the __nonnull annotation expanding to:
     __attribute__ ((__nonnull__ 2))

whereas it should be:
     __attribute__ ((__nonnull__ (2)))

Index: glibc-2.7/sysdeps/unix/sysv/linux/sys/signalfd.h
===================================================================
--- glibc-2.7.orig/sysdeps/unix/sysv/linux/sys/signalfd.h
+++ glibc-2.7/sysdeps/unix/sysv/linux/sys/signalfd.h
@@ -51,7 +51,7 @@ __BEGIN_DECLS
 /* Request notification for delivery of signals in MASK to be
    performed using descriptor FD.*/
 extern int signalfd (int __fd, const sigset_t *__mask, int __flags)
-  __nonnull (2) __THROW;
+  __nonnull ((2)) __THROW;
 
 __END_DECLS