commit 1cacdef0d1a3f587691735d1822d584b68eba593
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Tue Aug 31 17:08:00 2021

    libstdc++: Fix broken autoconf check for O_NONBLOCK
    
    Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
    
    libstdc++-v3/ChangeLog:
    
            * configure.ac: Fix checks for F_GETFL, F_SETFL and O_NONBLOCK.
            * configure: Regenerate.

diff --git a/libstdc++-v3/configure.ac b/libstdc++-v3/configure.ac
index d29efa6cb5f..2d68b3672b9 100644
--- a/libstdc++-v3/configure.ac
+++ b/libstdc++-v3/configure.ac
@@ -481,10 +481,10 @@ GLIBCXX_CHECK_FILESYSTEM_DEPS
 
 # For Networking TS.
 AC_CHECK_HEADERS([fcntl.h sys/ioctl.h sys/socket.h sys/uio.h poll.h netdb.h arpa/inet.h netinet/in.h netinet/tcp.h])
-AC_CHECK_DECL(F_GETFL,[],[],[fcntl.h])
-AC_CHECK_DECL(F_SETFL,[],[],[fcntl.h])
-if [ "$ac_cv_have_decl_F_GETFL$ac_cv_have_decl_F_SETFL" = 11 ]; then
-  AC_CHECK_DECL(O_NONBLOCK,[],[],[fcntl.h])
+AC_CHECK_DECL(F_GETFL,,,[#include <fcntl.h>])
+AC_CHECK_DECL(F_SETFL,,,[#include <fcntl.h>])
+if test "$ac_cv_have_decl_F_GETFL$ac_cv_have_decl_F_SETFL" = yesyes ; then
+  AC_CHECK_DECL(O_NONBLOCK,,,[#include <fcntl.h>])
 fi
 
 # For Transactional Memory TS