commit 327c4cdf7578debcc140f04f03d02479771c9e11
author Doug VanLeuven <roamdad@sonic.net> Fri Dec 14 14:58:30 2012 +0200
committer David Lamparter <equinox@opensourcerouting.org> Fri Jan 11 21:50:06 2013 +0100
tree a0e02a0614f12601d8a58eeeebf9e54b27198c9f
parent b2e5bdbe10c4145f508fcf1486ffe29d5ce516f7

testzebra: pragma weak: detect systems with weak alias and provide alternative

LLVM clang does not support #pragma weak (bug 3679) on OS X. There are
other systems where the #pragma weak has varying syntax.

Added m4 file from the autoconf archives:
http://www.gnu.org/software/autoconf-archive/ax_sys_weak_alias.html

Fix up zebra/*_null.c files to use #pragma weak alias or stub functions
if not available. It's incomplete in that the different format #pragma
enable easier fixes on need.

Tested on 64bit OS X 10.7, FreeBSD 9.0 amd64 & i386 (32bit) using
gcc & clang. Tested on linux 64bit.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

zebra/kernel_null.c

diff --git a/zebra/kernel_null.c b/zebra/kernel_null.c
index 6b96c6d..ec994a6 100644
--- a/zebra/kernel_null.c
+++ b/zebra/kernel_null.c
@@ -9,9 +9,19 @@
 #include "zebra/connected.h"
 
 int kernel_add_ipv4 (struct prefix *a, struct rib *b) { return 0; }
+#ifdef HAVE_SYS_WEAK_ALIAS_PRAGMA
 #pragma weak kernel_delete_ipv4 = kernel_add_ipv4
+#else
+int kernel_delete_ipv4 (struct prefix *a, struct rib *b) { return 0; }
+#endif
+
 int kernel_add_ipv6 (struct prefix *a, struct rib *b) { return 0; }
+#ifdef HAVE_SYS_WEAK_ALIAS_PRAGMA_PRAGMA
 #pragma weak kernel_delete_ipv6 = kernel_add_ipv6
+#else
+int kernel_delete_ipv6 (struct prefix *a, struct rib *b) { return 0; }
+#endif
+
 int kernel_delete_ipv6_old (struct prefix_ipv6 *dest, struct in6_addr *gate,
                             unsigned int index, int flags, int table)
 { return 0; }
@@ -38,4 +48,8 @@
 }
 
 void kernel_init (void) { return; }
+#ifdef HAVE_SYS_WEAK_ALIAS_PRAGMA
 #pragma weak route_read = kernel_init
+#else
+void route_read (void) { return; }
+#endif