Hello,
I have a problem using c-ares in a multilib environment, for which I
found a patch in Fedora that does not seem to have found its way
upstream. The following minimal code demonstrates the problem:
% cat this.c
#include <ares.h>
int main() { return 0; }
% x86_64-pc-linux-gnu-gcc -o this -m32 this.c
In file included from /usr/include/ares.h:23:0,
from this.c:2:
/usr/include/ares_rules.h:100:3: error: size of array ‘__cares_rule_01__’
is negative
__cares_rule_01__
^
I.e. using an x86_64 compiler in 32bit mode.
The problem is in ares_build.h and solved by applying this patch (taken
from [1]):
diff -up c-ares-1.10.0/ares_build.h.in.multilib
c-ares-1.10.0/ares_build.h.in
--- c-ares-1.10.0/ares_build.h.in.multilib 2013-05-13
11:40:22.697814087 +0200
+++ c-ares-1.10.0/ares_build.h.in 2013-05-13 11:40:26.236813966 +0200
@@ -96,7 +96,14 @@
#endif
/* The size of `long', as computed by sizeof. */
-#undef CARES_SIZEOF_LONG
+#include <bits/wordsize.h>
+#if __WORDSIZE == 32
+#define CARES_SIZEOF_LONG 4
+#elif __WORDSIZE == 64
+#define CARES_SIZEOF_LONG 8
+#else
+#error "Unknown word size"
+#endif
/* Integral data type used for ares_socklen_t. */
#undef CARES_TYPEOF_ARES_SOCKLEN_T
diff -up c-ares-1.10.0/configure.ac.multilib c-ares-1.10.0/configure.ac
--- c-ares-1.10.0/configure.ac.multilib 2013-05-13 11:41:00.480812797 +0200
+++ c-ares-1.10.0/configure.ac 2013-05-13 11:41:17.210812226 +0200
@@ -457,7 +457,6 @@ AC_CHECK_SIZEOF(size_t)
AC_CHECK_SIZEOF(long)
AC_CHECK_SIZEOF(int)
AC_CHECK_SIZEOF(short)
-CARES_CONFIGURE_LONG
AC_CHECK_SIZEOF(time_t)
AC_CHECK_TYPE(long long,
I don't know if this is the correct/prefered solution for the problem,
but it solves the problem for me.
Please consider applying this or a similar patch.
Thank you.
-Markus
[1]
http://pkgs.fedoraproject.org/cgit/c-ares.git/tree/c-ares-1.10.0-multilib.patch
