When ares is enabled, we now check for the ares_cancel function to verify
that we use a library that is recent enough to build with the latest libcurl.
diff --git a/configure.ac b/configure.ac
index 29e44f3..b265c75 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1268,6 +1268,28 @@
CPPFLAGS="$CPPFLAGS -I$enableval/include"
LDFLAGS="$LDFLAGS -L$enableval/lib"
fi
+
+ dnl verify that a sufficient c-ares is here
+ AC_MSG_CHECKING([that c-ares is good and recent enough])
+ AC_LINK_IFELSE( [
+#include <ares.h>
+/* provide a set of dummy functions in case c-ares was built with debug */
+void curl_dofree() { }
+void curl_sclose() { }
+void curl_domalloc() { }
+
+int main(void)
+{
+ ares_channel channel;
+ ares_cancel(channel);
+ return 0;
+}
+],
+ AC_MSG_RESULT(yes),
+ AC_MSG_RESULT(no)
+ AC_MSG_ERROR([c-ares library defective or too old])
+ )
+
;;
esac ],
AC_MSG_RESULT(no)
