gnu: raptor2: Fix build.

* gnu/packages/rdf.scm (raptor2)[source]: Add patch.
* gnu/packages/patches/raptor2-libxml2.patch: New file.
* gnu/local.mk (dist_patch_DATA): Register it.

Change-Id: I690a6a9120692f81f68e20e3b0fdc96f04fbfb32

gnu/local.mk

@@ -2227,6 +2227,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/rtosc-0.3.1-fix-invalid-comparison-operator.patch	\
   %D%/packages/patches/racket-chez-scheme-bin-sh.patch		\
   %D%/packages/patches/racket-launcher-config-dir.patch		\
+  %D%/packages/patches/raptor2-libxml2.patch			\
   %D%/packages/patches/racket-rktio-bin-sh.patch		\
   %D%/packages/patches/re2c-Use-maximum-alignment.patch         \
   %D%/packages/patches/reduce-unbundle-libffi.patch             \

gnu/packages/patches/raptor2-libxml2.patch

@@ -0,0 +1,30 @@
+https://bugs.gentoo.org/906227
+https://github.com/dajobe/raptor/issues/59
+https://github.com/dajobe/raptor/pull/58
+
+From 4dbc4c1da2a033c497d84a1291c46f416a9cac51 Mon Sep 17 00:00:00 2001
+From: David Anes <david.anes@suse.com>
+Date: Thu, 4 May 2023 11:54:02 +0200
+Subject: [PATCH] Remove the access to entities 'checked' private symbol for
+ libxml2 2.11.0
+
+Since version 2.11.0, some private symbols that were never intended
+as public API/ABI have been removed from libxml2, therefore the field
+'checked' is no longer present and raptor fails to build in this
+scenario.
+--- a/src/raptor_libxml.c
++++ b/src/raptor_libxml.c
+@@ -246,10 +246,11 @@ raptor_libxml_getEntity(void* user_data, const xmlChar *name)
+     
+     ret->owner = 1;
+ 
+-#if LIBXML_VERSION >= 20627
++#if LIBXML_VERSION >= 20627 && LIBXML_VERSION < 21100
+     /* Checked field was released in 2.6.27 on 2006-10-25
+      * http://git.gnome.org/browse/libxml2/commit/?id=a37a6ad91a61d168ecc4b29263def3363fff4da6
+      *
++     * and was later removed in version 2.11.0
+      */
+ 
+     /* Mark this entity as having been checked - never do this again */
+

gnu/packages/rdf.scm

@@ -77,7 +77,8 @@
                                  "-" version ".tar.gz"))
              (sha256
               (base32
-               "1026whyxpajwijlr4k5c0iliwn09mwxrg7gkvd5kb0n9ga6vg788"))))
+               "1026whyxpajwijlr4k5c0iliwn09mwxrg7gkvd5kb0n9ga6vg788"))
+             (patches (search-patches "raptor2-libxml2.patch"))))
     (build-system gnu-build-system)
     (inputs
      (list curl libxml2 libxslt zlib))