gnu: xen: Build reproducibly

* gnu/packages/virtualization.scm (xen)[source]: Add patches.
[arguments]: Add a new 'remove-cruft phase.
* gnu/packages/patches/xen-docs-use-predictable-ordering.patch,
* gnu/packages/patches/xen-remove-config.gz-timestamp.patch: New files.
* gnu/local.mk (dist_patch_DATA): Add them both.

gnu/local.mk

@@ -2121,6 +2121,8 @@ dist_patch_DATA =						\
   %D%/packages/patches/wpa-supplicant-dbus-group-policy.patch		\
   %D%/packages/patches/x265-arm-flags.patch			\
   %D%/packages/patches/xdg-desktop-portal-wlr-harcoded-length.patch\
+  %D%/packages/patches/xen-docs-use-predictable-ordering.patch	\
+  %D%/packages/patches/xen-remove-config.gz-timestamp.patch	\
   %D%/packages/patches/xf86-video-ark-remove-mibstore.patch	\
   %D%/packages/patches/xf86-video-nouveau-fixup-ABI.patch	\
   %D%/packages/patches/xf86-video-savage-xorg-compat.patch 	\

gnu/packages/patches/xen-docs-use-predictable-ordering.patch

@@ -0,0 +1,34 @@
+From: Tobias Geerinckx-Rice <me@tobias.gr>
+Date: Sun Sep 24 02:00:00 2023 +0200
+Subject: xen: docs: Use predictable ordering.
+
+What follows was taken verbatim from Debian.  See:
+https://sources.debian.org/patches/xen/4.14.5%2B94-ge49571868d-1/
+
+From: Maximilian Engelhardt <maxi@daemonizer.de>
+Date: Fri, 18 Dec 2020 21:42:34 +0100
+Subject: docs: use predictable ordering in generated documentation
+
+When the seq number is equal, sort by the title to get predictable
+output ordering. This is useful for reproducible builds.
+
+Signed-off-by: Maximilian Engelhardt <maxi@daemonizer.de>
+Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
+(cherry picked from commit e18dadc5b709290b8038a1cacb52bc3b3b69cf21)
+---
+ docs/xen-headers | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/docs/xen-headers b/docs/xen-headers
+index 5415563..8c434d7 100755
+--- a/docs/xen-headers
++++ b/docs/xen-headers
+@@ -331,7 +331,7 @@ sub output_index () {
+ <h2>Starting points</h2>
+ <ul>
+ END
+-    foreach my $ic (sort { $a->{Seq} <=> $b->{Seq} } @incontents) {
++    foreach my $ic (sort { $a->{Seq} <=> $b->{Seq} or $a->{Title} cmp $b->{Title} } @incontents) {
+         $o .= "<li><a href=\"$ic->{Href}\">$ic->{Title}</a></li>\n";
+     }
+     $o .= "</ul>\n";

gnu/packages/patches/xen-remove-config.gz-timestamp.patch

@@ -0,0 +1,37 @@
+From: Tobias Geerinckx-Rice <me@tobias.gr>
+Date: Sun Sep 24 02:00:00 2023 +0200
+Subject: xen: docs: Use predictable ordering.
+
+What follows was taken verbatim from Debian.  See:
+https://sources.debian.org/patches/xen/4.14.5%2B94-ge49571868d-1/
+
+From: =?utf-8?b?IkZyw6lkw6lyaWMgUGllcnJldCAoZmVwaXRyZSki?=
+ <frederic.pierret@qubes-os.org>
+Date: Wed, 4 Nov 2020 09:24:40 +0100
+Subject: xen: don't have timestamp inserted in config.gz
+MIME-Version: 1.0
+Content-Type: text/plain; charset="utf-8"
+Content-Transfer-Encoding: 8bit
+
+This is for improving reproducible builds.
+
+Signed-off-by: Frédéric Pierret (fepitre) <frederic.pierret@qubes-os.org>
+Acked-by: Jan Beulich <jbeulich@suse.com>
+(cherry picked from commit 5816d327e44ab37ae08730f4c54a80835998f31f)
+---
+ xen/common/Makefile | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/xen/common/Makefile b/xen/common/Makefile
+index 06881d0..32cd650 100644
+--- a/xen/common/Makefile
++++ b/xen/common/Makefile
+@@ -77,7 +77,7 @@ obj-$(CONFIG_HAS_DEVICE_TREE) += libfdt/
+ 
+ CONF_FILE := $(if $(patsubst /%,,$(KCONFIG_CONFIG)),$(XEN_ROOT)/xen/)$(KCONFIG_CONFIG)
+ config.gz: $(CONF_FILE)
+-	gzip -c $< >$@
++	gzip -n -c $< >$@
+ 
+ config_data.o: config.gz
+ 

gnu/packages/virtualization.scm

@@ -2288,7 +2288,10 @@ (define-public xen
               (file-name (git-file-name name version))
               (sha256
                (base32
-                "1cdzpxbihkdn4za8ly0lgkbxrafjzbxjflhfn83kyg4bam1vv7mn"))))
+                "1cdzpxbihkdn4za8ly0lgkbxrafjzbxjflhfn83kyg4bam1vv7mn"))
+              (patches
+               (search-patches "xen-docs-use-predictable-ordering.patch"
+                               "xen-remove-config.gz-timestamp.patch"))))
     (build-system gnu-build-system)
     (arguments
      (list
@@ -2409,7 +2412,13 @@ (define (filter-environment! filter-predicate
               (apply invoke "make" "world"
                      "-j" (number->string
                            (if parallel-build? (parallel-job-count) 1))
-                     make-flags))))))
+                     make-flags)))
+          (add-after 'install 'remove-cruft
+            (lambda _
+              (with-directory-excursion #$output
+                ;; Delete useless (and irreproducible) build-time left-overs.
+                (for-each delete-file
+                          (find-files "share/doc" "^\\.deps$"))))))))
     (inputs
      (list acpica                       ; TODO: patch iasl invocation
            bridge-utils                 ; TODO: patch invocations