gnu: mig: Update to 1.8+git20220827.

* gnu/packages/hurd.scm (mig): Do it.
* gnu/packages/patches/mig-cpu.h-generation.patch: New file.
* gnu/local.mk (dist_patch_DATA): Register it.

Co-authored-by: Ludovic Courtès <ludo@gnu.org>

gnu/local.mk

@@ -1542,6 +1542,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/mia-vtk9.patch				\
   %D%/packages/patches/mia-vtk92.patch				\
   %D%/packages/patches/mia-vtk-version.patch			\
+  %D%/packages/patches/mig-cpu.h-generation.patch 		\
   %D%/packages/patches/mingw-w64-6.0.0-gcc.patch		\
   %D%/packages/patches/mingw-w64-dlltool-temp-prefix.patch	\
   %D%/packages/patches/mingw-w64-reproducible-gendef.patch	\

gnu/packages/hurd.scm

@@ -111,15 +111,20 @@ GNU/Hurd."
 (define-public mig
   (package
     (name "mig")
-    (version "1.8")
-    (source
-     (origin
+    (version "1.8+git20220827")
+    (source (origin
               (method url-fetch)
-      (uri (string-append "mirror://gnu/mig/mig-"
+              ;; XXX: Version 2.35 of glibc can only be built with an
+              ;; unreleased version of MiG:
+              ;; <https://lists.gnu.org/archive/html/bug-hurd/2023-03/msg00025.html>.
+              ;; It cannot be fetched from Git though, as the extra dependency
+              ;; on Autoconf/Automake would complicate bootstrapping.
+              (uri (string-append "mirror://gnu/guix/mirror/mig-"
                                   version ".tar.gz"))
               (sha256
                (base32
-        "1gyda8sq6b379nx01hkpbd85lz39irdvz2b9wbr63gicicx8i706"))))
+                "163d37s9lscd6zxyfng421m9nl857464mgjj90xsrcl5ykbng5p2"))
+              (patches (search-patches "mig-cpu.h-generation.patch"))))
     (build-system gnu-build-system)
     ;; Flex is needed both at build and run time.
     (inputs (list gnumach-headers flex))

gnu/packages/patches/mig-cpu.h-generation.patch

@@ -0,0 +1,16 @@
+Backport MiG commit 73fbf2504ae606dda81372701a67dad6fee0865e:
+
+  From: Flavio Cruz <flaviocruz@gmail.com>
+  Subject: Generate cpu.h with -ffreestanding
+
+--- a/Makefile.in	2023-03-26 23:02:51.384318331 +0200
++++ b/Makefile.in	2023-03-26 23:03:03.300329369 +0200
+@@ -1051,7 +1051,7 @@ uninstall-am: uninstall-binSCRIPTS unins
+ .sym.symc:
+ 	$(AWK_V) $(AWK) -f $(srcdir)/gensym.awk $< > $@
+ .symc.symo:
+-	$(AM_V_CC) $(TARGET_CC) -S $(TARGET_CPPFLAGS) $(TARGET_CFLAGS) -x c -o $@ $<
++	$(AM_V_CC) $(TARGET_CC) -S $(TARGET_CPPFLAGS) $(TARGET_CFLAGS) -ffreestanding -x c -o $@ $<
+ .symo.h:
+ 	$(AM_V_GEN) sed -e '/^[^*].*$$/d' -e 's/^[*]/#define/' -e 's/mAgIc[^-0-9]*//' \
+ 	    $< > $@