gnu: Add libc-for-target and glibc/hurd.

* gnu/packages/patches/glibc-2.37-hurd-clock_t_centiseconds.patch
* gnu/packages/patches/glibc-2.37-hurd-local-clock_gettime_MONOTONIC.patch
* gnu/packages/patches/glibc-2.37-versioned-locpath.patch: New patches.
* gnu/local.mk (dist_patch_DATA): Register them.

* gnu/packages/base.scm (glibc/hurd, libc-for-target): New variables.
(glibc/hurd-headers): Use glibc/hurd.
* gnu/packages/commencement.scm (glibc-final-with-bootstrap-bash)[outputs,
source, arguments]
(glibc-final)[source]: Use libc-for-target instead of glibc.
* gnu/packages/cross-base.scm (cross-libc/deprecated, cross-libc*): Use
libc-for-target.

This part fixes

    https://issues.guix.gnu.org/63641#25

* gnu/packages/commencement.scm (%final-inputs): Change to memoized lambda
taking "system".
* gnu/packages/commencement.scm (canonical-package): Likewise, and update
user, passing (%current-system).
(make-gcc-toolchain): Update user, passing (%current-system).
* gnu/packages/base.scm (%final-inputs): Likewise.
* guix/scripts/refresh.scm (options->update-specs): Likewise.
* guix/build-system/gnu.scm (standard-packages): Add optional "system"
parameter.
(lower): Update caller.

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

1 files changed, 61 insertions, 0 deletions

diff --git a/gnu/packages/patches/glibc-2.37-hurd-clock_t_centiseconds.patch b/gnu/packages/patches/glibc-2.37-hurd-clock_t_centiseconds.patch
new file mode 100644
index 0000000000..944b2fe8df
--- /dev/null
+++ b/gnu/packages/patches/glibc-2.37-hurd-clock_t_centiseconds.patch
@@ -0,0 +1,61 @@
+Taken from: https://salsa.debian.org/glibc-team/glibc/-/blob/9ce19663f00176f30d6eab29fd14db3e7cd53dcf/debian/patches/hurd-i386/unsubmitted-clock_t_centiseconds.diff
+
+Some applications assume centisecond precision, or at most millisecond precision
+(e.g. guile).  This is a work-around for them.
+
+---
+ getclktck.c |    5 ++---
+ setitimer.c |    2 +-
+ times.c     |    2 +-
+ 4 files changed, 8 insertions(+), 9 deletions(-)
+commit d57f2f9b4bd007846af2fb4217486ea572579010
+Author: Richard Braun <rbraun@sceen.net>
+Date:   Tue Aug 27 11:35:31 2013 +0200
+
+    Express CPU time (clock_t of times(2)) in centiseconds
+
+diff --git a/sysdeps/mach/hurd/getclktck.c b/sysdeps/mach/hurd/getclktck.c
+index 69be2cc..5f7d946 100644
+--- a/sysdeps/mach/hurd/getclktck.c
++++ b/sysdeps/mach/hurd/getclktck.c
+@@ -18,12 +18,11 @@
+ 
+ #include <time.h>
+ 
+-/* Return frequency of `times'.
+-   Since Mach reports CPU times in microseconds, we always use 1 million.  */
++/* Return frequency of `times'.  */
+ int
+ __getclktck (void)
+ {
+-  return 1000000;
++  return 100;
+ }
+ 
+ /* Before glibc 2.2, the Hurd actually did this differently, so we
+diff --git a/sysdeps/mach/hurd/setitimer.c b/sysdeps/mach/hurd/setitimer.c
+index 39b6b16..4992c89 100644
+--- a/sysdeps/mach/hurd/setitimer.c
++++ b/sysdeps/mach/hurd/setitimer.c
+@@ -42,7 +42,7 @@ quantize_timeval (struct timeval *tv)
+   static time_t quantum = -1;
+ 
+   if (quantum == -1)
+-    quantum = 1000000 / __getclktck ();
++    quantum = 100 / __getclktck ();
+ 
+   tv->tv_usec = ((tv->tv_usec + (quantum - 1)) / quantum) * quantum;
+   if (tv->tv_usec >= 1000000)
+diff --git a/sysdeps/mach/hurd/times.c b/sysdeps/mach/hurd/times.c
+index 9e13a75..593c33a 100644
+--- a/sysdeps/mach/hurd/times.c
++++ b/sysdeps/mach/hurd/times.c
+@@ -29,7 +29,7 @@
+ static inline clock_t
+ clock_from_time_value (const time_value_t *t)
+ {
+-  return t->seconds * 1000000 + t->microseconds;
++  return t->seconds * 100 + t->microseconds / 10000;
+ }
+ 
+ /* Store the CPU time used by this process and all its