Honor the 'SOURCE_DATE_EPOCH' environment variable to allow for
determinitic builds.

--- a/Lib/py_compile.py
+++ b/Lib/py_compile.py
@@ -105,7 +105,10 @@ def compile(file, cfile=None, dfile=None, doraise=False):
     """
     with open(file, 'U') as f:
         try:
-            timestamp = long(os.fstat(f.fileno()).st_mtime)
+            if 'SOURCE_DATE_EPOCH' in os.environ:
+                timestamp = long(os.environ['SOURCE_DATE_EPOCH'])
+            else:
+                timestamp = long(os.fstat(f.fileno()).st_mtime)
         except AttributeError:
             timestamp = long(os.stat(file).st_mtime)
         codestring = f.read()
diff --git a/Python/import.c b/Python/import.c
index e47ce63..7eecf9c 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -945,6 +945,11 @@ write_compiled_module(PyCodeObject *co, char *cpathname, struct stat *srcstat, t
     /* Now write the true mtime (as a 32-bit field) */
     fseek(fp, 4L, 0);
     assert(mtime <= 0xFFFFFFFF);
+    if (Py_GETENV("SOURCE_DATE_EPOCH") != NULL) {
+	const char *epoch = Py_GETENV("SOURCE_DATE_EPOCH");
+	mtime = atoi(epoch);
+    }
+
     PyMarshal_WriteLongToFile((long)mtime, fp, Py_MARSHAL_VERSION);
     fflush(fp);
     fclose(fp);
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<tr><td><span title='2024-04-03 17:18:38 +0100'>2024-04-03</span></td><td><a href='/guix/commit/gnu/installer/newt?id=ac19e038b457d0585812091200005befd9b29259'>Switch order of the default substitute servers.</a><span class='msg-avail'>...<span class='msg-tooltip'>The aim here is to improve the user experience.  There's anecdotal evidence
that the network performance for bordeaux is better compared to ci at least
for some users, and I don't know of any issues with rate limiting or access
restriction for bordeaux compared to ci.  It also has IPv6 support.

Additionally, bordeaux generally had more substitutes than ci, particularly
for aarch64-linux and armhf-linux.  This change will offer a very slight
speedup for those substitutes that only bordeaux has.

Bordeaux has been a default substitute server for nearly 3 years now and I
think this change is overdue.  I'm also hopeful that we'll be able to build on
the testing regarding mirrors for bordeaux, and that'll allow potentially
improving the hosting setup (through providing more redundancy) and further
improving substitute fetching for users who currently have issues with
substitute access.

* config-daemon.ac: Switch substitute urls order.
* doc/guix.texi: Ditto.
* etc/guix-install.sh: Ditto.
* gnu/installer/newt/network.scm (wait-service-online): Ditto.
* guix/store.scm (%default-substitute-urls): Ditto.

Change-Id: I4f6d93ae1fc8b03d80b47b18b5749a51f1fde17b
Signed-off-by: Christopher Baines &lt;mail@cbaines.net&gt;
</span></span></td><td>Christopher Baines</td></tr>
<tr><td><span title='2022-11-15 12:16:43 +0100'>2022-11-15</span></td><td><a href='/guix/commit/gnu/installer/newt?id=514fedbf3966b7fbab31a6c63b4210ec8b5b0c9a'>installer: Report known-unsupported PCI devices.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/installer/hardware.scm: New file.
* gnu/local.mk (INSTALLER_MODULES): Add it.
* po/guix/POTFILES.in: Add it.
* gnu/installer.scm (installer-steps): Pass #:pci-database to the
'welcome' step procedure.
* gnu/installer/newt.scm (welcome-page): Add #:pci-database and pass it
to 'run-welcome-page'.
* gnu/installer/newt/welcome.scm (check-hardware-support): Add #:pci-database.
Enumerate unsupported PCI devices and run an error page when unsupported
devices are found.
(run-welcome-page): Add #:pci-database and pass it to
'check-hardware-support' and to the recursive call.
* gnu/installer/record.scm (&lt;installer&gt;)[welcome-page]: Adjust comment.
* doc/guix.texi (Hardware Considerations): Mention it.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-11-15 12:16:43 +0100'>2022-11-15</span></td><td><a href='/guix/commit/gnu/installer/newt?id=6b39c3afccbc2fa91746f379f46f6acfa47c8f62'>installer: Error page width is parameterized.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/installer/newt/page.scm (run-error-page): Add #:width and honor
it.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-11-15 12:16:42 +0100'>2022-11-15</span></td><td><a href='/guix/commit/gnu/installer/newt?id=4f7ffb97a4c2f2ee7aa1c54c23a97e7c0447c08c'>installer: Warn about hardware support after the welcome page.</a><span class='msg-avail'>...<span class='msg-tooltip'>This is a followup to 682639c107908426fe6bf0a1b8404b98b7820290, which
added the uvesafb upfront, before welcome page had been displayed.

* gnu/installer/newt/welcome.scm (check-hardware-support): New
procedure.
(run-welcome-page): Use it.
</span></span></td><td>Ludovic Courtès</td></tr>