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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<div class='path'>path: <a href='/guix/log/?id=6492c6496bb17effb8bd807ebfd18bf435c7d49c&amp;showmsg=1'>root</a>/<a href='/guix/log/gnu?id=6492c6496bb17effb8bd807ebfd18bf435c7d49c&amp;showmsg=1'>gnu</a>/<a href='/guix/log/gnu/packages?id=6492c6496bb17effb8bd807ebfd18bf435c7d49c&amp;showmsg=1'>packages</a>/<a href='/guix/log/gnu/packages/aux-files?id=6492c6496bb17effb8bd807ebfd18bf435c7d49c&amp;showmsg=1'>aux-files</a>/<a href='/guix/log/gnu/packages/aux-files/linux-libre?id=6492c6496bb17effb8bd807ebfd18bf435c7d49c&amp;showmsg=1'>linux-libre</a>/<a href='/guix/log/gnu/packages/aux-files/linux-libre/6.4-x86_64.conf?id=6492c6496bb17effb8bd807ebfd18bf435c7d49c&amp;showmsg=1'>6.4-x86_64.conf</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/aux-files/linux-libre/6.4-x86_64.conf?id=6492c6496bb17effb8bd807ebfd18bf435c7d49c'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2023-07-15 14:02:40 -0400'>2023-07-15</span></td><td class='logsubject'><a href='/guix/commit/gnu/packages/aux-files/linux-libre/6.4-x86_64.conf?id=49f74b67a44882d2af0529abf3e60a9c37512f2c'>gnu: Add linux-libre 6.4</a></td><td>Leo Famulari</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* gnu/packages/linux.scm (linux-libre-6.4-version, linux-libre-6.4-gnu-revision,
deblob-scripts-6.4, linux-libre-6.4-pristine-source, linux-libre-6.4-source,
linux-libre-headers-6.4, linux-libre-6.4: New variables.
* gnu/packages/aux-files/linux-libre/6.4-arm.conf,
* gnu/packages/aux-files/linux-libre/6.4-arm64.conf,
* gnu/packages/aux-files/linux-libre/6.4-i686.conf,
* gnu/packages/aux-files/linux-libre/6.4-x86_64.conf: New files.
* Makefile.am (AUX_FILES): Add them.


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