gh-129393: Make 'sys.platform' return "freebsd" only on FreeBSD without major version

Author: michael-o

Doc/library/sys.rst

@@ -1422,6 +1422,7 @@ always available. Unless explicitly noted otherwise, all variables are read-only
    AIX              ``'aix'``
    Android          ``'android'``
    Emscripten       ``'emscripten'``
+   FreeBSD          ``'freebsd'``
    iOS              ``'ios'``
    Linux            ``'linux'``
    macOS            ``'darwin'``
@@ -1432,12 +1433,12 @@ always available. Unless explicitly noted otherwise, all variables are read-only
 
    On Unix systems not listed in the table, the value is the lowercased OS name
    as returned by ``uname -s``, with the first part of the version as returned by
-   ``uname -r`` appended, e.g. ``'sunos5'`` or ``'freebsd8'``, *at the time
-   when Python was built*.  Unless you want to test for a specific system
-   version, it is therefore recommended to use the following idiom::
+   ``uname -r`` appended, e.g. ``'sunos5'``, *at the time when Python was built*.
+   Unless you want to test for a specific system version, it is therefore
+   recommended to use the following idiom::
 
-      if sys.platform.startswith('freebsd'):
-          # FreeBSD-specific code here...
+      if sys.platform.startswith('sunos'):
+          # SunOS-specific code here...
 
    .. versionchanged:: 3.3
       On Linux, :data:`sys.platform` doesn't contain the major version anymore.
@@ -1451,6 +1452,10 @@ always available. Unless explicitly noted otherwise, all variables are read-only
       On Android, :data:`sys.platform` now returns ``'android'`` rather than
       ``'linux'``.
 
+   .. versionchanged:: 3.14
+      On FreeBSD, :data:`sys.platform` doesn't contain the major version anymore.
+      It is always ``'freebsd'``, instead of ``'freebsd13'`` or ``'freebsd14'``.
+
    .. seealso::
 
       :data:`os.name` has a coarser granularity.  :func:`os.uname` gives

Doc/whatsnew/3.14.rst

@@ -649,6 +649,9 @@ sys
   which only exists in specialized builds of Python, may now return objects
   from other interpreters than the one it's called in.
 
+* On FreeBSD, :data:`sys.platform` doesn't contain the major version anymore.
+  It is always ``'freebsd'``, instead of ``'freebsd13'`` or ``'freebsd14'``.
+
 sys.monitoring
 --------------
 

Misc/NEWS.d/next/Core_and_Builtins/2025-01-28-10-26-04.gh-issue-129393.0eICq6.rst

@@ -0,0 +1,2 @@
+On FreeBSD, :data:`sys.platform` doesn't contain the major version anymore.
+It is always ``'freebsd'``, instead of ``'freebsd13'`` or ``'freebsd14'``.

configure.ac

@@ -365,6 +365,7 @@ then
 
     case $MACHDEP in
 	aix*) MACHDEP="aix";;
+	freebsd*) MACHDEP="freebsd";;
 	linux-android*) MACHDEP="android";;
 	linux*) MACHDEP="linux";;
 	cygwin*) MACHDEP="cygwin";;