windows: restore windows 7 support on Python 3.8

Closes #101.

Author: Jason Mobarak

cpython-windows/build.py

@@ -1869,16 +1869,17 @@ def find_additional_dependencies(project: pathlib.Path):
         {"name": "shlwapi", "system": True},
         {"name": "version", "system": True},
         {"name": "ws2_32", "system": True},
-        # pathcch is Windows 8+ only. Python 3.9 dropped support for Windows 7.
-        # So this dependency is technically incorrect on Python 3.8.
-        {"name": "pathcch", "system": True},
         # In addition to the ones explicitly in the project, there are some
         # implicit link libraries not present. We list those as well.
         {"name": "Ole32", "system": True},
         {"name": "OleAut32", "system": True},
         {"name": "User32", "system": True},
     ]
 
+    # pathcch is required on 3.9+ and its presence drops support for Windows 7.
+    if python_majmin != "3.8":
+        res["core"]["links"].append({"name": "pathcch", "system": True})
+
     # Copy files for extensions into their own directories.
     for ext in sorted(extension_projects):
         dest_dir = out_dir / "build" / "extensions" / ext

docs/running.rst

@@ -75,10 +75,11 @@ Linux system.
 Windows
 -------
 
-Windows distributions require Windows 8 or Windows Server 2012 or newer. (The
-official Python distributions support Windows 7 up to Python 3.8 and dropped
-support for Windows 7 with Python 3.9. However, we've decided to drop
-support for Windows 7 from our Windows distributions.)
+Windows distributions model the requirements of the official Python
+distributions:
+
+* Windows 7 or Windows Server 2012 or newer on Python 3.8.
+* Windows 8 or Windows Server 2012 or newer on Python 3.9+.
 
 Windows binaries have a dependency on the Microsoft Visual C++ Redistributable,
 likely from MSVC 2015 (``vcruntime140.dll``). This dependency is not