From d3240555d945e19692f62e48c7b9ca2313f35f22 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Mon, 14 Mar 2022 12:19:37 -0400
Subject: [PATCH] Backport PR #22429: Enable windows/arm64 platform

---
 doc/users/next_whats_new/windows_arm64.rst |  8 ++++
 setupext.py                                | 45 ++++++++++++++++++----
 2 files changed, 46 insertions(+), 7 deletions(-)
 create mode 100644 doc/users/next_whats_new/windows_arm64.rst

diff --git a/doc/users/next_whats_new/windows_arm64.rst b/doc/users/next_whats_new/windows_arm64.rst
new file mode 100644
index 000000000000..dcaf0e3b618a
--- /dev/null
+++ b/doc/users/next_whats_new/windows_arm64.rst
@@ -0,0 +1,8 @@
+Windows on Arm Support
+----------------------
+
+Preliminary support for windows on arm64 target added.
+
+Matplotlib for windows/arm64 requires FreeType 2.11 or above.
+
+No binary wheels are available yet but can be built from source.
\ No newline at end of file
diff --git a/setupext.py b/setupext.py
index e41ab98fe1c0..90bc304531b5 100644
--- a/setupext.py
+++ b/setupext.py
@@ -167,12 +167,21 @@ def get_and_extract_tarball(urls, sha, dirname):
         '955e17244e9b38adb0c98df66abb50467312e6bb70eac07e49ce6bd1a20e809a',
     '2.10.1':
         '3a60d391fd579440561bf0e7f31af2222bc610ad6ce4d9d7bd2165bca8669110',
+    '2.11.1':
+        'f8db94d307e9c54961b39a1cc799a67d46681480696ed72ecf78d4473770f09b'
 }
 # This is the version of FreeType to use when building a local version.  It
 # must match the value in lib/matplotlib.__init__.py and also needs to be
 # changed below in the embedded windows build script (grep for "REMINDER" in
 # this file). Also update the cache path in `.circleci/config.yml`.
-LOCAL_FREETYPE_VERSION = '2.6.1'
+TESTING_VERSION_OF_FREETYPE = '2.6.1'
+if sys.platform.startswith('win') and platform.machine() == 'ARM64':
+    # older versions of freetype are not supported for win/arm64
+    # Matplotlib tests will not pass
+    LOCAL_FREETYPE_VERSION = '2.11.1'
+else:
+    LOCAL_FREETYPE_VERSION = TESTING_VERSION_OF_FREETYPE
+
 LOCAL_FREETYPE_HASH = _freetype_hashes.get(LOCAL_FREETYPE_VERSION, 'unknown')
 
 # Also update the cache path in `.circleci/config.yml`.
@@ -646,9 +655,16 @@ def do_custom_build(self, env):
             subprocess.check_call([make], env=env, cwd=src_path)
         else:  # compilation on windows
             shutil.rmtree(src_path / "objs", ignore_errors=True)
-            msbuild_platform = (
-                'x64' if platform.architecture()[0] == '64bit' else 'Win32')
-            base_path = Path("build/freetype-2.6.1/builds/windows")
+            is_x64 = platform.architecture()[0] == '64bit'
+            if platform.machine() == 'ARM64':
+                msbuild_platform = 'ARM64'
+            elif is_x64:
+                msbuild_platform = 'x64'
+            else:
+                msbuild_platform = 'Win32'
+            base_path = Path(
+                f"build/freetype-{LOCAL_FREETYPE_VERSION}/builds/windows"
+            )
             vc = 'vc2010'
             sln_path = (
                 base_path / vc / "freetype.sln"
@@ -678,14 +694,29 @@ def do_custom_build(self, env):
 
             cc = get_ccompiler()
             cc.initialize()  # Get msbuild in the %PATH% of cc.spawn.
+            # Freetype 2.10.0+ support static builds.
+            msbuild_config = (
+                "Release Static"
+                if [*map(int, LOCAL_FREETYPE_VERSION.split("."))] >= [2, 10]
+                else "Release"
+            )
+
             cc.spawn(["msbuild", str(sln_path),
                       "/t:Clean;Build",
-                      f"/p:Configuration=Release;Platform={msbuild_platform}"])
+                      f"/p:Configuration={msbuild_config};"
+                      f"Platform={msbuild_platform}"])
             # Move to the corresponding Unix build path.
             (src_path / "objs" / ".libs").mkdir()
             # Be robust against change of FreeType version.
-            lib_path, = (src_path / "objs" / vc / msbuild_platform).glob(
-                "freetype*.lib")
+            lib_paths = Path(src_path / "objs").rglob('freetype*.lib')
+            # Select FreeType library for required platform
+            lib_path, = [
+                p for p in lib_paths
+                if msbuild_platform in p.resolve().as_uri()
+            ]
+            print(
+                f"Copying {lib_path} to {src_path}/objs/.libs/libfreetype.lib"
+            )
             shutil.copy2(lib_path, src_path / "objs/.libs/libfreetype.lib")