Try generating the .dll.a file for clangarm64

Author: oscarbenjamin

bin/cibw_before_build_windows_arm64.sh

@@ -0,0 +1,91 @@
+#!/bin/bash
+
+set -o errexit
+
+repo_root=$(python -c 'from pathlib import Path; print(Path.cwd().resolve().as_posix())')
+lib_dir="$repo_root/.local/lib"
+pkgconfig_dir="$lib_dir/pkgconfig"
+mkdir -p "$pkgconfig_dir"
+
+dll_name=$(python -c 'import sysconfig; print(sysconfig.get_config_var("LDLIBRARY") or "")')
+pkg_version=$(python -c 'import sysconfig; print(sysconfig.get_config_var("LDVERSION") or sysconfig.get_python_version())')
+include_dir=$(python -c 'import sysconfig; print(sysconfig.get_config_var("INCLUDEPY") or "")')
+base_prefix=$(python -c 'import sys; print(getattr(sys, "base_prefix", sys.prefix))')
+python_bin=$(python -c 'import os, sys; print(os.path.dirname(sys.executable))')
+
+include_dir=${include_dir//\\//}
+base_prefix=${base_prefix//\\//}
+python_bin=${python_bin//\\//}
+
+if [ -z "$dll_name" ] || [ -z "$include_dir" ]; then
+    echo "Could not determine Python DLL or include dir" >&2
+    exit 1
+fi
+
+dll_path=""
+for candidate in \
+    "$python_bin/$dll_name" \
+    "$base_prefix/$dll_name" \
+    "$base_prefix/DLLs/$dll_name" \
+    "$base_prefix/libs/$dll_name"
+do
+    if [ -f "$candidate" ]; then
+        dll_path="$candidate"
+        break
+    fi
+done
+
+if [ -z "$dll_path" ]; then
+    echo "Could not find $dll_name" >&2
+    exit 1
+fi
+
+if ! command -v gendef >/dev/null 2>&1; then
+    echo "Could not find gendef on PATH" >&2
+    exit 1
+fi
+
+if command -v cc >/dev/null 2>&1; then
+    dlltool=$(cc -print-prog-name=dlltool)
+fi
+if [ -n "${dlltool:-}" ] && [ -x "$dlltool" ]; then
+    :
+elif [ -n "${dlltool:-}" ] && command -v "$dlltool" >/dev/null 2>&1; then
+    dlltool=$(command -v "$dlltool")
+elif command -v dlltool >/dev/null 2>&1; then
+    dlltool=$(command -v dlltool)
+elif command -v llvm-dlltool >/dev/null 2>&1; then
+    dlltool=$(command -v llvm-dlltool)
+else
+    echo "Could not find dlltool or llvm-dlltool on PATH" >&2
+    exit 1
+fi
+
+dll_stem=${dll_name%.dll}
+def_path="$lib_dir/$dll_stem.def"
+import_lib="$lib_dir/lib$dll_stem.dll.a"
+pc_path="$pkgconfig_dir/python-$pkg_version.pc"
+
+rm -f "$def_path" "$import_lib"
+(
+    cd "$lib_dir"
+    gendef "$dll_path"
+)
+"$dlltool" -d "$def_path" -D "$dll_name" -l "$import_lib"
+
+printf 'prefix=%s\n' "$repo_root" > "$pc_path"
+printf 'exec_prefix=${prefix}\n' >> "$pc_path"
+printf 'libdir=%s\n' "$lib_dir" >> "$pc_path"
+printf 'includedir=%s\n\n' "$include_dir" >> "$pc_path"
+printf 'Name: Python\n' >> "$pc_path"
+printf 'Description: CPython import library for MinGW wheel builds\n' >> "$pc_path"
+printf 'Version: %s\n' "$pkg_version" >> "$pc_path"
+printf 'Libs: -L${libdir} -l%s\n' "$dll_stem" >> "$pc_path"
+printf 'Cflags: -I${includedir}\n' >> "$pc_path"
+
+if command -v pkg-config >/dev/null 2>&1; then
+    pkg-config --exists "python-$pkg_version"
+fi
+
+echo "Generated $import_lib"
+echo "Generated $pc_path"

meson.build

@@ -77,6 +77,14 @@ endif
 
 pyflint_deps = [gmp_dep, mpfr_dep, flint_dep]
 
+# Meson's Windows sysconfig dependency path can hand the clangarm64
+# toolchain the python DLL itself. Use pkg-config on Windows ARM64 so we can
+# provide a MinGW import library instead.
+if host_machine.system() == 'windows' and host_machine.cpu_family() in ['aarch64', 'arm64'] and cc.get_id() in ['gcc', 'clang']
+  dep_py = py.dependency(method: 'pkg-config')
+  pyflint_deps = [dep_py] + pyflint_deps
+endif
+
 add_project_arguments(
     '-X', 'embedsignature=True',
     '-X', 'emit_code_comments=True',

pyproject.toml

@@ -176,3 +176,7 @@ repair-wheel-command = [
 """,
 "delvewheel repair -w {dest_dir} {wheel} --add-path .local/bin",
 ]
+
+[[tool.cibuildwheel.overrides]]
+select = ["*-win_arm64"]
+before-build = "C:\\msys64\\usr\\bin\\bash bin/cibw_before_build_windows_arm64.sh && pip install wheel delvewheel"