Fix Windows i686 build

bindings/python/build/ffi.py

@@ -1,6 +1,7 @@
 """This script is run form setup.py (in the project root)"""
 
 import os
+import platform
 import sys
 from enum import Enum
 from pathlib import Path
@@ -69,6 +70,7 @@ class LinkMode(Enum):
 
     @staticmethod
     def from_env() -> "LinkMode":
+        """Read from the OXIDD_PYFFI_LINK_MODE environment variable"""
         if container_build:
             return LinkMode.STATIC
 
@@ -90,6 +92,12 @@ def from_env() -> "LinkMode":
             "`static`, `shared-system`, and `shared-dev`.",
         )
 
+    def crate_type(self) -> str:
+        """Associated Rust crate type"""
+        if self == LinkMode.STATIC:
+            return "staticlib"
+        return "cdylib"
+
 
 build_mode = LinkMode.from_env()
 
@@ -101,7 +109,21 @@ def from_env() -> "LinkMode":
     if build_mode != LinkMode.SHARED_SYSTEM:
         cargo_bin = which("cargo")
         print("building crates/oxidd-ffi ...")
-        run(cargo_bin, "build", f"--profile={profile}", "--package=oxidd-ffi")
+
+        # Fix win32 build on win64
+        cargo_additional_args = []
+        if platform.system() == "Windows" and sys.maxsize <= 0x1_0000_0000:
+            cargo_additional_args = ["--target=i686-pc-windows-msvc"]
+            lib_dir = target_dir / "i686-pc-windows-msvc" / profile
+
+        # Use --crate-type=... to avoid missing linker errors when cross-compiling
+        run(
+            cargo_bin,
+            "rustc",
+            f"--profile={profile}",
+            "--package=oxidd-ffi",
+            f"--crate-type={build_mode.crate_type()}",
+        )
 
     print("running cbindgen ...")
     run(
@@ -113,9 +135,8 @@ def from_env() -> "LinkMode":
 
 
 def read_cdefs(header: Path) -> str:
-    """
-    Remove C macros and include directives from the include header since CFFI cannot
-    deal with them.
+    """Remove C macros and include directives from the include header since CFFI
+    cannot deal with them.
     """
 
     res = ""