Avoid MSVC ICE in nanobind's nb_func.h (#601)

CMakeLists.txt

@@ -287,6 +287,8 @@ if(BUILD_PYTHON)
                 git apply
                 ${CMAKE_CURRENT_SOURCE_DIR}/cmake/0001-Replace-zero-size-array.patch
                 ${CMAKE_CURRENT_SOURCE_DIR}/cmake/0002-Give-anonymous-union-a-name.patch
+                # https://github.com/wjakob/nanobind/issues/613
+                ${CMAKE_CURRENT_SOURCE_DIR}/cmake/0003-Avoid-MSVC-ICE-in-nb_func.h.patch
             UPDATE_DISCONNECTED 1
         )
         fetchcontent_makeavailable(nanobind)

cmake/0001-Replace-zero-size-array.patch

@@ -1,7 +1,7 @@
 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
 From: Tyler Veness <calcmogul@gmail.com>
 Date: Sat, 6 Jul 2024 14:27:32 -0700
-Subject: [PATCH 1/2] Replace zero-size array
+Subject: [PATCH 1/3] Replace zero-size array
 
 ---
  include/nanobind/nb_attr.h | 6 ------

cmake/0002-Give-anonymous-union-a-name.patch

@@ -1,7 +1,7 @@
 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
 From: Tyler Veness <calcmogul@gmail.com>
 Date: Sat, 6 Jul 2024 14:31:24 -0700
-Subject: [PATCH 2/2] Give anonymous union a name
+Subject: [PATCH 2/3] Give anonymous union a name
 
 ---
  include/nanobind/nb_class.h |  2 +-

cmake/0003-Avoid-MSVC-ICE-in-nb_func.h.patch

@@ -0,0 +1,38 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Tyler Veness <calcmogul@gmail.com>
+Date: Fri, 19 Jul 2024 12:08:44 -0700
+Subject: [PATCH 3/3] Avoid MSVC ICE in nb_func.h
+
+---
+ include/nanobind/nb_func.h | 10 ++++++++++
+ 1 file changed, 10 insertions(+)
+
+diff --git a/include/nanobind/nb_func.h b/include/nanobind/nb_func.h
+index e53e1a42cc94e73ad882af05ff269d4b92d11433..58aef31ad9f6aedf63a9f5751cf695f6d9c28927 100644
+--- a/include/nanobind/nb_func.h
++++ b/include/nanobind/nb_func.h
+@@ -199,14 +199,24 @@ NB_INLINE PyObject *func_create(Func &&func, Return (*)(Args...),
+
+         PyObject *result;
+         if constexpr (std::is_void_v<Return>) {
++#ifdef _MSC_VER
++            cap->func(static_cast<cast_t<Args>>(in.template get<Is>())...);
++#else
+             cap->func(in.template get<Is>().operator cast_t<Args>()...);
++#endif
+             result = Py_None;
+             Py_INCREF(result);
+         } else {
++#ifdef _MSC_VER
++            result = cast_out::from_cpp(
++                       cap->func(static_cast<cast_t<Args>>(in.template get<Is>())...),
++                       policy, cleanup).ptr();
++#else
+             result = cast_out::from_cpp(
+                        cap->func((in.template get<Is>())
+                                      .operator cast_t<Args>()...),
+                        policy, cleanup).ptr();
++#endif
+         }
+
+         if constexpr (Info::keep_alive)

pyproject.toml

@@ -44,13 +44,6 @@ install_args = [ ]
   BUILD_TESTING = "OFF"
   BUILD_PYTHON = "ON"
 
-  # https://github.com/wjakob/nanobind/issues/613
-  #
-  # Visual Studio 17.10.4's MSVC compiler gives an ICE in nanobind's nb_func.h,
-  # but clang-cl does not.
-  [tool.py-build-cmake.windows.cmake.options]
-  CMAKE_GENERATOR_TOOLSET = "ClangCl"
-
 [tool.pytest.ini_options]
 minversion = "6.0"
 testpaths = [ "jormungandr/test", "examples/CurrentManager/test" ]