win32: require MSVC ml to build MASM .asm file

Author: illwieckz

CMakeLists.txt

@@ -2,6 +2,10 @@ cmake_minimum_required(VERSION 3.28)
 
 project(native_client C CXX ASM)
 
+if (WIN32 AND NOT MINGW)
+	enable_language(ASM_MASM)
+endif()
+
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 
 include(DaemonPlatform/Platform)

src/trusted/service_runtime/CMakeLists.txt

@@ -103,8 +103,12 @@ elseif (ARCH STREQUAL "amd64")
 			# This use of win64_asm_env causes an invocation of MSVC, even if sel_ldr
 			# would not otherwise be actually built. So don't include it if we aren't
 			# actually building sel_ldr
-#TODO:		NACL_SWITCH_UNWIND_WIN_ASM = win64_asm_env.ComponentObject('arch/x86_64/nacl_switch_unwind_win.asm')
-#			list(APPEND LDR_INPUTS ${NACL_SWITCH_UNWIND_WIN_ASM})
+			if (MSVC)
+				add_library(nacl_switch_unwind_win OBJECT "arch/x86_64/nacl_switch_unwind_win.asm")
+				list(APPEND LDR_LIBS nacl_switch_unwind_win)
+			else()
+				message(WARNING "Cannot build nacl_switch_unwind_win without MSVC ml")
+			endif()
 		endif()
 	else()
 		list(APPEND LDR_INPUTS "arch/x86_64/sel_addrspace_posix_x86_64.c")
@@ -509,7 +513,6 @@ if (LINUX AND NOT BUILD_ELSEWHERE)
 		"${CMAKE_CURRENT_BINARY_DIR}/CMakeFiles/nacl_bootstrap.dir/linux/nacl_bootstrap.c.o"
 	)
 
-
 	add_custom_target(nacl_bootstrap_raw
 		COMMAND env CXX="${CMAKE_CXX_COMPILER}" "${PYTHON}"
 			${NACL_BOOTSTRAP_RAW_ARGS}