[CMake] project() with ASM fails with MSVC 19

[Robert Dailey]

Using CMake 3.9, I do this:

cmake_minimum_required(VERSION 3.9)
project(libpng VERSION 1.6.33 LANGUAGES ASM C)

I get the following error:

-- The ASM compiler identification is unknown
-- Didn't find assembler
-- The C compiler identification is MSVC 19.11.25507.1
CMake Error at CMakeLists.txt:16 (project):
No CMAKE_ASM_COMPILER could be found.


Why doesn't this work?