How to make find_package(Vulkan REQUIRED COMPONENTS shaderc_combined) work?

[jasjuang]

Something like the below doesn't work

vcpkg add port vulkan 
vcpkg add port shaderc
vcpkg install

find_package(Vulkan REQUIRED COMPONENTS shaderc_combined) still results in Could NOT find Vulkan (missing: shaderc_combined) (found version "1.4.304")
Checking the vcpkg.json of shaderc and there are no optional features to enable. Can someone please help?

[dg0yt]

AFAICT vcpkg doesn't want to see two librararies providing the same symbols. And shaderc's dependencies already install individual libs. Therefore port shaderc deliberate doesn't build+install the combined conveninence library.

vcpkg/ports/shaderc/fix-build-type.patch

Lines 70 to 78 in 984f923

	+if(0)
	shaderc_combine_static_lib(shaderc_combined shaderc)
	if(SHADERC_ENABLE_INSTALL)
	@@ -122,6 +131,7 @@ shaderc_add_tests(
	TEST_NAMES
	shaderc
	shaderc_cpp)
	+endif()

And no, this is not something which can be resolved with a feature.

However, the port provides an unofficial CMake config/target which should carry the necessary link libraries for convenience (but limited to vcpkg, unfortunately).

[jasjuang]

In my opinion, vcpkg shouldn't alter expected port behavior, this causes unnecessary confusion, increases friction for people using vcpkg, and makes it harder to convince people to use vcpkg.

There are tons of code out there that links to Vulkan and made use of shaderc_combined, and now I have to download the Vulkan SDK separately to work with their code instead of being able to nicely managing all dependencies in vcpkg.

Additionally, find_package(Vulkan REQUIRED COMPONENTS shaderc_combined) is from the official CMake itself, https://cmake.org/cmake/help/latest/module/FindVulkan.html, that means vcpkg is deliberately breaking functionality that is supposed to work from the official CMake code. How can this be a good idea?

What are the concerns of having two libraries providing the same symbols besides a little bit of extra disk space?

[dg0yt]

What are the concerns of having two libraries providing the same symbols besides a little bit of extra disk space?

It breaks autolinking for msbuild.

vcpkg shouldn't alter expected port behavior

That's the guiding line. But sometimes one package's isolated expected behaviour doesn't make sense as part of a wider integration.

Even if it isn't possible to add the lib, it might be possible to add sufficient shaderc_combined polyfill with a vcpkg cmake wrapper.

[jasjuang]

It doesn't seem very obvious to me on how to add sufficient shaderc_combined polyfill with a vcpkg cmake wrapper. How about enabling shaderc_combined first for non-Windows platforms?