Question about CMAKE_CXX_ABI_COMPILED Flag Variable

I am attempting to cross-compile gRPC (https://github.com/grpc/grpc) from Windows to Linux as a third-party dependency using CMake and the Clang compiler, and I am also attempting to link to a pre-compiled version of libc++.

Here is what I believe is the relevant section of my toolchain file:

set(CMAKE_CXX_ABI_COMPILED ON)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I${LIBCXX_DIR}/include/c++/v1")
add_compile_options(--target=${triple} --sysroot=${CMAKE_SYSROOT})

add_link_options(-v --target=${triple} --sysroot=${CMAKE_SYSROOT} -L${LIBCXX_DIR}/lib/Linux/${triple})

If I execute this, then I am able to compile and link successfully; however, the following line does not seem like it should be necessary: set(CMAKE_CXX_ABI_COMPILED ON). If I do not include this line in my toolchain file, then I get the following error:

-- Detecting CXX compiler ABI info - failed

Is it OK for me to set the CMAKE_CXX_ABI_COMPILED flag variable or am I masking an issue in my toolchain file? I am using cmake version 3.18.4.

Here is where I got the idea to implement this workaround in case it helps: https://github.com/ruslo/polly/issues/152.