I have successfully built and exported a shared library of mine by following the approach of putting the compiler flags into a separate INTERFACE library, as suggested in the CMake tutorial.

I also need an exportable static version of my library but I am struggling to make the things work. Please consider the following CMakeFile.txt file that is a minimal reproducible example of my problem:

cmake_minimum_required(VERSION 3.21)

project(my_project LANGUAGES C)

# Example of interface library for compiler settings
add_library(compiler_flags INTERFACE)
target_compile_options(compiler_flags INTERFACE "-Wall")

# Real library
add_library(Foo STATIC foo.c) # It works with "SHARED" but not with "STATIC"
target_link_libraries(Foo PRIVATE compiler_flags) 

# Install the real library
install(TARGETS Foo EXPORT FooTargets)

# Install the configuration targets
install(
  EXPORT FooTargets
  NAMESPACE Foo::
  FILE FooTargets.cmake
  DESTINATION lib/cmake/Foo)

When I run cmake -B build, I get:

CMake Error: install(EXPORT "FooTargets" ...) includes target "Foo" which requires target "compiler_flags" that is not in any export set.

How can I make it work while keeping the compiler options in a separate INTERFACE library?

PS: I also looked at the static vs shared example in the official tutorial but, in that scenario, the static library is not directly exported (i.e., it is a private component of the exported shared library).