Handling header files dependencies with cmake

Question

I am using CMake on a small C++ project and so far it works great... with one twist :x

When I change a header file, it typically requires recompiling a number of sou

Answer 1

I just hit the same issue. After changing paths in include_directories() from absolute to relative it added appropriate dependencies.

Looks like CMake tries to guess which headers are system and which are project related. I suspect that directories that starts with / passed as -isystem /some/path and thus are not presented in generated dependencies.

If you can't replace ${FOO_SOURCE_DIR} with relative path you can try to calculate relative path using appropriate CMake functions. I.e.:

file(RELATIVE_PATH FOO_SOURCE_REL_DIR
     ${CMAKE_CURRENT_SOURCE_DIR}
     ${FOO_SOURCE_DIR}/.)
include_directories(${FOO_SOURCE_REL_DIR}/include)