[CMake] INCLUDE_DIRECTORIES per *file*

[Yevgen Muntyan]

Hi there,

Recently there was a thread about INCLUDE_DIRECTORIES() where the 
solution was to
have it per directory, and also I recently asked how to convert a 
project with libtool convenience
libraries (see below). I was told to set compile flags on source files, 
which does work, but I also need
different include paths. Since it's source files for the same target, I 
can't have different subdirectories
for different files, and so INCLUDE_DIRECTORIES() won't work for me. Any 
idea on how
to achieve what I want? Why are include dirs so special anyway, why 
aren't they settable on
source files while compile flags are? The latter isn't the most 
interesting question though :)

The project is roughly as follows:

 top/
  subdir1/
   file1.c
   file2.c
  subdir2/
   file3.c
   file4.c

file1.c and file2.c get compiled with SUB1_CFLAGS (including -I flags) into libsub1.la,
file3.c and file4.c get compiled with SUB2_CFLAGS into libsub2.la,
libsub1.la and libsub2.la link into libfoolala.so/dll.

Thanks!
Yevgen