[cmake-developers] target_include_directories is broken with ninja generator

[Matthew Woehlke]

This simple CMakeLists.txt is broken with ninja:

cmake_minimum_required(VERSION 2.8.10.20130312)
project(Foo)

add_executable(foo foo.cpp)

target_include_directories(foo PUBLIC
   $<BUILD_INTERFACE:${Foo_BINARY_DIR}>
   $<INSTALL_INTERFACE:${CMAKE_INSTALL_PREFIX}/include>
)

...with Ninja, the include directive passed to the compiler is '-I.' 
(with the binary dir prefix similarly stripped for anything after the ${}).

It seems okay with the Makefile generator.

This does appear to be a CMake problem, and not a ninja problem, as in 
the build.ninja I am seeing 'FLAGS = -I.'.

It would be nice to have this fixed before 2.8.11 final :-).

(Note: I haven't yet checked if the installed exports file is okay, 
since this is preventing my project from building, although presumably 
that is at least not generator dependent.)

-- 
Matthew