CMake program target .elf path is wrong

[JeyRunner]

Hi,
I am trying to setup a new modm project with CMake as build script generator. When calling the programming target with make program I get the following error:

** Programming Started **
Error: couldn't open PATH_TO_PROJECT_FOLDER/app/build/src/rot_encoder.elf
embedded:startup.tcl:1516: Error: ** Programming Failed **
in procedure 'modm_program' 
in procedure 'program' called at file "modm/openocd.cfg", line 13
in procedure 'program_error' called at file "embedded:startup.tcl", line 1581
at file "embedded:startup.tcl", line 1516
Built target program

I have the following file structure

├── app
│   ├── build
│   │   ├── rot_encoder.bin
│   │   ├── rot_encoder.elf
│   ├── CMakeLists.txt
│   ├── modm
│   ├── project.xml
│   ├── scripts
│   │   └── prog.cfg
│   └── src
│       └── main.cpp
└── ext
    └── modm

The problem comes from

modm/tools/build_script_generator/cmake/resources/ModmConfiguration.cmake.in

Line 191 in ab7c1ca

${PROJECT_BINARY_DIR}/src/${project_name}.elf

When I change the line to the following it just works:

        ${PROJECT_BINARY_DIR}/${project_name}.elf   # removed src/

So my question is, am I doing something wrong? And why the .elf file is expected to be in a sub build/src/ folder and not directly in the build folder?

[salkinium]

I can reproduce this like so:

cd examples/stm32f469_discovery/assert/
lbuild -D ::build.path=build build
mkdir build
cd build
cmake ..
make -j4
make size

which then results in

 $ make size
Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "modm/examples/stm32f469_discovery/assert/modm/modm_tools/size.py", line 162, in <module>
    output = format(args.source, eval(args.memories))
  File "modm/examples/stm32f469_discovery/assert/modm/modm_tools/size.py", line 79, in format
    with open(source, "rb") as src:
         ~~~~^^^^^^^^^^^^^^
FileNotFoundError: [Errno 2] No such file or directory: '/Users/niklas/development/modm-dev/modm/examples/stm32f469_discovery/assert/build/src/assert.elf'
make[3]: *** [size] Error 1
make[2]: *** [CMakeFiles/size.dir/all] Error 2
make[1]: *** [CMakeFiles/size.dir/rule] Error 2
make: *** [size] Error 2
FAIL

I think that's just a bug introduced by some major refactorings to this module at some point.
With your proposed fix, it works fine for me. Please open a PR with your fix so you get proper credit.

[JeyRunner]

Thanks, @salkinium for verifying this.
I opened a pull request for the changes.
Since I am new to modm, I'm not sure if I missed something in the changes (hope that the CI will capture potential problems...).