Cannot start debugging
I still don't know what happend. I was trying to make a C++ project with CubeMX's gerenated project. I hint "convert to C++" on project preferences...
I just give up and created a project with OpenSTM32 wizard instead of trying to use the CubeMX generated. Now it's all working.
After that I created a project with OpenSTM wizard I just moved the openstm32-custom startup file and LinkerScript to my new project.