cmake targets not update after reconfigure

my cmake projects allow certain targets to be switched by depending on cmake configurations.
something like:

option( FOO "" ON )

if (FOO)
  add_executable(bar)
endif()

with qtcreator 5.0, i'm seeing the following behaviour:

• the locator bar is up to date: if FOO==OFF, then `cm` does not list the target bar
• the "projects -> run settings" page however still lists `bar`, if `FOO==OFF`
• the target selector (the icon above the "RUN" icon) also lists `bar`, if `FOO==OFF`

this is a bit confusing, as a user can select targets, which are not available anymore and the target list is rather bloated (in my cases i end up with dozens of non-existent targets)