In the (autogenerated) .mex file for a project, each peripheral reads something like this:
1.0.0
Notice the verbiage in the "description" attribute. For other peripheral this varies, but it is almost always something like a warning or an error message. The project compiles and runs fine.
Also related, if I try to add a new software component from the 'Peripherals view', all the currently unselected peripherals are marked with yellow exclamations, please see the attached screen shot. If I hover the mouse over them, I get the same message shown in the "description" attribute. Yet I am able to add them without any issues.
What are those warnings about?