7.142 --relaxed_ref_def, --no_relaxed_ref_def
Permits multiple object files to use tentative definitions of global variables.
Some traditional programs are written using this declaration style.
This option is primarily provided for compatibility with GNU C. ARM does not recommend
using this option for new application code.
The default is strict references and definitions. (Each
global variable can only be declared in one object file.)
This option is not available in C++.