@item -mthumb
This option specifies that the assembler should start assembling Thumb
instructions; that is, it should behave as though the file starts with a
@code{.code 16} directive.
@item -mthumb
This option specifies that the assembler should start assembling Thumb
instructions; that is, it should behave as though the file starts with a
@code{.code 16} directive.