These ‘-m’ options are defined for the H8/300 implementations:
Shorten some address references at link time, when possible; uses the
linker option -relax. See ld and the H8/300, for a fuller description.
Generate code for the H8/300H.
Generate code for the H8S.
Generate code for the H8S and H8/300H in the normal mode. This switch
must be used either with -mh or -ms.
Generate code for the H8S/2600. This switch must be used with -ms.
Make int data 32 bits by default.
On the H8/300H and H8S, use the same alignment rules as for the H8/300.
The default for the H8/300H and H8S is to align longs and floats on
-malign-300 causes them to be aligned on 2-byte boundaries.
This option has no effect on the H8/300.