------- Comment #4 from schwab at linux-m68k dot org 2010-06-10 10:12 ------- You need to use the %U and %X modifiers together with "m". If the insn does not support them (no update and/or indexed form) you cannot use "m". Basically this means you can use "m" only with the normal load/store insns.
-- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44492