It appears that although an array of packed structures is done correctly, when a routine is called that references an element of said packed structures the compiler believes it to be word aligned.
-- Summary: odd sized packed structures, under ARM, cause lockup of application Product: gcc Version: 4.3.1 Status: UNCONFIRMED Severity: blocker Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: damon dot michaels at navico dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37954