SPARC GAS normally permits data to be misaligned. For example, it permits the
pseudo-op to be used on a byte boundary. However, the native SunOS assemblers issue an error when they see misaligned data.
option is not the default because gcc issues misaligned data pseudo-ops when it initializes certain packed data structures (structures defined using the
attribute). You may have to assemble with GAS in order to initialize packed data structures in your own code.