To have the iropt subcommand to be called by the compiler, that would be at least "CC -O2". eg:
CC -O2 -g -xarch=v9 file.c -o test64
CC -O2 -g file.c -o test32
To have the iropt subcommand to be called by the compiler, that would be at least "CC -O2". eg:
CC -O2 -g -xarch=v9 file.c -o test64
CC -O2 -g file.c -o test32