tested on: HP-UX 11.31 ia64,
gcc 4.7.1(HP AllianceOne version)
gcc 4.2.3(http://hpux.connect.org.uk)
HP C/aC++
HP-UX defaults to use LP32 and it treats long as 32 bit (= 4 bytes).
This build forces LP64 for treating long as 64 bit.