A: This information is documented in the release notes but important enough to repeat.

Compiling files at optimization level 2 (-O or +O2) and above increases the amount of virtual memory needed by the compiler. In cases where very large functions or files are compiled at +O2, or in cases where aggressive (+O3 and above) optimization is used, ensure that the maxdsiz kernel tunable is set appropriately on the machine where compilation takes place.

HP recommends a setting of 0x80000000, or 2 Gb (the default for this parameter is 0x40000000, or 1 Gb) in such cases. Updating the maxdsiz tunable will ensure that the compiler does not run out of virtual memory when compiling large files or functions.

See the kctune man page for more information on how to change kernel tunable parameters.