HP aC++/HP C Programmer's Guide (B3901-90036; A.06.26; September 2011)

+O[no]aggressive

The +Oaggressive option enables aggressive optimizations. The +Onoaggressive

option disables aggressive optimizations.

By default, aggressive optimizations are turned off. The +Oaggressive option is

approximately equivalent to +Osignedpointers +Onoinitcheck

+Ofltacc=relaxed.

NOTE: This option is deprecated and may not be supported in future releases. Instead

you can use +Ofastoption.

+O[no]limit

The +Olimit option enables optimizations that significantly increase compile time or

that consume a lot of memory.

The +Onolimit option suppresses optimizations regardless of their effect on compile

time or memory consumption.

Use +Onolimit at all optimization levels.

Usage:

+O[no]limit=level

The defined values of level are:

default Based on tuning heuristics, the optimizer will spend a reasonable amount

of time processing large procedures. This is the default option.

min For large procedures, the optimizer will avoid non-linear time optimizations.

This option is a synonym for +Olimit.

none The optimizer will fully optimize large procedures, possibly resulting in

significantly increased compile time. This option is a synonym for

+Onolimit.

Example:

To remove optimization time restrictions at O2, O3, or O4 optimization levels, use

+Onolimit as follows:

aCC <opt level> +Onolimit sourcefile.C

+O[no]ptrs_to_globals[=list]

The +O[no]ptrs_to_globals option tells the optimizer whether global variables are

accessed [are not accessed] through pointers. If +Onoptrs_to_globals is specified, it is

assumed that statically-allocated data (including file-scoped globals, file-scoped statics,

68 Command-Line Options