HP aC++/HP C A.06.20 Programmer's Guide

+O[no]recovery

The +O[no]recovery option generates [does not generate] recovery code for control

speculation. The default is +Orecovery. For code that writes to uncacheable memory

that may not be properly identified as volatile, the +Orecovery option reduces the

risk of incorrect behavior.

NOTE: The program that uses signal handlers to catch signals raised by memory

accesses may not behave correctly under +Onorecovery.

+O[no]signedpointers

The +Osignedpointers option treats pointers in Boolean comparisons (for example,

<, <=, >, >=) as signed quantities. Applications that allocate shared memory and that

compare a pointer to shared memory with a pointer to private memory may run

incorrectly if this optimization is enabled.

The default is +Onosignedpointers.

NOTE: This option is supported in C-mode only. A warning is displayed in C++ when

this option is used.

+Oshortdata

+Oshortdata[=size]

All objects of [size] bytes or smaller are placed in the short data area, and references

to such data assume it resides in the short data area. Valid values of size are a decimal

number between 8 and 4,194,304 (4MB).

If no size is specified, all data is placed in the short data area. The default is

+Oshortdata=8.

NOTE: Using a value that is too big or without the optional size, possibly through

+Ofast, may give various linker fix up errors, if there is more than 4Mb of short data.

+O[no]store_ordering

The +O[no]store_ordering option preserves [does not preserve] the original

program order for stores to memory that is visible to multiple threads. This does not

imply strong ordering. The default is +Onostore_ordering.

Code Optimizing Options 83