HP aC++/HP C A.06.28 Programmer's Guide Integrity servers (769150-001, March 2014)

Porting Options

Use the following options as necessary when porting your code from other operating environments

to HP-UX.

-fast

The -fast option selects a combination of optimization options for optimum execution speed and

reasonable build times. Currently chosen options are:

• +O2

• +Ofltacc=relaxed

• +Onolimit

• +DSnative

• +FPD

You can override any of the options in -fast by specifying a subsequent option after it. This

option is equivalent to +Ofast.

Use this option when porting C++ and C applications compiled on other UNIX operating systems

to HP-UX.

NOTE: Do not use this option for programs that depend on IEEE standard floating-point

denormalized numbers. Otherwise, different numerical results may occur.

+sb

The +sb option specifies unqualified char, short, int,long, and long long bitfields as

signed. The default is +sb.

NOTE: When both +sb and +uc are in effect, +uc will override this for char bit fields.

+ub

The +ub option specifies unqualified char, short, int, long, and long long bitfields as

unsigned. This option has no effect on signedness of enum bitfields or on signedness of non-bitfield

char. The default is +sb.

+uc

By default, all unqualified char data types are treated as signed char. Specifying +uc causes an

unqualified (plain) char data type to be treated as unsigned char. (Overloading and mangling

are unchanged.)

Use this option to help in porting applications from environments where an unqualified (plain)

char type is treated as unsigned char.

NOTE: Since all unqualified char types in the compilation unit will be affected by this option

(including those headers that define external and system interfaces), it is necessary to compile the

interfaces used in a single program uniformly.

70 Command-Line Options