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

For more information on using Decimal FP, see the HP aC++/HP ANSI C Release Notes

section "Decimal floating-point arithmetic supported" under "New Features in the A.06.20

Release."

+FP

+FP[flags]

The +FP option specifies how the runtime environment for floating-point operations should

be initialized at program startup and used at link time. The default is that all trapping

behaviors are disabled.

The following flags are supported. Uppercase enables the flag, lowercase disables the

flag.

Table 4 Options for +FP[flags]

DescriptionFlag

Trap on invalid floating-point operations.V (v)

Trap on divide by zero.Z (z)

Trap on floating-point overflow.O (o)

Trap on floating-point underflow.U (u)

Trap on floating-point operations that produce inexact results.I (i)

Enable sudden underflow (flush to zero) of denormalized values.D (d)

To dynamically change these settings at runtime, see fesetenv(3M).

+FPmode

+FPmode specifies how the run-time environment for floating-point operations should be

initialized at program start up. By default, modes are as specified in the IEEE floating-point

standard: all traps disabled, gradual underflow, and rounding to nearest. See ld(1)

for specific values of mode. To dynamically change these settings at run time, refer to

fenv(5), fesettrapenable(3M), and fesetround(3M).

+O[no]libmerrno

Description:

The +O[no]libmerrno option enables [disables] support for errno in libm functions.

The default is +Onolibmerrno for C++, c99, or –AC99.

In C-mode, the default is +Olibmerrno with -Aa option.

50 Command-Line Options