HP Fortran Programmer Guide (766160-001, March 2014)

Table 10 Values for the +FP option (continued)
MeaningValue
Trap on floating-point operations that produce inexact results. Inexact result traps may occur whenever
roundoff is necessary to produce the result. For example, the fraction 1.0/3.0 produces an inexact trap
because there is no exact floating-point representation for this fraction.
I
Enable sudden underflow (flush to zero) of denormalized values on those PA-RISC systems greater than version
1.0 that have implemented sudden underflow. (That is, +FPD enables sudden underflow only if it is available
D
on the processor that is used at run time.) Denormalized values are those values whose absolute value is very
close to zero. For IEEE single precision data types, the largest denormalized value is approximately equal
to 2-126. For IEEE double precision data types, such values are approximately equal to 2 -1022. Sudden
underflow will cause some floating-point applications to run faster, with a possible loss of numerical accuracy
on numbers very close to zero.
+fp_exceptionis a compile time flag. It causes a descriptive message and a procedure
traceback to be issued to standard error when the HP-UX signals listed in Table 2-5 are generated.
+[no]fp_exception
For a description of these signals, see signal(2) and signal(5) in the HP-UX Reference. For
information about floating-point exceptions and error handling, see the HP-UX Floating-Point
Guide.
You can also use the ON statement to write your own trap procedures. For information about
the syntax of the ON statement, see “Using the ON statement” (page 81).
The default,+nofp_exception , disables traceback information.
Table 11 Signals recognized by the +fp_exception option
MeaningSignal
Illegal instructionSIGILL
Floating-point exceptionSIGFPE
Bus error instructionSIGBUS
Segmentation violationSIGSEGV
Bad argument to system callSIGSYS
-g causes the compiler to generate information for use by the HP WDB debugger. The -goption
can be used to prepare code for debugging that has been compiled with optimization
options-O,-O1/+O1, , but not O3/+O3or higher.
-g
+getarg0and +getarg1control the behavior of the getarg intrinsic subroutine. +getarg0
requests the industry standard behavior for getarg, where an index value of zero causes the
-G
program name to be returned. HP’s FORTRAN 77 getarg intrinsic also implements this industry
standard convention. +getarg1is used to request non-standard behavior, where an index value
of one causes the program name to be returned (older releases of HP Fortran behaved in this
manner). The default is +getarg0.
gformat77 requests the FORTRAN 77 style of formatting a value of zero with the G edit
descriptor. Fortran 90 uses an F edit descriptor when the value being written is zero, while
FORTRAN 77 uses an E edit descriptor.
gformat77
+gprof prepares object code files for profiling with gprof. The default is +nogprof. gprofis
provided as part of the “HP-UX General Programming Tools” product; see gprof(1). The
-Goption can be used to perform the same function as +gprof.
+[no]gprof
+hugecommon instructs the compiler to place the specified COMMON block into a huge data
segment. The format for this option is: +hugecommon=name
+hugecommon
where name is the name of a COMMON block. By default, only COMMON blocks larger than
2 gigabytes are placed into huge data segments.
For example:
28 Compiling and linking