3.3 Options Summary

TABLE 5

Compiler Options Grouped by Functionality

Function

Option Flag

Compilation Mode:

Compile only; do not produce an executable file

-c

Show commands built by the driver but do not compile

-dryrun

Support Fortran 77 extensions and compatibility

-f77

Do not replace a module file whose content is not changed by the

-keepmod

compilation of the associated Fortran module

Retains the temporary files that are created during compilation.

-keeptmp

Specify path for writing compiled .mod Module files

-moddir=path

Specify name of object, library, or executable file to write

-o filename

Compile and generate only assembly code

-S

Strip symbol table from executable

-s

Suppress compiler messages, except error messages

-silent

Define path to directory for temporary files

-temp=path

Show elapsed time for each compilation phase

-time

Show version number of compiler and its phases

-V

Verbose messages

-v

Specify non-standard aliasing situations

-xalias=list

Compile with multiple processors

-xjobs=n

Generate make dependencies

-xM

Chapter 3 • Fortran Compiler Options

47

Function

Option Flag

(Oracle Solaris) Link debug information from object files into

-xs

executable

Compiled Code:

Add/suppress trailing underscores on external names

-ext_names=x

Inline specified user functions

-inline=list

Compile position independent code

-KPIC/-kpic

Inline certain math library routines

-libmil

(x86) Save copies of register-based function arguments in the stack

-preserve_argvalues

STOP returns integer status value to shell

-stop_status[=yn]

Specify code address space

-xcode=x

Equivalent to -inline

-xinline

Manually change the heuristics used by the compiler for deciding when

-xinline_param

to inline a function call

Generate a report written to standard output on the inlining of functions

-xinline_report

by the compiler

Enable prefetch instructions

-xprefetch[=x]

Specify use of optional registers

-xregs=x

Specify default data mappings

-xtypemap=x

Data Alignment:

Specify alignment of data in COMMON blocks

-aligncommon[=n]

Force COMMON block data alignment to allow double word fetch/

-dalign

store

Force alignment of all data on 8-byte boundaries

-dbl_align_all

Align COMMON block data on 8-byte boundaries

-f

Support file sharing between little-endian and big-endian platforms.

-xfilebyteorder

Specify memory alignment and behavior

-xmemalign[=ab]

Debugging:

Enable runtime subscript range checking

-C

Compile for debugging with dbx

-g

Flag use of undeclared variables

-u

Check !$PRAGMA ASSUME assertions

-xassume_control=check

Check for stack overflow at runtime

-xcheck=stkovf

Enable runtime task common check

-xcommonchk

Control compression of the debug section.

-xcompress

Specify format of compression of the debug section.

-xcompress_format

Control how much debugging and observability information is emitted

-xdebuginfo

Function

Option Flag

Compile for Performance Analyzer

-xF

Control globalization of file static variables but not functions

-xglobalize

Keep definitions of unreferenced functions and variables

-xkeep_unref

Enable debugging without object files

-xs

Diagnostics:

Flag use of non-standard extensions

-ansi

Suppress named warning messages

-erroff=

Display error tag names with error messages

-errtags

Show summary of compiler options

-flags, -help

Show version number of the compiler and its phases

-V

Verbose messages

-v

Verbose parallelization messages

-vpara

Show/suppress warning messages

-wn

(Oracle Solaris) Link debug information from object files into

-xs

executable

Linking and Libraries:

Allow/require dynamic/static libraries

-Bx

Allow only dynamic/static library linking

-dy, -dn

Build a dynamic (shared object) library

-G

-shared

Assign name to dynamic library

-hname

Add directory to library search path

-Lpath

Link with library libname.a or libname.so

-lname

Do not build library search path into executable.

-norunpath

Build runtime library search path into executable

-Rpath

Disable use of incremental linker, ild

-xildoff

Link with optimized math library

-xlibmopt

Reserve an area of memory before the start of each function

-xpatchpadding

Specify whether the program contains references to dynamically bound

-xunboundsym

symbols

Link editor option

-zx

Generate pure libraries with no relocations

-ztext

Numerics and Floating-Point:

Use non-standard floating-point preferences

-fnonstd

Select non-standard floating point

-fns

Chapter 3 • Fortran Compiler Options

49

Function

Option Flag

Enable runtime floating-point overflow during input

-fpover

Select IEEE floating-point rounding mode

-fround=r

Select floating-point optimization level

-fsimple=n

Select floating-point trapping mode

-ftrap=t

Specify rounding method for formatted input/output

-iorounding=mode

Promote single precision constants to double precision

-r8const

Optimization and Performance:

Analyze loops for data dependencies

-depend

Optimize using a selection of options

-fast

Control optimizations that impact interposing on global library

-fsemantic-interposition

functions.

-fno-semantic-interposition

Specify that the program does not perform I/O in more than one thread

-fserialio

at a time.

Specify optimization level

-On

Pad data layout for efficient use of cache

-pad[=p]

Allocate local variables on the memory stack

-stackvar

Enable loop unrolling

-unroll[=m]

Invoke interprocedural optimizations pass

-xipo[=n]

Reduce compile time by avoiding optimizations during the initial pass

-xipo_build

through the compiler, optimizing only at link time

Set highest optimization level for #pragma OPT

-xmaxopt[=n]

Enable/adjust compiler generated prefetch instructions

-xprefetch=list

Control automatic generation of prefetch instructions

-xprefetch_level=n

Enable generation or use of performance profiling data

-xprofile=p

Assert that no memory-based traps will occur

-xsafe=mem

Cause the driver to include a special mapfile on the link line.

-xsegment_align

Do no optimizations that increase code size

-xspace

Specify that the application will be run in situations where many

-xthroughput

processes are simultaneously running on the system

Generate calls to vector library functions automatically

-xvector[=yn]

Parallelization:

Enable automatic parallelization of DO loops

-autopar

Equivalent to -xopenmp=parallel

-fopenmp

Show loop parallelization information

-loopinfo

Compile for hand-coded multithreaded programming

-mt