1479 lines
68 KiB
Groff
1479 lines
68 KiB
Groff
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.ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
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. \" corrections for vroff
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.if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
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. \" for low resolution devices (crt and lpr)
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\{\
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.\}
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.rm #[ #] #H #V #F C
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|
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.\" ========================================================================
|
||
|
|
.\"
|
||
|
|
.IX Title "GFORTRAN 1"
|
||
|
|
.TH GFORTRAN 1 "2017-01-09" "gcc-6.3.1" "GNU"
|
||
|
|
.\" For nroff, turn off justification. Always turn off hyphenation; it makes
|
||
|
|
.\" way too many mistakes in technical documents.
|
||
|
|
.if n .ad l
|
||
|
|
.nh
|
||
|
|
.SH "NAME"
|
||
|
|
gfortran \- GNU Fortran compiler
|
||
|
|
.SH "SYNOPSIS"
|
||
|
|
.IX Header "SYNOPSIS"
|
||
|
|
gfortran [\fB\-c\fR|\fB\-S\fR|\fB\-E\fR]
|
||
|
|
[\fB\-g\fR] [\fB\-pg\fR] [\fB\-O\fR\fIlevel\fR]
|
||
|
|
[\fB\-W\fR\fIwarn\fR...] [\fB\-pedantic\fR]
|
||
|
|
[\fB\-I\fR\fIdir\fR...] [\fB\-L\fR\fIdir\fR...]
|
||
|
|
[\fB\-D\fR\fImacro\fR[=\fIdefn\fR]...] [\fB\-U\fR\fImacro\fR]
|
||
|
|
[\fB\-f\fR\fIoption\fR...]
|
||
|
|
[\fB\-m\fR\fImachine-option\fR...]
|
||
|
|
[\fB\-o\fR \fIoutfile\fR] \fIinfile\fR...
|
||
|
|
.PP
|
||
|
|
Only the most useful options are listed here; see below for the
|
||
|
|
remainder.
|
||
|
|
.SH "DESCRIPTION"
|
||
|
|
.IX Header "DESCRIPTION"
|
||
|
|
The \fBgfortran\fR command supports all the options supported by the
|
||
|
|
\&\fBgcc\fR command. Only options specific to \s-1GNU\s0 Fortran are documented
|
||
|
|
here.
|
||
|
|
.PP
|
||
|
|
All \s-1GCC\s0 and \s-1GNU\s0 Fortran options
|
||
|
|
are accepted both by \fBgfortran\fR and by \fBgcc\fR
|
||
|
|
(as well as any other drivers built at the same time,
|
||
|
|
such as \fBg++\fR),
|
||
|
|
since adding \s-1GNU\s0 Fortran to the \s-1GCC\s0 distribution
|
||
|
|
enables acceptance of \s-1GNU\s0 Fortran options
|
||
|
|
by all of the relevant drivers.
|
||
|
|
.PP
|
||
|
|
In some cases, options have positive and negative forms;
|
||
|
|
the negative form of \fB\-ffoo\fR would be \fB\-fno\-foo\fR.
|
||
|
|
This manual documents only one of these two forms, whichever
|
||
|
|
one is not the default.
|
||
|
|
.SH "OPTIONS"
|
||
|
|
.IX Header "OPTIONS"
|
||
|
|
Here is a summary of all the options specific to \s-1GNU\s0 Fortran, grouped
|
||
|
|
by type. Explanations are in the following sections.
|
||
|
|
.IP "\fIFortran Language Options\fR" 4
|
||
|
|
.IX Item "Fortran Language Options"
|
||
|
|
\&\fB\-fall\-intrinsics \-fbackslash \-fcray\-pointer \-fd\-lines\-as\-code
|
||
|
|
\&\-fd\-lines\-as\-comments
|
||
|
|
\&\-fdec \-fdec\-structure \-fdefault\-double\-8 \-fdefault\-integer\-8
|
||
|
|
\&\-fdefault\-real\-8 \-fdollar\-ok \-ffixed\-line\-length\-\fR\fIn\fR
|
||
|
|
\&\fB\-ffixed\-line\-length\-none \-ffree\-form \-ffree\-line\-length\-\fR\fIn\fR
|
||
|
|
\&\fB\-ffree\-line\-length\-none \-fimplicit\-none \-finteger\-4\-integer\-8
|
||
|
|
\&\-fmax\-identifier\-length \-fmodule\-private \-ffixed\-form \-fno\-range\-check
|
||
|
|
\&\-fopenacc \-fopenmp \-freal\-4\-real\-10 \-freal\-4\-real\-16 \-freal\-4\-real\-8
|
||
|
|
\&\-freal\-8\-real\-10 \-freal\-8\-real\-16 \-freal\-8\-real\-4 \-std=\fR\fIstd\fR\fB \fR
|
||
|
|
.IP "\fIPreprocessing Options\fR" 4
|
||
|
|
.IX Item "Preprocessing Options"
|
||
|
|
\&\fB\-A\-\fR\fIquestion\fR[\fB=\fR\fIanswer\fR]
|
||
|
|
\&\fB\-A\fR\fIquestion\fR\fB=\fR\fIanswer\fR \fB\-C \-CC \-D\fR\fImacro\fR[\fB=\fR\fIdefn\fR]
|
||
|
|
\&\fB\-H \-P
|
||
|
|
\&\-U\fR\fImacro\fR \fB\-cpp \-dD \-dI \-dM \-dN \-dU \-fworking\-directory
|
||
|
|
\&\-imultilib\fR \fIdir\fR
|
||
|
|
\&\fB\-iprefix\fR \fIfile\fR \fB\-iquote \-isysroot\fR \fIdir\fR \fB\-isystem\fR \fIdir\fR \fB\-nocpp
|
||
|
|
\&\-nostdinc
|
||
|
|
\&\-undef\fR
|
||
|
|
.IP "\fIError and Warning Options\fR" 4
|
||
|
|
.IX Item "Error and Warning Options"
|
||
|
|
\&\fB\-Waliasing \-Wall \-Wampersand \-Warray\-bounds
|
||
|
|
\&\-Wc\-binding\-type \-Wcharacter\-truncation
|
||
|
|
\&\-Wconversion \-Wfunction\-elimination \-Wimplicit\-interface
|
||
|
|
\&\-Wimplicit\-procedure \-Wintrinsic\-shadow \-Wuse\-without\-only \-Wintrinsics\-std
|
||
|
|
\&\-Wline\-truncation \-Wno\-align\-commons \-Wno\-tabs \-Wreal\-q\-constant
|
||
|
|
\&\-Wsurprising \-Wunderflow \-Wunused\-parameter \-Wrealloc\-lhs \-Wrealloc\-lhs\-all
|
||
|
|
\&\-Wtarget\-lifetime \-fmax\-errors=\fR\fIn\fR \fB\-fsyntax\-only \-pedantic \-pedantic\-errors\fR
|
||
|
|
.IP "\fIDebugging Options\fR" 4
|
||
|
|
.IX Item "Debugging Options"
|
||
|
|
\&\fB\-fbacktrace \-fdump\-fortran\-optimized \-fdump\-fortran\-original
|
||
|
|
\&\-fdump\-parse\-tree \-ffpe\-trap=\fR\fIlist\fR \fB\-ffpe\-summary=\fR\fIlist\fR\fB \fR
|
||
|
|
.IP "\fIDirectory Options\fR" 4
|
||
|
|
.IX Item "Directory Options"
|
||
|
|
\&\fB\-I\fR\fIdir\fR \fB\-J\fR\fIdir\fR \fB\-fintrinsic\-modules\-path\fR \fIdir\fR
|
||
|
|
.IP "\fILink Options\fR" 4
|
||
|
|
.IX Item "Link Options"
|
||
|
|
\&\fB\-static\-libgfortran\fR
|
||
|
|
.IP "\fIRuntime Options\fR" 4
|
||
|
|
.IX Item "Runtime Options"
|
||
|
|
\&\fB\-fconvert=\fR\fIconversion\fR \fB\-fmax\-subrecord\-length=\fR\fIlength\fR
|
||
|
|
\&\fB\-frecord\-marker=\fR\fIlength\fR \fB\-fsign\-zero\fR
|
||
|
|
.IP "\fICode Generation Options\fR" 4
|
||
|
|
.IX Item "Code Generation Options"
|
||
|
|
\&\fB\-faggressive\-function\-elimination \-fblas\-matmul\-limit=\fR\fIn\fR
|
||
|
|
\&\fB\-fbounds\-check \-fcheck\-array\-temporaries
|
||
|
|
\&\-fcheck=\fR\fI<all|array\-temps|bounds|do|mem|pointer|recursion>\fR
|
||
|
|
\&\fB\-fcoarray=\fR\fI<none|single|lib>\fR \fB\-fexternal\-blas \-ff2c
|
||
|
|
\&\-ffrontend\-optimize
|
||
|
|
\&\-finit\-character=\fR\fIn\fR \fB\-finit\-integer=\fR\fIn\fR \fB\-finit\-local\-zero
|
||
|
|
\&\-finit\-logical=\fR\fI<true|false>\fR
|
||
|
|
\&\fB\-finit\-real=\fR\fI<zero|inf|\-inf|nan|snan>\fR
|
||
|
|
\&\fB\-finline\-matmul\-limit=\fR\fIn\fR
|
||
|
|
\&\fB\-fmax\-array\-constructor=\fR\fIn\fR \fB\-fmax\-stack\-var\-size=\fR\fIn\fR
|
||
|
|
\&\fB\-fno\-align\-commons
|
||
|
|
\&\-fno\-automatic \-fno\-protect\-parens \-fno\-underscoring
|
||
|
|
\&\-fsecond\-underscore \-fpack\-derived \-frealloc\-lhs \-frecursive
|
||
|
|
\&\-frepack\-arrays \-fshort\-enums \-fstack\-arrays\fR
|
||
|
|
.SS "Options controlling Fortran dialect"
|
||
|
|
.IX Subsection "Options controlling Fortran dialect"
|
||
|
|
The following options control the details of the Fortran dialect
|
||
|
|
accepted by the compiler:
|
||
|
|
.IP "\fB\-ffree\-form\fR" 4
|
||
|
|
.IX Item "-ffree-form"
|
||
|
|
.PD 0
|
||
|
|
.IP "\fB\-ffixed\-form\fR" 4
|
||
|
|
.IX Item "-ffixed-form"
|
||
|
|
.PD
|
||
|
|
Specify the layout used by the source file. The free form layout
|
||
|
|
was introduced in Fortran 90. Fixed form was traditionally used in
|
||
|
|
older Fortran programs. When neither option is specified, the source
|
||
|
|
form is determined by the file extension.
|
||
|
|
.IP "\fB\-fall\-intrinsics\fR" 4
|
||
|
|
.IX Item "-fall-intrinsics"
|
||
|
|
This option causes all intrinsic procedures (including the GNU-specific
|
||
|
|
extensions) to be accepted. This can be useful with \fB\-std=f95\fR to
|
||
|
|
force standard-compliance but get access to the full range of intrinsics
|
||
|
|
available with \fBgfortran\fR. As a consequence, \fB\-Wintrinsics\-std\fR
|
||
|
|
will be ignored and no user-defined procedure with the same name as any
|
||
|
|
intrinsic will be called except when it is explicitly declared \f(CW\*(C`EXTERNAL\*(C'\fR.
|
||
|
|
.IP "\fB\-fd\-lines\-as\-code\fR" 4
|
||
|
|
.IX Item "-fd-lines-as-code"
|
||
|
|
.PD 0
|
||
|
|
.IP "\fB\-fd\-lines\-as\-comments\fR" 4
|
||
|
|
.IX Item "-fd-lines-as-comments"
|
||
|
|
.PD
|
||
|
|
Enable special treatment for lines beginning with \f(CW\*(C`d\*(C'\fR or \f(CW\*(C`D\*(C'\fR
|
||
|
|
in fixed form sources. If the \fB\-fd\-lines\-as\-code\fR option is
|
||
|
|
given they are treated as if the first column contained a blank. If the
|
||
|
|
\&\fB\-fd\-lines\-as\-comments\fR option is given, they are treated as
|
||
|
|
comment lines.
|
||
|
|
.IP "\fB\-fdec\fR" 4
|
||
|
|
.IX Item "-fdec"
|
||
|
|
\&\s-1DEC\s0 compatibility mode. Enables extensions and other features that mimic
|
||
|
|
the default behavior of older compilers (such as \s-1DEC\s0).
|
||
|
|
These features are non-standard and should be avoided at all costs.
|
||
|
|
For details on \s-1GNU\s0 Fortran's implementation of these extensions see the
|
||
|
|
full documentation.
|
||
|
|
.Sp
|
||
|
|
Other flags enabled by this switch are:
|
||
|
|
\&\fB\-fdollar\-ok\fR \fB\-fcray\-pointer\fR \fB\-fdec\-structure\fR
|
||
|
|
.IP "\fB\-fdec\-structure\fR" 4
|
||
|
|
.IX Item "-fdec-structure"
|
||
|
|
Enable \s-1DEC \s0\f(CW\*(C`STRUCTURE\*(C'\fR and \f(CW\*(C`RECORD\*(C'\fR as well as \f(CW\*(C`UNION\*(C'\fR,
|
||
|
|
\&\f(CW\*(C`MAP\*(C'\fR, and dot ('.') as a member separator (in addition to '%'). This is
|
||
|
|
provided for compatibility only; Fortran 90 derived types should be used
|
||
|
|
instead where possible.
|
||
|
|
.IP "\fB\-fdollar\-ok\fR" 4
|
||
|
|
.IX Item "-fdollar-ok"
|
||
|
|
Allow \fB$\fR as a valid non-first character in a symbol name. Symbols
|
||
|
|
that start with \fB$\fR are rejected since it is unclear which rules to
|
||
|
|
apply to implicit typing as different vendors implement different rules.
|
||
|
|
Using \fB$\fR in \f(CW\*(C`IMPLICIT\*(C'\fR statements is also rejected.
|
||
|
|
.IP "\fB\-fbackslash\fR" 4
|
||
|
|
.IX Item "-fbackslash"
|
||
|
|
Change the interpretation of backslashes in string literals from a single
|
||
|
|
backslash character to \*(L"C\-style\*(R" escape characters. The following
|
||
|
|
combinations are expanded \f(CW\*(C`\ea\*(C'\fR, \f(CW\*(C`\eb\*(C'\fR, \f(CW\*(C`\ef\*(C'\fR, \f(CW\*(C`\en\*(C'\fR,
|
||
|
|
\&\f(CW\*(C`\er\*(C'\fR, \f(CW\*(C`\et\*(C'\fR, \f(CW\*(C`\ev\*(C'\fR, \f(CW\*(C`\e\e\*(C'\fR, and \f(CW\*(C`\e0\*(C'\fR to the \s-1ASCII\s0
|
||
|
|
characters alert, backspace, form feed, newline, carriage return,
|
||
|
|
horizontal tab, vertical tab, backslash, and \s-1NUL,\s0 respectively.
|
||
|
|
Additionally, \f(CW\*(C`\ex\*(C'\fR\fInn\fR, \f(CW\*(C`\eu\*(C'\fR\fInnnn\fR and
|
||
|
|
\&\f(CW\*(C`\eU\*(C'\fR\fInnnnnnnn\fR (where each \fIn\fR is a hexadecimal digit) are
|
||
|
|
translated into the Unicode characters corresponding to the specified code
|
||
|
|
points. All other combinations of a character preceded by \e are
|
||
|
|
unexpanded.
|
||
|
|
.IP "\fB\-fmodule\-private\fR" 4
|
||
|
|
.IX Item "-fmodule-private"
|
||
|
|
Set the default accessibility of module entities to \f(CW\*(C`PRIVATE\*(C'\fR.
|
||
|
|
Use-associated entities will not be accessible unless they are explicitly
|
||
|
|
declared as \f(CW\*(C`PUBLIC\*(C'\fR.
|
||
|
|
.IP "\fB\-ffixed\-line\-length\-\fR\fIn\fR" 4
|
||
|
|
.IX Item "-ffixed-line-length-n"
|
||
|
|
Set column after which characters are ignored in typical fixed-form
|
||
|
|
lines in the source file, and through which spaces are assumed (as
|
||
|
|
if padded to that length) after the ends of short fixed-form lines.
|
||
|
|
.Sp
|
||
|
|
Popular values for \fIn\fR include 72 (the
|
||
|
|
standard and the default), 80 (card image), and 132 (corresponding
|
||
|
|
to \*(L"extended-source\*(R" options in some popular compilers).
|
||
|
|
\&\fIn\fR may also be \fBnone\fR, meaning that the entire line is meaningful
|
||
|
|
and that continued character constants never have implicit spaces appended
|
||
|
|
to them to fill out the line.
|
||
|
|
\&\fB\-ffixed\-line\-length\-0\fR means the same thing as
|
||
|
|
\&\fB\-ffixed\-line\-length\-none\fR.
|
||
|
|
.IP "\fB\-ffree\-line\-length\-\fR\fIn\fR" 4
|
||
|
|
.IX Item "-ffree-line-length-n"
|
||
|
|
Set column after which characters are ignored in typical free-form
|
||
|
|
lines in the source file. The default value is 132.
|
||
|
|
\&\fIn\fR may be \fBnone\fR, meaning that the entire line is meaningful.
|
||
|
|
\&\fB\-ffree\-line\-length\-0\fR means the same thing as
|
||
|
|
\&\fB\-ffree\-line\-length\-none\fR.
|
||
|
|
.IP "\fB\-fmax\-identifier\-length=\fR\fIn\fR" 4
|
||
|
|
.IX Item "-fmax-identifier-length=n"
|
||
|
|
Specify the maximum allowed identifier length. Typical values are
|
||
|
|
31 (Fortran 95) and 63 (Fortran 2003 and Fortran 2008).
|
||
|
|
.IP "\fB\-fimplicit\-none\fR" 4
|
||
|
|
.IX Item "-fimplicit-none"
|
||
|
|
Specify that no implicit typing is allowed, unless overridden by explicit
|
||
|
|
\&\f(CW\*(C`IMPLICIT\*(C'\fR statements. This is the equivalent of adding
|
||
|
|
\&\f(CW\*(C`implicit none\*(C'\fR to the start of every procedure.
|
||
|
|
.IP "\fB\-fcray\-pointer\fR" 4
|
||
|
|
.IX Item "-fcray-pointer"
|
||
|
|
Enable the Cray pointer extension, which provides C\-like pointer
|
||
|
|
functionality.
|
||
|
|
.IP "\fB\-fopenacc\fR" 4
|
||
|
|
.IX Item "-fopenacc"
|
||
|
|
Enable the OpenACC extensions. This includes OpenACC \f(CW\*(C`!$acc\*(C'\fR
|
||
|
|
directives in free form and \f(CW\*(C`c$acc\*(C'\fR, \f(CW*$acc\fR and
|
||
|
|
\&\f(CW\*(C`!$acc\*(C'\fR directives in fixed form, \f(CW\*(C`!$\*(C'\fR conditional
|
||
|
|
compilation sentinels in free form and \f(CW\*(C`c$\*(C'\fR, \f(CW\*(C`*$\*(C'\fR and
|
||
|
|
\&\f(CW\*(C`!$\*(C'\fR sentinels in fixed form, and when linking arranges for the
|
||
|
|
OpenACC runtime library to be linked in.
|
||
|
|
.Sp
|
||
|
|
Note that this is an experimental feature, incomplete, and subject to
|
||
|
|
change in future versions of \s-1GCC. \s0 See
|
||
|
|
<\fBhttps://gcc.gnu.org/wiki/OpenACC\fR> for more information.
|
||
|
|
.IP "\fB\-fopenmp\fR" 4
|
||
|
|
.IX Item "-fopenmp"
|
||
|
|
Enable the OpenMP extensions. This includes OpenMP \f(CW\*(C`!$omp\*(C'\fR directives
|
||
|
|
in free form
|
||
|
|
and \f(CW\*(C`c$omp\*(C'\fR, \f(CW*$omp\fR and \f(CW\*(C`!$omp\*(C'\fR directives in fixed form,
|
||
|
|
\&\f(CW\*(C`!$\*(C'\fR conditional compilation sentinels in free form
|
||
|
|
and \f(CW\*(C`c$\*(C'\fR, \f(CW\*(C`*$\*(C'\fR and \f(CW\*(C`!$\*(C'\fR sentinels in fixed form,
|
||
|
|
and when linking arranges for the OpenMP runtime library to be linked
|
||
|
|
in. The option \fB\-fopenmp\fR implies \fB\-frecursive\fR.
|
||
|
|
.IP "\fB\-fno\-range\-check\fR" 4
|
||
|
|
.IX Item "-fno-range-check"
|
||
|
|
Disable range checking on results of simplification of constant
|
||
|
|
expressions during compilation. For example, \s-1GNU\s0 Fortran will give
|
||
|
|
an error at compile time when simplifying \f(CW\*(C`a = 1. / 0\*(C'\fR.
|
||
|
|
With this option, no error will be given and \f(CW\*(C`a\*(C'\fR will be assigned
|
||
|
|
the value \f(CW\*(C`+Infinity\*(C'\fR. If an expression evaluates to a value
|
||
|
|
outside of the relevant range of [\f(CW\*(C`\-HUGE()\*(C'\fR:\f(CW\*(C`HUGE()\*(C'\fR],
|
||
|
|
then the expression will be replaced by \f(CW\*(C`\-Inf\*(C'\fR or \f(CW\*(C`+Inf\*(C'\fR
|
||
|
|
as appropriate.
|
||
|
|
Similarly, \f(CW\*(C`DATA i/Z\*(AqFFFFFFFF\*(Aq/\*(C'\fR will result in an integer overflow
|
||
|
|
on most systems, but with \fB\-fno\-range\-check\fR the value will
|
||
|
|
\&\*(L"wrap around\*(R" and \f(CW\*(C`i\*(C'\fR will be initialized to \-1 instead.
|
||
|
|
.IP "\fB\-fdefault\-integer\-8\fR" 4
|
||
|
|
.IX Item "-fdefault-integer-8"
|
||
|
|
Set the default integer and logical types to an 8 byte wide type. This option
|
||
|
|
also affects the kind of integer constants like \f(CW42\fR. Unlike
|
||
|
|
\&\fB\-finteger\-4\-integer\-8\fR, it does not promote variables with explicit
|
||
|
|
kind declaration.
|
||
|
|
.IP "\fB\-fdefault\-real\-8\fR" 4
|
||
|
|
.IX Item "-fdefault-real-8"
|
||
|
|
Set the default real type to an 8 byte wide type. This option also affects
|
||
|
|
the kind of non-double real constants like \f(CW1.0\fR, and does promote
|
||
|
|
the default width of \f(CW\*(C`DOUBLE PRECISION\*(C'\fR to 16 bytes if possible, unless
|
||
|
|
\&\f(CW\*(C`\-fdefault\-double\-8\*(C'\fR is given, too. Unlike \fB\-freal\-4\-real\-8\fR,
|
||
|
|
it does not promote variables with explicit kind declaration.
|
||
|
|
.IP "\fB\-fdefault\-double\-8\fR" 4
|
||
|
|
.IX Item "-fdefault-double-8"
|
||
|
|
Set the \f(CW\*(C`DOUBLE PRECISION\*(C'\fR type to an 8 byte wide type. Do nothing if this
|
||
|
|
is already the default. If \fB\-fdefault\-real\-8\fR is given,
|
||
|
|
\&\f(CW\*(C`DOUBLE PRECISION\*(C'\fR would instead be promoted to 16 bytes if possible, and
|
||
|
|
\&\fB\-fdefault\-double\-8\fR can be used to prevent this. The kind of real
|
||
|
|
constants like \f(CW\*(C`1.d0\*(C'\fR will not be changed by \fB\-fdefault\-real\-8\fR
|
||
|
|
though, so also \fB\-fdefault\-double\-8\fR does not affect it.
|
||
|
|
.IP "\fB\-finteger\-4\-integer\-8\fR" 4
|
||
|
|
.IX Item "-finteger-4-integer-8"
|
||
|
|
Promote all \f(CW\*(C`INTEGER(KIND=4)\*(C'\fR entities to an \f(CW\*(C`INTEGER(KIND=8)\*(C'\fR
|
||
|
|
entities. If \f(CW\*(C`KIND=8\*(C'\fR is unavailable, then an error will be issued.
|
||
|
|
This option should be used with care and may not be suitable for your codes.
|
||
|
|
Areas of possible concern include calls to external procedures,
|
||
|
|
alignment in \f(CW\*(C`EQUIVALENCE\*(C'\fR and/or \f(CW\*(C`COMMON\*(C'\fR, generic interfaces,
|
||
|
|
\&\s-1BOZ\s0 literal constant conversion, and I/O. Inspection of the intermediate
|
||
|
|
representation of the translated Fortran code, produced by
|
||
|
|
\&\fB\-fdump\-tree\-original\fR, is suggested.
|
||
|
|
.IP "\fB\-freal\-4\-real\-8\fR" 4
|
||
|
|
.IX Item "-freal-4-real-8"
|
||
|
|
.PD 0
|
||
|
|
.IP "\fB\-freal\-4\-real\-10\fR" 4
|
||
|
|
.IX Item "-freal-4-real-10"
|
||
|
|
.IP "\fB\-freal\-4\-real\-16\fR" 4
|
||
|
|
.IX Item "-freal-4-real-16"
|
||
|
|
.IP "\fB\-freal\-8\-real\-4\fR" 4
|
||
|
|
.IX Item "-freal-8-real-4"
|
||
|
|
.IP "\fB\-freal\-8\-real\-10\fR" 4
|
||
|
|
.IX Item "-freal-8-real-10"
|
||
|
|
.IP "\fB\-freal\-8\-real\-16\fR" 4
|
||
|
|
.IX Item "-freal-8-real-16"
|
||
|
|
.PD
|
||
|
|
Promote all \f(CW\*(C`REAL(KIND=M)\*(C'\fR entities to \f(CW\*(C`REAL(KIND=N)\*(C'\fR entities.
|
||
|
|
If \f(CW\*(C`REAL(KIND=N)\*(C'\fR is unavailable, then an error will be issued.
|
||
|
|
All other real kind types are unaffected by this option.
|
||
|
|
These options should be used with care and may not be suitable for your
|
||
|
|
codes. Areas of possible concern include calls to external procedures,
|
||
|
|
alignment in \f(CW\*(C`EQUIVALENCE\*(C'\fR and/or \f(CW\*(C`COMMON\*(C'\fR, generic interfaces,
|
||
|
|
\&\s-1BOZ\s0 literal constant conversion, and I/O. Inspection of the intermediate
|
||
|
|
representation of the translated Fortran code, produced by
|
||
|
|
\&\fB\-fdump\-tree\-original\fR, is suggested.
|
||
|
|
.IP "\fB\-std=\fR\fIstd\fR" 4
|
||
|
|
.IX Item "-std=std"
|
||
|
|
Specify the standard to which the program is expected to conform, which
|
||
|
|
may be one of \fBf95\fR, \fBf2003\fR, \fBf2008\fR, \fBgnu\fR, or
|
||
|
|
\&\fBlegacy\fR. The default value for \fIstd\fR is \fBgnu\fR, which
|
||
|
|
specifies a superset of the Fortran 95 standard that includes all of the
|
||
|
|
extensions supported by \s-1GNU\s0 Fortran, although warnings will be given for
|
||
|
|
obsolete extensions not recommended for use in new code. The
|
||
|
|
\&\fBlegacy\fR value is equivalent but without the warnings for obsolete
|
||
|
|
extensions, and may be useful for old non-standard programs. The
|
||
|
|
\&\fBf95\fR, \fBf2003\fR and \fBf2008\fR values specify strict
|
||
|
|
conformance to the Fortran 95, Fortran 2003 and Fortran 2008 standards,
|
||
|
|
respectively; errors are given for all extensions beyond the relevant
|
||
|
|
language standard, and warnings are given for the Fortran 77 features
|
||
|
|
that are permitted but obsolescent in later standards. \fB\-std=f2008ts\fR
|
||
|
|
allows the Fortran 2008 standard including the additions of the
|
||
|
|
Technical Specification (\s-1TS\s0) 29113 on Further Interoperability of Fortran
|
||
|
|
with C and \s-1TS 18508\s0 on Additional Parallel Features in Fortran.
|
||
|
|
.SS "Enable and customize preprocessing"
|
||
|
|
.IX Subsection "Enable and customize preprocessing"
|
||
|
|
Preprocessor related options. See section
|
||
|
|
\&\fBPreprocessing and conditional compilation\fR for more detailed
|
||
|
|
information on preprocessing in \fBgfortran\fR.
|
||
|
|
.IP "\fB\-cpp\fR" 4
|
||
|
|
.IX Item "-cpp"
|
||
|
|
.PD 0
|
||
|
|
.IP "\fB\-nocpp\fR" 4
|
||
|
|
.IX Item "-nocpp"
|
||
|
|
.PD
|
||
|
|
Enable preprocessing. The preprocessor is automatically invoked if
|
||
|
|
the file extension is \fI.fpp\fR, \fI.FPP\fR, \fI.F\fR, \fI.FOR\fR,
|
||
|
|
\&\fI.FTN\fR, \fI.F90\fR, \fI.F95\fR, \fI.F03\fR or \fI.F08\fR. Use
|
||
|
|
this option to manually enable preprocessing of any kind of Fortran file.
|
||
|
|
.Sp
|
||
|
|
To disable preprocessing of files with any of the above listed extensions,
|
||
|
|
use the negative form: \fB\-nocpp\fR.
|
||
|
|
.Sp
|
||
|
|
The preprocessor is run in traditional mode. Any restrictions of the
|
||
|
|
file-format, especially the limits on line length, apply for
|
||
|
|
preprocessed output as well, so it might be advisable to use the
|
||
|
|
\&\fB\-ffree\-line\-length\-none\fR or \fB\-ffixed\-line\-length\-none\fR
|
||
|
|
options.
|
||
|
|
.IP "\fB\-dM\fR" 4
|
||
|
|
.IX Item "-dM"
|
||
|
|
Instead of the normal output, generate a list of \f(CW\*(Aq#define\*(Aq\fR
|
||
|
|
directives for all the macros defined during the execution of the
|
||
|
|
preprocessor, including predefined macros. This gives you a way
|
||
|
|
of finding out what is predefined in your version of the preprocessor.
|
||
|
|
Assuming you have no file \fIfoo.f90\fR, the command
|
||
|
|
.Sp
|
||
|
|
.Vb 1
|
||
|
|
\& touch foo.f90; gfortran \-cpp \-E \-dM foo.f90
|
||
|
|
.Ve
|
||
|
|
.Sp
|
||
|
|
will show all the predefined macros.
|
||
|
|
.IP "\fB\-dD\fR" 4
|
||
|
|
.IX Item "-dD"
|
||
|
|
Like \fB\-dM\fR except in two respects: it does not include the
|
||
|
|
predefined macros, and it outputs both the \f(CW\*(C`#define\*(C'\fR directives
|
||
|
|
and the result of preprocessing. Both kinds of output go to the
|
||
|
|
standard output file.
|
||
|
|
.IP "\fB\-dN\fR" 4
|
||
|
|
.IX Item "-dN"
|
||
|
|
Like \fB\-dD\fR, but emit only the macro names, not their expansions.
|
||
|
|
.IP "\fB\-dU\fR" 4
|
||
|
|
.IX Item "-dU"
|
||
|
|
Like \fBdD\fR except that only macros that are expanded, or whose
|
||
|
|
definedness is tested in preprocessor directives, are output; the
|
||
|
|
output is delayed until the use or test of the macro; and \f(CW\*(Aq#undef\*(Aq\fR
|
||
|
|
directives are also output for macros tested but undefined at the time.
|
||
|
|
.IP "\fB\-dI\fR" 4
|
||
|
|
.IX Item "-dI"
|
||
|
|
Output \f(CW\*(Aq#include\*(Aq\fR directives in addition to the result
|
||
|
|
of preprocessing.
|
||
|
|
.IP "\fB\-fworking\-directory\fR" 4
|
||
|
|
.IX Item "-fworking-directory"
|
||
|
|
Enable generation of linemarkers in the preprocessor output that will
|
||
|
|
let the compiler know the current working directory at the time of
|
||
|
|
preprocessing. When this option is enabled, the preprocessor will emit,
|
||
|
|
after the initial linemarker, a second linemarker with the current
|
||
|
|
working directory followed by two slashes. \s-1GCC\s0 will use this directory,
|
||
|
|
when it is present in the preprocessed input, as the directory emitted
|
||
|
|
as the current working directory in some debugging information formats.
|
||
|
|
This option is implicitly enabled if debugging information is enabled,
|
||
|
|
but this can be inhibited with the negated form
|
||
|
|
\&\fB\-fno\-working\-directory\fR. If the \fB\-P\fR flag is present
|
||
|
|
in the command line, this option has no effect, since no \f(CW\*(C`#line\*(C'\fR
|
||
|
|
directives are emitted whatsoever.
|
||
|
|
.IP "\fB\-idirafter\fR \fIdir\fR" 4
|
||
|
|
.IX Item "-idirafter dir"
|
||
|
|
Search \fIdir\fR for include files, but do it after all directories
|
||
|
|
specified with \fB\-I\fR and the standard system directories have
|
||
|
|
been exhausted. \fIdir\fR is treated as a system include directory.
|
||
|
|
If dir begins with \f(CW\*(C`=\*(C'\fR, then the \f(CW\*(C`=\*(C'\fR will be replaced by
|
||
|
|
the sysroot prefix; see \fB\-\-sysroot\fR and \fB\-isysroot\fR.
|
||
|
|
.IP "\fB\-imultilib\fR \fIdir\fR" 4
|
||
|
|
.IX Item "-imultilib dir"
|
||
|
|
Use \fIdir\fR as a subdirectory of the directory containing target-specific
|
||
|
|
\&\*(C+ headers.
|
||
|
|
.IP "\fB\-iprefix\fR \fIprefix\fR" 4
|
||
|
|
.IX Item "-iprefix prefix"
|
||
|
|
Specify \fIprefix\fR as the prefix for subsequent \fB\-iwithprefix\fR
|
||
|
|
options. If the \fIprefix\fR represents a directory, you should include
|
||
|
|
the final \f(CW\*(Aq/\*(Aq\fR.
|
||
|
|
.IP "\fB\-isysroot\fR \fIdir\fR" 4
|
||
|
|
.IX Item "-isysroot dir"
|
||
|
|
This option is like the \fB\-\-sysroot\fR option, but applies only to
|
||
|
|
header files. See the \fB\-\-sysroot\fR option for more information.
|
||
|
|
.IP "\fB\-iquote\fR \fIdir\fR" 4
|
||
|
|
.IX Item "-iquote dir"
|
||
|
|
Search \fIdir\fR only for header files requested with \f(CW\*(C`#include "file"\*(C'\fR;
|
||
|
|
they are not searched for \f(CW\*(C`#include <file>\*(C'\fR, before all directories
|
||
|
|
specified by \fB\-I\fR and before the standard system directories. If
|
||
|
|
\&\fIdir\fR begins with \f(CW\*(C`=\*(C'\fR, then the \f(CW\*(C`=\*(C'\fR will be replaced by the
|
||
|
|
sysroot prefix; see \fB\-\-sysroot\fR and \fB\-isysroot\fR.
|
||
|
|
.IP "\fB\-isystem\fR \fIdir\fR" 4
|
||
|
|
.IX Item "-isystem dir"
|
||
|
|
Search \fIdir\fR for header files, after all directories specified by
|
||
|
|
\&\fB\-I\fR but before the standard system directories. Mark it as a
|
||
|
|
system directory, so that it gets the same special treatment as is
|
||
|
|
applied to the standard system directories. If \fIdir\fR begins with
|
||
|
|
\&\f(CW\*(C`=\*(C'\fR, then the \f(CW\*(C`=\*(C'\fR will be replaced by the sysroot prefix;
|
||
|
|
see \fB\-\-sysroot\fR and \fB\-isysroot\fR.
|
||
|
|
.IP "\fB\-nostdinc\fR" 4
|
||
|
|
.IX Item "-nostdinc"
|
||
|
|
Do not search the standard system directories for header files. Only
|
||
|
|
the directories you have specified with \fB\-I\fR options (and the
|
||
|
|
directory of the current file, if appropriate) are searched.
|
||
|
|
.IP "\fB\-undef\fR" 4
|
||
|
|
.IX Item "-undef"
|
||
|
|
Do not predefine any system-specific or GCC-specific macros.
|
||
|
|
The standard predefined macros remain defined.
|
||
|
|
.IP "\fB\-A\fR\fIpredicate\fR\fB=\fR\fIanswer\fR" 4
|
||
|
|
.IX Item "-Apredicate=answer"
|
||
|
|
Make an assertion with the predicate \fIpredicate\fR and answer \fIanswer\fR.
|
||
|
|
This form is preferred to the older form \-A predicate(answer), which is still
|
||
|
|
supported, because it does not use shell special characters.
|
||
|
|
.IP "\fB\-A\-\fR\fIpredicate\fR\fB=\fR\fIanswer\fR" 4
|
||
|
|
.IX Item "-A-predicate=answer"
|
||
|
|
Cancel an assertion with the predicate \fIpredicate\fR and answer \fIanswer\fR.
|
||
|
|
.IP "\fB\-C\fR" 4
|
||
|
|
.IX Item "-C"
|
||
|
|
Do not discard comments. All comments are passed through to the output
|
||
|
|
file, except for comments in processed directives, which are deleted
|
||
|
|
along with the directive.
|
||
|
|
.Sp
|
||
|
|
You should be prepared for side effects when using \fB\-C\fR; it causes
|
||
|
|
the preprocessor to treat comments as tokens in their own right. For example,
|
||
|
|
comments appearing at the start of what would be a directive line have the
|
||
|
|
effect of turning that line into an ordinary source line, since the first
|
||
|
|
token on the line is no longer a \f(CW\*(Aq#\*(Aq\fR.
|
||
|
|
.Sp
|
||
|
|
Warning: this currently handles C\-Style comments only. The preprocessor
|
||
|
|
does not yet recognize Fortran-style comments.
|
||
|
|
.IP "\fB\-CC\fR" 4
|
||
|
|
.IX Item "-CC"
|
||
|
|
Do not discard comments, including during macro expansion. This is like
|
||
|
|
\&\fB\-C\fR, except that comments contained within macros are also passed
|
||
|
|
through to the output file where the macro is expanded.
|
||
|
|
.Sp
|
||
|
|
In addition to the side-effects of the \fB\-C\fR option, the \fB\-CC\fR
|
||
|
|
option causes all \*(C+\-style comments inside a macro to be converted to C\-style
|
||
|
|
comments. This is to prevent later use of that macro from inadvertently
|
||
|
|
commenting out the remainder of the source line. The \fB\-CC\fR option
|
||
|
|
is generally used to support lint comments.
|
||
|
|
.Sp
|
||
|
|
Warning: this currently handles C\- and \*(C+\-Style comments only. The
|
||
|
|
preprocessor does not yet recognize Fortran-style comments.
|
||
|
|
.IP "\fB\-D\fR\fIname\fR" 4
|
||
|
|
.IX Item "-Dname"
|
||
|
|
Predefine name as a macro, with definition \f(CW1\fR.
|
||
|
|
.IP "\fB\-D\fR\fIname\fR\fB=\fR\fIdefinition\fR" 4
|
||
|
|
.IX Item "-Dname=definition"
|
||
|
|
The contents of \fIdefinition\fR are tokenized and processed as if they
|
||
|
|
appeared during translation phase three in a \f(CW\*(Aq#define\*(Aq\fR directive.
|
||
|
|
In particular, the definition will be truncated by embedded newline
|
||
|
|
characters.
|
||
|
|
.Sp
|
||
|
|
If you are invoking the preprocessor from a shell or shell-like program
|
||
|
|
you may need to use the shell's quoting syntax to protect characters such
|
||
|
|
as spaces that have a meaning in the shell syntax.
|
||
|
|
.Sp
|
||
|
|
If you wish to define a function-like macro on the command line, write
|
||
|
|
its argument list with surrounding parentheses before the equals sign
|
||
|
|
(if any). Parentheses are meaningful to most shells, so you will need
|
||
|
|
to quote the option. With sh and csh, \f(CW\*(C`\-D\*(Aqname(args...)=definition\*(Aq\*(C'\fR
|
||
|
|
works.
|
||
|
|
.Sp
|
||
|
|
\&\fB\-D\fR and \fB\-U\fR options are processed in the order they are
|
||
|
|
given on the command line. All \-imacros file and \-include file options
|
||
|
|
are processed after all \-D and \-U options.
|
||
|
|
.IP "\fB\-H\fR" 4
|
||
|
|
.IX Item "-H"
|
||
|
|
Print the name of each header file used, in addition to other normal
|
||
|
|
activities. Each name is indented to show how deep in the \f(CW\*(Aq#include\*(Aq\fR
|
||
|
|
stack it is.
|
||
|
|
.IP "\fB\-P\fR" 4
|
||
|
|
.IX Item "-P"
|
||
|
|
Inhibit generation of linemarkers in the output from the preprocessor.
|
||
|
|
This might be useful when running the preprocessor on something that
|
||
|
|
is not C code, and will be sent to a program which might be confused
|
||
|
|
by the linemarkers.
|
||
|
|
.IP "\fB\-U\fR\fIname\fR" 4
|
||
|
|
.IX Item "-Uname"
|
||
|
|
Cancel any previous definition of \fIname\fR, either built in or provided
|
||
|
|
with a \fB\-D\fR option.
|
||
|
|
.SS "Options to request or suppress errors and warnings"
|
||
|
|
.IX Subsection "Options to request or suppress errors and warnings"
|
||
|
|
Errors are diagnostic messages that report that the \s-1GNU\s0 Fortran compiler
|
||
|
|
cannot compile the relevant piece of source code. The compiler will
|
||
|
|
continue to process the program in an attempt to report further errors
|
||
|
|
to aid in debugging, but will not produce any compiled output.
|
||
|
|
.PP
|
||
|
|
Warnings are diagnostic messages that report constructions which
|
||
|
|
are not inherently erroneous but which are risky or suggest there is
|
||
|
|
likely to be a bug in the program. Unless \fB\-Werror\fR is specified,
|
||
|
|
they do not prevent compilation of the program.
|
||
|
|
.PP
|
||
|
|
You can request many specific warnings with options beginning \fB\-W\fR,
|
||
|
|
for example \fB\-Wimplicit\fR to request warnings on implicit
|
||
|
|
declarations. Each of these specific warning options also has a
|
||
|
|
negative form beginning \fB\-Wno\-\fR to turn off warnings;
|
||
|
|
for example, \fB\-Wno\-implicit\fR. This manual lists only one of the
|
||
|
|
two forms, whichever is not the default.
|
||
|
|
.PP
|
||
|
|
These options control the amount and kinds of errors and warnings produced
|
||
|
|
by \s-1GNU\s0 Fortran:
|
||
|
|
.IP "\fB\-fmax\-errors=\fR\fIn\fR" 4
|
||
|
|
.IX Item "-fmax-errors=n"
|
||
|
|
Limits the maximum number of error messages to \fIn\fR, at which point
|
||
|
|
\&\s-1GNU\s0 Fortran bails out rather than attempting to continue processing the
|
||
|
|
source code. If \fIn\fR is 0, there is no limit on the number of error
|
||
|
|
messages produced.
|
||
|
|
.IP "\fB\-fsyntax\-only\fR" 4
|
||
|
|
.IX Item "-fsyntax-only"
|
||
|
|
Check the code for syntax errors, but do not actually compile it. This
|
||
|
|
will generate module files for each module present in the code, but no
|
||
|
|
other output file.
|
||
|
|
.IP "\fB\-pedantic\fR" 4
|
||
|
|
.IX Item "-pedantic"
|
||
|
|
Issue warnings for uses of extensions to Fortran 95.
|
||
|
|
\&\fB\-pedantic\fR also applies to C\-language constructs where they
|
||
|
|
occur in \s-1GNU\s0 Fortran source files, such as use of \fB\ee\fR in a
|
||
|
|
character constant within a directive like \f(CW\*(C`#include\*(C'\fR.
|
||
|
|
.Sp
|
||
|
|
Valid Fortran 95 programs should compile properly with or without
|
||
|
|
this option.
|
||
|
|
However, without this option, certain \s-1GNU\s0 extensions and traditional
|
||
|
|
Fortran features are supported as well.
|
||
|
|
With this option, many of them are rejected.
|
||
|
|
.Sp
|
||
|
|
Some users try to use \fB\-pedantic\fR to check programs for conformance.
|
||
|
|
They soon find that it does not do quite what they want\-\-\-it finds some
|
||
|
|
nonstandard practices, but not all.
|
||
|
|
However, improvements to \s-1GNU\s0 Fortran in this area are welcome.
|
||
|
|
.Sp
|
||
|
|
This should be used in conjunction with \fB\-std=f95\fR,
|
||
|
|
\&\fB\-std=f2003\fR or \fB\-std=f2008\fR.
|
||
|
|
.IP "\fB\-pedantic\-errors\fR" 4
|
||
|
|
.IX Item "-pedantic-errors"
|
||
|
|
Like \fB\-pedantic\fR, except that errors are produced rather than
|
||
|
|
warnings.
|
||
|
|
.IP "\fB\-Wall\fR" 4
|
||
|
|
.IX Item "-Wall"
|
||
|
|
Enables commonly used warning options pertaining to usage that
|
||
|
|
we recommend avoiding and that we believe are easy to avoid.
|
||
|
|
This currently includes \fB\-Waliasing\fR, \fB\-Wampersand\fR,
|
||
|
|
\&\fB\-Wconversion\fR, \fB\-Wsurprising\fR, \fB\-Wc\-binding\-type\fR,
|
||
|
|
\&\fB\-Wintrinsics\-std\fR, \fB\-Wtabs\fR, \fB\-Wintrinsic\-shadow\fR,
|
||
|
|
\&\fB\-Wline\-truncation\fR, \fB\-Wtarget\-lifetime\fR,
|
||
|
|
\&\fB\-Winteger\-division\fR, \fB\-Wreal\-q\-constant\fR and \fB\-Wunused\fR.
|
||
|
|
.IP "\fB\-Waliasing\fR" 4
|
||
|
|
.IX Item "-Waliasing"
|
||
|
|
Warn about possible aliasing of dummy arguments. Specifically, it warns
|
||
|
|
if the same actual argument is associated with a dummy argument with
|
||
|
|
\&\f(CW\*(C`INTENT(IN)\*(C'\fR and a dummy argument with \f(CW\*(C`INTENT(OUT)\*(C'\fR in a call
|
||
|
|
with an explicit interface.
|
||
|
|
.Sp
|
||
|
|
The following example will trigger the warning.
|
||
|
|
.Sp
|
||
|
|
.Vb 7
|
||
|
|
\& interface
|
||
|
|
\& subroutine bar(a,b)
|
||
|
|
\& integer, intent(in) :: a
|
||
|
|
\& integer, intent(out) :: b
|
||
|
|
\& end subroutine
|
||
|
|
\& end interface
|
||
|
|
\& integer :: a
|
||
|
|
\&
|
||
|
|
\& call bar(a,a)
|
||
|
|
.Ve
|
||
|
|
.IP "\fB\-Wampersand\fR" 4
|
||
|
|
.IX Item "-Wampersand"
|
||
|
|
Warn about missing ampersand in continued character constants. The warning is
|
||
|
|
given with \fB\-Wampersand\fR, \fB\-pedantic\fR, \fB\-std=f95\fR,
|
||
|
|
\&\fB\-std=f2003\fR and \fB\-std=f2008\fR. Note: With no ampersand
|
||
|
|
given in a continued character constant, \s-1GNU\s0 Fortran assumes continuation
|
||
|
|
at the first non-comment, non-whitespace character after the ampersand
|
||
|
|
that initiated the continuation.
|
||
|
|
.IP "\fB\-Warray\-temporaries\fR" 4
|
||
|
|
.IX Item "-Warray-temporaries"
|
||
|
|
Warn about array temporaries generated by the compiler. The information
|
||
|
|
generated by this warning is sometimes useful in optimization, in order to
|
||
|
|
avoid such temporaries.
|
||
|
|
.IP "\fB\-Wc\-binding\-type\fR" 4
|
||
|
|
.IX Item "-Wc-binding-type"
|
||
|
|
Warn if the a variable might not be C interoperable. In particular, warn if
|
||
|
|
the variable has been declared using an intrinsic type with default kind
|
||
|
|
instead of using a kind parameter defined for C interoperability in the
|
||
|
|
intrinsic \f(CW\*(C`ISO_C_Binding\*(C'\fR module. This option is implied by
|
||
|
|
\&\fB\-Wall\fR.
|
||
|
|
.IP "\fB\-Wcharacter\-truncation\fR" 4
|
||
|
|
.IX Item "-Wcharacter-truncation"
|
||
|
|
Warn when a character assignment will truncate the assigned string.
|
||
|
|
.IP "\fB\-Wline\-truncation\fR" 4
|
||
|
|
.IX Item "-Wline-truncation"
|
||
|
|
Warn when a source code line will be truncated. This option is
|
||
|
|
implied by \fB\-Wall\fR. For free-form source code, the default is
|
||
|
|
\&\fB\-Werror=line\-truncation\fR such that truncations are reported as
|
||
|
|
error.
|
||
|
|
.IP "\fB\-Wconversion\fR" 4
|
||
|
|
.IX Item "-Wconversion"
|
||
|
|
Warn about implicit conversions that are likely to change the value of
|
||
|
|
the expression after conversion. Implied by \fB\-Wall\fR.
|
||
|
|
.IP "\fB\-Wconversion\-extra\fR" 4
|
||
|
|
.IX Item "-Wconversion-extra"
|
||
|
|
Warn about implicit conversions between different types and kinds. This
|
||
|
|
option does \fInot\fR imply \fB\-Wconversion\fR.
|
||
|
|
.IP "\fB\-Wextra\fR" 4
|
||
|
|
.IX Item "-Wextra"
|
||
|
|
Enables some warning options for usages of language features which
|
||
|
|
may be problematic. This currently includes \fB\-Wcompare\-reals\fR
|
||
|
|
and \fB\-Wunused\-parameter\fR.
|
||
|
|
.IP "\fB\-Wimplicit\-interface\fR" 4
|
||
|
|
.IX Item "-Wimplicit-interface"
|
||
|
|
Warn if a procedure is called without an explicit interface.
|
||
|
|
Note this only checks that an explicit interface is present. It does not
|
||
|
|
check that the declared interfaces are consistent across program units.
|
||
|
|
.IP "\fB\-Wimplicit\-procedure\fR" 4
|
||
|
|
.IX Item "-Wimplicit-procedure"
|
||
|
|
Warn if a procedure is called that has neither an explicit interface
|
||
|
|
nor has been declared as \f(CW\*(C`EXTERNAL\*(C'\fR.
|
||
|
|
.IP "\fB\-Winteger\-division\fR" 4
|
||
|
|
.IX Item "-Winteger-division"
|
||
|
|
Warn if a constant integer division truncates it result.
|
||
|
|
As an example, 3/5 evaluates to 0.
|
||
|
|
.IP "\fB\-Wintrinsics\-std\fR" 4
|
||
|
|
.IX Item "-Wintrinsics-std"
|
||
|
|
Warn if \fBgfortran\fR finds a procedure named like an intrinsic not
|
||
|
|
available in the currently selected standard (with \fB\-std\fR) and treats
|
||
|
|
it as \f(CW\*(C`EXTERNAL\*(C'\fR procedure because of this. \fB\-fall\-intrinsics\fR can
|
||
|
|
be used to never trigger this behavior and always link to the intrinsic
|
||
|
|
regardless of the selected standard.
|
||
|
|
.IP "\fB\-Wreal\-q\-constant\fR" 4
|
||
|
|
.IX Item "-Wreal-q-constant"
|
||
|
|
Produce a warning if a real-literal-constant contains a \f(CW\*(C`q\*(C'\fR
|
||
|
|
exponent-letter.
|
||
|
|
.IP "\fB\-Wsurprising\fR" 4
|
||
|
|
.IX Item "-Wsurprising"
|
||
|
|
Produce a warning when \*(L"suspicious\*(R" code constructs are encountered.
|
||
|
|
While technically legal these usually indicate that an error has been made.
|
||
|
|
.Sp
|
||
|
|
This currently produces a warning under the following circumstances:
|
||
|
|
.RS 4
|
||
|
|
.IP "*" 4
|
||
|
|
An \s-1INTEGER SELECT\s0 construct has a \s-1CASE\s0 that can never be matched as its
|
||
|
|
lower value is greater than its upper value.
|
||
|
|
.IP "*" 4
|
||
|
|
A \s-1LOGICAL SELECT\s0 construct has three \s-1CASE\s0 statements.
|
||
|
|
.IP "*" 4
|
||
|
|
A \s-1TRANSFER\s0 specifies a source that is shorter than the destination.
|
||
|
|
.IP "*" 4
|
||
|
|
The type of a function result is declared more than once with the same type. If
|
||
|
|
\&\fB\-pedantic\fR or standard-conforming mode is enabled, this is an error.
|
||
|
|
.IP "*" 4
|
||
|
|
A \f(CW\*(C`CHARACTER\*(C'\fR variable is declared with negative length.
|
||
|
|
.RE
|
||
|
|
.RS 4
|
||
|
|
.RE
|
||
|
|
.IP "\fB\-Wtabs\fR" 4
|
||
|
|
.IX Item "-Wtabs"
|
||
|
|
By default, tabs are accepted as whitespace, but tabs are not members
|
||
|
|
of the Fortran Character Set. For continuation lines, a tab followed
|
||
|
|
by a digit between 1 and 9 is supported. \fB\-Wtabs\fR will cause
|
||
|
|
a warning to be issued if a tab is encountered. Note, \fB\-Wtabs\fR
|
||
|
|
is active for \fB\-pedantic\fR, \fB\-std=f95\fR, \fB\-std=f2003\fR,
|
||
|
|
\&\fB\-std=f2008\fR, \fB\-std=f2008ts\fR and \fB\-Wall\fR.
|
||
|
|
.IP "\fB\-Wunderflow\fR" 4
|
||
|
|
.IX Item "-Wunderflow"
|
||
|
|
Produce a warning when numerical constant expressions are
|
||
|
|
encountered, which yield an \s-1UNDERFLOW\s0 during compilation. Enabled by default.
|
||
|
|
.IP "\fB\-Wintrinsic\-shadow\fR" 4
|
||
|
|
.IX Item "-Wintrinsic-shadow"
|
||
|
|
Warn if a user-defined procedure or module procedure has the same name as an
|
||
|
|
intrinsic; in this case, an explicit interface or \f(CW\*(C`EXTERNAL\*(C'\fR or
|
||
|
|
\&\f(CW\*(C`INTRINSIC\*(C'\fR declaration might be needed to get calls later resolved to
|
||
|
|
the desired intrinsic/procedure. This option is implied by \fB\-Wall\fR.
|
||
|
|
.IP "\fB\-Wuse\-without\-only\fR" 4
|
||
|
|
.IX Item "-Wuse-without-only"
|
||
|
|
Warn if a \f(CW\*(C`USE\*(C'\fR statement has no \f(CW\*(C`ONLY\*(C'\fR qualifier and
|
||
|
|
thus implicitly imports all public entities of the used module.
|
||
|
|
.IP "\fB\-Wunused\-dummy\-argument\fR" 4
|
||
|
|
.IX Item "-Wunused-dummy-argument"
|
||
|
|
Warn about unused dummy arguments. This option is implied by \fB\-Wall\fR.
|
||
|
|
.IP "\fB\-Wunused\-parameter\fR" 4
|
||
|
|
.IX Item "-Wunused-parameter"
|
||
|
|
Contrary to \fBgcc\fR's meaning of \fB\-Wunused\-parameter\fR,
|
||
|
|
\&\fBgfortran\fR's implementation of this option does not warn
|
||
|
|
about unused dummy arguments (see \fB\-Wunused\-dummy\-argument\fR),
|
||
|
|
but about unused \f(CW\*(C`PARAMETER\*(C'\fR values. \fB\-Wunused\-parameter\fR
|
||
|
|
is implied by \fB\-Wextra\fR if also \fB\-Wunused\fR or
|
||
|
|
\&\fB\-Wall\fR is used.
|
||
|
|
.IP "\fB\-Walign\-commons\fR" 4
|
||
|
|
.IX Item "-Walign-commons"
|
||
|
|
By default, \fBgfortran\fR warns about any occasion of variables being
|
||
|
|
padded for proper alignment inside a \f(CW\*(C`COMMON\*(C'\fR block. This warning can be turned
|
||
|
|
off via \fB\-Wno\-align\-commons\fR. See also \fB\-falign\-commons\fR.
|
||
|
|
.IP "\fB\-Wfunction\-elimination\fR" 4
|
||
|
|
.IX Item "-Wfunction-elimination"
|
||
|
|
Warn if any calls to functions are eliminated by the optimizations
|
||
|
|
enabled by the \fB\-ffrontend\-optimize\fR option.
|
||
|
|
.IP "\fB\-Wrealloc\-lhs\fR" 4
|
||
|
|
.IX Item "-Wrealloc-lhs"
|
||
|
|
Warn when the compiler might insert code to for allocation or reallocation of
|
||
|
|
an allocatable array variable of intrinsic type in intrinsic assignments. In
|
||
|
|
hot loops, the Fortran 2003 reallocation feature may reduce the performance.
|
||
|
|
If the array is already allocated with the correct shape, consider using a
|
||
|
|
whole-array array-spec (e.g. \f(CW\*(C`(:,:,:)\*(C'\fR) for the variable on the left-hand
|
||
|
|
side to prevent the reallocation check. Note that in some cases the warning
|
||
|
|
is shown, even if the compiler will optimize reallocation checks away. For
|
||
|
|
instance, when the right-hand side contains the same variable multiplied by
|
||
|
|
a scalar. See also \fB\-frealloc\-lhs\fR.
|
||
|
|
.IP "\fB\-Wrealloc\-lhs\-all\fR" 4
|
||
|
|
.IX Item "-Wrealloc-lhs-all"
|
||
|
|
Warn when the compiler inserts code to for allocation or reallocation of an
|
||
|
|
allocatable variable; this includes scalars and derived types.
|
||
|
|
.IP "\fB\-Wcompare\-reals\fR" 4
|
||
|
|
.IX Item "-Wcompare-reals"
|
||
|
|
Warn when comparing real or complex types for equality or inequality.
|
||
|
|
This option is implied by \fB\-Wextra\fR.
|
||
|
|
.IP "\fB\-Wtarget\-lifetime\fR" 4
|
||
|
|
.IX Item "-Wtarget-lifetime"
|
||
|
|
Warn if the pointer in a pointer assignment might be longer than the its
|
||
|
|
target. This option is implied by \fB\-Wall\fR.
|
||
|
|
.IP "\fB\-Wzerotrip\fR" 4
|
||
|
|
.IX Item "-Wzerotrip"
|
||
|
|
Warn if a \f(CW\*(C`DO\*(C'\fR loop is known to execute zero times at compile
|
||
|
|
time. This option is implied by \fB\-Wall\fR.
|
||
|
|
.IP "\fB\-Werror\fR" 4
|
||
|
|
.IX Item "-Werror"
|
||
|
|
Turns all warnings into errors.
|
||
|
|
.PP
|
||
|
|
Some of these have no effect when compiling programs written in Fortran.
|
||
|
|
.SS "Options for debugging your program or \s-1GNU\s0 Fortran"
|
||
|
|
.IX Subsection "Options for debugging your program or GNU Fortran"
|
||
|
|
\&\s-1GNU\s0 Fortran has various special options that are used for debugging
|
||
|
|
either your program or the \s-1GNU\s0 Fortran compiler.
|
||
|
|
.IP "\fB\-fdump\-fortran\-original\fR" 4
|
||
|
|
.IX Item "-fdump-fortran-original"
|
||
|
|
Output the internal parse tree after translating the source program
|
||
|
|
into internal representation. Only really useful for debugging the
|
||
|
|
\&\s-1GNU\s0 Fortran compiler itself.
|
||
|
|
.IP "\fB\-fdump\-fortran\-optimized\fR" 4
|
||
|
|
.IX Item "-fdump-fortran-optimized"
|
||
|
|
Output the parse tree after front-end optimization. Only really
|
||
|
|
useful for debugging the \s-1GNU\s0 Fortran compiler itself.
|
||
|
|
.IP "\fB\-fdump\-parse\-tree\fR" 4
|
||
|
|
.IX Item "-fdump-parse-tree"
|
||
|
|
Output the internal parse tree after translating the source program
|
||
|
|
into internal representation. Only really useful for debugging the
|
||
|
|
\&\s-1GNU\s0 Fortran compiler itself. This option is deprecated; use
|
||
|
|
\&\f(CW\*(C`\-fdump\-fortran\-original\*(C'\fR instead.
|
||
|
|
.IP "\fB\-ffpe\-trap=\fR\fIlist\fR" 4
|
||
|
|
.IX Item "-ffpe-trap=list"
|
||
|
|
Specify a list of floating point exception traps to enable. On most
|
||
|
|
systems, if a floating point exception occurs and the trap for that
|
||
|
|
exception is enabled, a \s-1SIGFPE\s0 signal will be sent and the program
|
||
|
|
being aborted, producing a core file useful for debugging. \fIlist\fR
|
||
|
|
is a (possibly empty) comma-separated list of the following
|
||
|
|
exceptions: \fBinvalid\fR (invalid floating point operation, such as
|
||
|
|
\&\f(CW\*(C`SQRT(\-1.0)\*(C'\fR), \fBzero\fR (division by zero), \fBoverflow\fR
|
||
|
|
(overflow in a floating point operation), \fBunderflow\fR (underflow
|
||
|
|
in a floating point operation), \fBinexact\fR (loss of precision
|
||
|
|
during operation), and \fBdenormal\fR (operation performed on a
|
||
|
|
denormal value). The first five exceptions correspond to the five
|
||
|
|
\&\s-1IEEE 754\s0 exceptions, whereas the last one (\fBdenormal\fR) is not
|
||
|
|
part of the \s-1IEEE 754\s0 standard but is available on some common
|
||
|
|
architectures such as x86.
|
||
|
|
.Sp
|
||
|
|
The first three exceptions (\fBinvalid\fR, \fBzero\fR, and
|
||
|
|
\&\fBoverflow\fR) often indicate serious errors, and unless the program
|
||
|
|
has provisions for dealing with these exceptions, enabling traps for
|
||
|
|
these three exceptions is probably a good idea.
|
||
|
|
.Sp
|
||
|
|
Many, if not most, floating point operations incur loss of precision
|
||
|
|
due to rounding, and hence the \f(CW\*(C`ffpe\-trap=inexact\*(C'\fR is likely to
|
||
|
|
be uninteresting in practice.
|
||
|
|
.Sp
|
||
|
|
By default no exception traps are enabled.
|
||
|
|
.IP "\fB\-ffpe\-summary=\fR\fIlist\fR" 4
|
||
|
|
.IX Item "-ffpe-summary=list"
|
||
|
|
Specify a list of floating-point exceptions, whose flag status is printed
|
||
|
|
to \f(CW\*(C`ERROR_UNIT\*(C'\fR when invoking \f(CW\*(C`STOP\*(C'\fR and \f(CW\*(C`ERROR STOP\*(C'\fR.
|
||
|
|
\&\fIlist\fR can be either \fBnone\fR, \fBall\fR or a comma-separated list
|
||
|
|
of the following exceptions: \fBinvalid\fR, \fBzero\fR, \fBoverflow\fR,
|
||
|
|
\&\fBunderflow\fR, \fBinexact\fR and \fBdenormal\fR. (See
|
||
|
|
\&\fB\-ffpe\-trap\fR for a description of the exceptions.)
|
||
|
|
.Sp
|
||
|
|
By default, a summary for all exceptions but \fBinexact\fR is shown.
|
||
|
|
.IP "\fB\-fno\-backtrace\fR" 4
|
||
|
|
.IX Item "-fno-backtrace"
|
||
|
|
When a serious runtime error is encountered or a deadly signal is
|
||
|
|
emitted (segmentation fault, illegal instruction, bus error,
|
||
|
|
floating-point exception, and the other \s-1POSIX\s0 signals that have the
|
||
|
|
action \fBcore\fR), the Fortran runtime library tries to output a
|
||
|
|
backtrace of the error. \f(CW\*(C`\-fno\-backtrace\*(C'\fR disables the backtrace
|
||
|
|
generation. This option only has influence for compilation of the
|
||
|
|
Fortran main program.
|
||
|
|
.SS "Options for directory search"
|
||
|
|
.IX Subsection "Options for directory search"
|
||
|
|
These options affect how \s-1GNU\s0 Fortran searches
|
||
|
|
for files specified by the \f(CW\*(C`INCLUDE\*(C'\fR directive and where it searches
|
||
|
|
for previously compiled modules.
|
||
|
|
.PP
|
||
|
|
It also affects the search paths used by \fBcpp\fR when used to preprocess
|
||
|
|
Fortran source.
|
||
|
|
.IP "\fB\-I\fR\fIdir\fR" 4
|
||
|
|
.IX Item "-Idir"
|
||
|
|
These affect interpretation of the \f(CW\*(C`INCLUDE\*(C'\fR directive
|
||
|
|
(as well as of the \f(CW\*(C`#include\*(C'\fR directive of the \fBcpp\fR
|
||
|
|
preprocessor).
|
||
|
|
.Sp
|
||
|
|
Also note that the general behavior of \fB\-I\fR and
|
||
|
|
\&\f(CW\*(C`INCLUDE\*(C'\fR is pretty much the same as of \fB\-I\fR with
|
||
|
|
\&\f(CW\*(C`#include\*(C'\fR in the \fBcpp\fR preprocessor, with regard to
|
||
|
|
looking for \fIheader.gcc\fR files and other such things.
|
||
|
|
.Sp
|
||
|
|
This path is also used to search for \fI.mod\fR files when previously
|
||
|
|
compiled modules are required by a \f(CW\*(C`USE\*(C'\fR statement.
|
||
|
|
.IP "\fB\-J\fR\fIdir\fR" 4
|
||
|
|
.IX Item "-Jdir"
|
||
|
|
This option specifies where to put \fI.mod\fR files for compiled modules.
|
||
|
|
It is also added to the list of directories to searched by an \f(CW\*(C`USE\*(C'\fR
|
||
|
|
statement.
|
||
|
|
.Sp
|
||
|
|
The default is the current directory.
|
||
|
|
.IP "\fB\-fintrinsic\-modules\-path\fR \fIdir\fR" 4
|
||
|
|
.IX Item "-fintrinsic-modules-path dir"
|
||
|
|
This option specifies the location of pre-compiled intrinsic modules, if
|
||
|
|
they are not in the default location expected by the compiler.
|
||
|
|
.SS "Influencing the linking step"
|
||
|
|
.IX Subsection "Influencing the linking step"
|
||
|
|
These options come into play when the compiler links object files into an
|
||
|
|
executable output file. They are meaningless if the compiler is not doing
|
||
|
|
a link step.
|
||
|
|
.IP "\fB\-static\-libgfortran\fR" 4
|
||
|
|
.IX Item "-static-libgfortran"
|
||
|
|
On systems that provide \fIlibgfortran\fR as a shared and a static
|
||
|
|
library, this option forces the use of the static version. If no
|
||
|
|
shared version of \fIlibgfortran\fR was built when the compiler was
|
||
|
|
configured, this option has no effect.
|
||
|
|
.SS "Influencing runtime behavior"
|
||
|
|
.IX Subsection "Influencing runtime behavior"
|
||
|
|
These options affect the runtime behavior of programs compiled with \s-1GNU\s0 Fortran.
|
||
|
|
.IP "\fB\-fconvert=\fR\fIconversion\fR" 4
|
||
|
|
.IX Item "-fconvert=conversion"
|
||
|
|
Specify the representation of data for unformatted files. Valid
|
||
|
|
values for conversion are: \fBnative\fR, the default; \fBswap\fR,
|
||
|
|
swap between big\- and little-endian; \fBbig-endian\fR, use big-endian
|
||
|
|
representation for unformatted files; \fBlittle-endian\fR, use little-endian
|
||
|
|
representation for unformatted files.
|
||
|
|
.Sp
|
||
|
|
\&\fIThis option has an effect only when used in the main program.
|
||
|
|
The \f(CI\*(C`CONVERT\*(C'\fI specifier and the \s-1GFORTRAN_CONVERT_UNIT\s0 environment
|
||
|
|
variable override the default specified by \f(BI\-fconvert\fI.\fR
|
||
|
|
.IP "\fB\-frecord\-marker=\fR\fIlength\fR" 4
|
||
|
|
.IX Item "-frecord-marker=length"
|
||
|
|
Specify the length of record markers for unformatted files.
|
||
|
|
Valid values for \fIlength\fR are 4 and 8. Default is 4.
|
||
|
|
\&\fIThis is different from previous versions of\fR \fBgfortran\fR,
|
||
|
|
which specified a default record marker length of 8 on most
|
||
|
|
systems. If you want to read or write files compatible
|
||
|
|
with earlier versions of \fBgfortran\fR, use \fB\-frecord\-marker=8\fR.
|
||
|
|
.IP "\fB\-fmax\-subrecord\-length=\fR\fIlength\fR" 4
|
||
|
|
.IX Item "-fmax-subrecord-length=length"
|
||
|
|
Specify the maximum length for a subrecord. The maximum permitted
|
||
|
|
value for length is 2147483639, which is also the default. Only
|
||
|
|
really useful for use by the gfortran testsuite.
|
||
|
|
.IP "\fB\-fsign\-zero\fR" 4
|
||
|
|
.IX Item "-fsign-zero"
|
||
|
|
When enabled, floating point numbers of value zero with the sign bit set
|
||
|
|
are written as negative number in formatted output and treated as
|
||
|
|
negative in the \f(CW\*(C`SIGN\*(C'\fR intrinsic. \fB\-fno\-sign\-zero\fR does not
|
||
|
|
print the negative sign of zero values (or values rounded to zero for I/O)
|
||
|
|
and regards zero as positive number in the \f(CW\*(C`SIGN\*(C'\fR intrinsic for
|
||
|
|
compatibility with Fortran 77. The default is \fB\-fsign\-zero\fR.
|
||
|
|
.SS "Options for code generation conventions"
|
||
|
|
.IX Subsection "Options for code generation conventions"
|
||
|
|
These machine-independent options control the interface conventions
|
||
|
|
used in code generation.
|
||
|
|
.PP
|
||
|
|
Most of them have both positive and negative forms; the negative form
|
||
|
|
of \fB\-ffoo\fR would be \fB\-fno\-foo\fR. In the table below, only
|
||
|
|
one of the forms is listed\-\-\-the one which is not the default. You
|
||
|
|
can figure out the other form by either removing \fBno\-\fR or adding
|
||
|
|
it.
|
||
|
|
.IP "\fB\-fno\-automatic\fR" 4
|
||
|
|
.IX Item "-fno-automatic"
|
||
|
|
Treat each program unit (except those marked as \s-1RECURSIVE\s0) as if the
|
||
|
|
\&\f(CW\*(C`SAVE\*(C'\fR statement were specified for every local variable and array
|
||
|
|
referenced in it. Does not affect common blocks. (Some Fortran compilers
|
||
|
|
provide this option under the name \fB\-static\fR or \fB\-save\fR.)
|
||
|
|
The default, which is \fB\-fautomatic\fR, uses the stack for local
|
||
|
|
variables smaller than the value given by \fB\-fmax\-stack\-var\-size\fR.
|
||
|
|
Use the option \fB\-frecursive\fR to use no static memory.
|
||
|
|
.IP "\fB\-ff2c\fR" 4
|
||
|
|
.IX Item "-ff2c"
|
||
|
|
Generate code designed to be compatible with code generated
|
||
|
|
by \fBg77\fR and \fBf2c\fR.
|
||
|
|
.Sp
|
||
|
|
The calling conventions used by \fBg77\fR (originally implemented
|
||
|
|
in \fBf2c\fR) require functions that return type
|
||
|
|
default \f(CW\*(C`REAL\*(C'\fR to actually return the C type \f(CW\*(C`double\*(C'\fR, and
|
||
|
|
functions that return type \f(CW\*(C`COMPLEX\*(C'\fR to return the values via an
|
||
|
|
extra argument in the calling sequence that points to where to
|
||
|
|
store the return value. Under the default \s-1GNU\s0 calling conventions, such
|
||
|
|
functions simply return their results as they would in \s-1GNU\s0
|
||
|
|
C\-\-\-default \f(CW\*(C`REAL\*(C'\fR functions return the C type \f(CW\*(C`float\*(C'\fR, and
|
||
|
|
\&\f(CW\*(C`COMPLEX\*(C'\fR functions return the \s-1GNU C\s0 type \f(CW\*(C`complex\*(C'\fR.
|
||
|
|
Additionally, this option implies the \fB\-fsecond\-underscore\fR
|
||
|
|
option, unless \fB\-fno\-second\-underscore\fR is explicitly requested.
|
||
|
|
.Sp
|
||
|
|
This does not affect the generation of code that interfaces with
|
||
|
|
the \fBlibgfortran\fR library.
|
||
|
|
.Sp
|
||
|
|
\&\fICaution:\fR It is not a good idea to mix Fortran code compiled with
|
||
|
|
\&\fB\-ff2c\fR with code compiled with the default \fB\-fno\-f2c\fR
|
||
|
|
calling conventions as, calling \f(CW\*(C`COMPLEX\*(C'\fR or default \f(CW\*(C`REAL\*(C'\fR
|
||
|
|
functions between program parts which were compiled with different
|
||
|
|
calling conventions will break at execution time.
|
||
|
|
.Sp
|
||
|
|
\&\fICaution:\fR This will break code which passes intrinsic functions
|
||
|
|
of type default \f(CW\*(C`REAL\*(C'\fR or \f(CW\*(C`COMPLEX\*(C'\fR as actual arguments, as
|
||
|
|
the library implementations use the \fB\-fno\-f2c\fR calling conventions.
|
||
|
|
.IP "\fB\-fno\-underscoring\fR" 4
|
||
|
|
.IX Item "-fno-underscoring"
|
||
|
|
Do not transform names of entities specified in the Fortran
|
||
|
|
source file by appending underscores to them.
|
||
|
|
.Sp
|
||
|
|
With \fB\-funderscoring\fR in effect, \s-1GNU\s0 Fortran appends one
|
||
|
|
underscore to external names with no underscores. This is done to ensure
|
||
|
|
compatibility with code produced by many \s-1UNIX\s0 Fortran compilers.
|
||
|
|
.Sp
|
||
|
|
\&\fICaution\fR: The default behavior of \s-1GNU\s0 Fortran is
|
||
|
|
incompatible with \fBf2c\fR and \fBg77\fR, please use the
|
||
|
|
\&\fB\-ff2c\fR option if you want object files compiled with
|
||
|
|
\&\s-1GNU\s0 Fortran to be compatible with object code created with these
|
||
|
|
tools.
|
||
|
|
.Sp
|
||
|
|
Use of \fB\-fno\-underscoring\fR is not recommended unless you are
|
||
|
|
experimenting with issues such as integration of \s-1GNU\s0 Fortran into
|
||
|
|
existing system environments (vis\-a\*`\-vis existing libraries, tools,
|
||
|
|
and so on).
|
||
|
|
.Sp
|
||
|
|
For example, with \fB\-funderscoring\fR, and assuming that \f(CW\*(C`j()\*(C'\fR and
|
||
|
|
\&\f(CW\*(C`max_count()\*(C'\fR are external functions while \f(CW\*(C`my_var\*(C'\fR and
|
||
|
|
\&\f(CW\*(C`lvar\*(C'\fR are local variables, a statement like
|
||
|
|
.Sp
|
||
|
|
.Vb 1
|
||
|
|
\& I = J() + MAX_COUNT (MY_VAR, LVAR)
|
||
|
|
.Ve
|
||
|
|
.Sp
|
||
|
|
is implemented as something akin to:
|
||
|
|
.Sp
|
||
|
|
.Vb 1
|
||
|
|
\& i = j_() + max_count_\|_(&my_var_\|_, &lvar);
|
||
|
|
.Ve
|
||
|
|
.Sp
|
||
|
|
With \fB\-fno\-underscoring\fR, the same statement is implemented as:
|
||
|
|
.Sp
|
||
|
|
.Vb 1
|
||
|
|
\& i = j() + max_count(&my_var, &lvar);
|
||
|
|
.Ve
|
||
|
|
.Sp
|
||
|
|
Use of \fB\-fno\-underscoring\fR allows direct specification of
|
||
|
|
user-defined names while debugging and when interfacing \s-1GNU\s0 Fortran
|
||
|
|
code with other languages.
|
||
|
|
.Sp
|
||
|
|
Note that just because the names match does \fInot\fR mean that the
|
||
|
|
interface implemented by \s-1GNU\s0 Fortran for an external name matches the
|
||
|
|
interface implemented by some other language for that same name.
|
||
|
|
That is, getting code produced by \s-1GNU\s0 Fortran to link to code produced
|
||
|
|
by some other compiler using this or any other method can be only a
|
||
|
|
small part of the overall solution\-\-\-getting the code generated by
|
||
|
|
both compilers to agree on issues other than naming can require
|
||
|
|
significant effort, and, unlike naming disagreements, linkers normally
|
||
|
|
cannot detect disagreements in these other areas.
|
||
|
|
.Sp
|
||
|
|
Also, note that with \fB\-fno\-underscoring\fR, the lack of appended
|
||
|
|
underscores introduces the very real possibility that a user-defined
|
||
|
|
external name will conflict with a name in a system library, which
|
||
|
|
could make finding unresolved-reference bugs quite difficult in some
|
||
|
|
cases\-\-\-they might occur at program run time, and show up only as
|
||
|
|
buggy behavior at run time.
|
||
|
|
.Sp
|
||
|
|
In future versions of \s-1GNU\s0 Fortran we hope to improve naming and linking
|
||
|
|
issues so that debugging always involves using the names as they appear
|
||
|
|
in the source, even if the names as seen by the linker are mangled to
|
||
|
|
prevent accidental linking between procedures with incompatible
|
||
|
|
interfaces.
|
||
|
|
.IP "\fB\-fsecond\-underscore\fR" 4
|
||
|
|
.IX Item "-fsecond-underscore"
|
||
|
|
By default, \s-1GNU\s0 Fortran appends an underscore to external
|
||
|
|
names. If this option is used \s-1GNU\s0 Fortran appends two
|
||
|
|
underscores to names with underscores and one underscore to external names
|
||
|
|
with no underscores. \s-1GNU\s0 Fortran also appends two underscores to
|
||
|
|
internal names with underscores to avoid naming collisions with external
|
||
|
|
names.
|
||
|
|
.Sp
|
||
|
|
This option has no effect if \fB\-fno\-underscoring\fR is
|
||
|
|
in effect. It is implied by the \fB\-ff2c\fR option.
|
||
|
|
.Sp
|
||
|
|
Otherwise, with this option, an external name such as \f(CW\*(C`MAX_COUNT\*(C'\fR
|
||
|
|
is implemented as a reference to the link-time external symbol
|
||
|
|
\&\f(CW\*(C`max_count_\|_\*(C'\fR, instead of \f(CW\*(C`max_count_\*(C'\fR. This is required
|
||
|
|
for compatibility with \fBg77\fR and \fBf2c\fR, and is implied
|
||
|
|
by use of the \fB\-ff2c\fR option.
|
||
|
|
.IP "\fB\-fcoarray=\fR\fI<keyword>\fR" 4
|
||
|
|
.IX Item "-fcoarray=<keyword>"
|
||
|
|
.RS 4
|
||
|
|
.PD 0
|
||
|
|
.IP "\fBnone\fR" 4
|
||
|
|
.IX Item "none"
|
||
|
|
.PD
|
||
|
|
Disable coarray support; using coarray declarations and image-control
|
||
|
|
statements will produce a compile-time error. (Default)
|
||
|
|
.IP "\fBsingle\fR" 4
|
||
|
|
.IX Item "single"
|
||
|
|
Single-image mode, i.e. \f(CW\*(C`num_images()\*(C'\fR is always one.
|
||
|
|
.IP "\fBlib\fR" 4
|
||
|
|
.IX Item "lib"
|
||
|
|
Library-based coarray parallelization; a suitable \s-1GNU\s0 Fortran coarray
|
||
|
|
library needs to be linked.
|
||
|
|
.RE
|
||
|
|
.RS 4
|
||
|
|
.RE
|
||
|
|
.IP "\fB\-fcheck=\fR\fI<keyword>\fR" 4
|
||
|
|
.IX Item "-fcheck=<keyword>"
|
||
|
|
Enable the generation of run-time checks; the argument shall be
|
||
|
|
a comma-delimited list of the following keywords. Prefixing a check with
|
||
|
|
\&\fBno\-\fR disables it if it was activated by a previous specification.
|
||
|
|
.RS 4
|
||
|
|
.IP "\fBall\fR" 4
|
||
|
|
.IX Item "all"
|
||
|
|
Enable all run-time test of \fB\-fcheck\fR.
|
||
|
|
.IP "\fBarray-temps\fR" 4
|
||
|
|
.IX Item "array-temps"
|
||
|
|
Warns at run time when for passing an actual argument a temporary array
|
||
|
|
had to be generated. The information generated by this warning is
|
||
|
|
sometimes useful in optimization, in order to avoid such temporaries.
|
||
|
|
.Sp
|
||
|
|
Note: The warning is only printed once per location.
|
||
|
|
.IP "\fBbounds\fR" 4
|
||
|
|
.IX Item "bounds"
|
||
|
|
Enable generation of run-time checks for array subscripts
|
||
|
|
and against the declared minimum and maximum values. It also
|
||
|
|
checks array indices for assumed and deferred
|
||
|
|
shape arrays against the actual allocated bounds and ensures that all string
|
||
|
|
lengths are equal for character array constructors without an explicit
|
||
|
|
typespec.
|
||
|
|
.Sp
|
||
|
|
Some checks require that \fB\-fcheck=bounds\fR is set for
|
||
|
|
the compilation of the main program.
|
||
|
|
.Sp
|
||
|
|
Note: In the future this may also include other forms of checking, e.g.,
|
||
|
|
checking substring references.
|
||
|
|
.IP "\fBdo\fR" 4
|
||
|
|
.IX Item "do"
|
||
|
|
Enable generation of run-time checks for invalid modification of loop
|
||
|
|
iteration variables.
|
||
|
|
.IP "\fBmem\fR" 4
|
||
|
|
.IX Item "mem"
|
||
|
|
Enable generation of run-time checks for memory allocation.
|
||
|
|
Note: This option does not affect explicit allocations using the
|
||
|
|
\&\f(CW\*(C`ALLOCATE\*(C'\fR statement, which will be always checked.
|
||
|
|
.IP "\fBpointer\fR" 4
|
||
|
|
.IX Item "pointer"
|
||
|
|
Enable generation of run-time checks for pointers and allocatables.
|
||
|
|
.IP "\fBrecursion\fR" 4
|
||
|
|
.IX Item "recursion"
|
||
|
|
Enable generation of run-time checks for recursively called subroutines and
|
||
|
|
functions which are not marked as recursive. See also \fB\-frecursive\fR.
|
||
|
|
Note: This check does not work for OpenMP programs and is disabled if used
|
||
|
|
together with \fB\-frecursive\fR and \fB\-fopenmp\fR.
|
||
|
|
.RE
|
||
|
|
.RS 4
|
||
|
|
.Sp
|
||
|
|
Example: Assuming you have a file \fIfoo.f90\fR, the command
|
||
|
|
.Sp
|
||
|
|
.Vb 1
|
||
|
|
\& gfortran \-fcheck=all,no\-array\-temps foo.f90
|
||
|
|
.Ve
|
||
|
|
.Sp
|
||
|
|
will compile the file with all checks enabled as specified above except
|
||
|
|
warnings for generated array temporaries.
|
||
|
|
.RE
|
||
|
|
.IP "\fB\-fbounds\-check\fR" 4
|
||
|
|
.IX Item "-fbounds-check"
|
||
|
|
Deprecated alias for \fB\-fcheck=bounds\fR.
|
||
|
|
.IP "\fB\-fcheck\-array\-temporaries\fR" 4
|
||
|
|
.IX Item "-fcheck-array-temporaries"
|
||
|
|
Deprecated alias for \fB\-fcheck=array\-temps\fR.
|
||
|
|
.IP "\fB\-fmax\-array\-constructor=\fR\fIn\fR" 4
|
||
|
|
.IX Item "-fmax-array-constructor=n"
|
||
|
|
This option can be used to increase the upper limit permitted in
|
||
|
|
array constructors. The code below requires this option to expand
|
||
|
|
the array at compile time.
|
||
|
|
.Sp
|
||
|
|
.Vb 7
|
||
|
|
\& program test
|
||
|
|
\& implicit none
|
||
|
|
\& integer j
|
||
|
|
\& integer, parameter :: n = 100000
|
||
|
|
\& integer, parameter :: i(n) = (/ (2*j, j = 1, n) /)
|
||
|
|
\& print \*(Aq(10(I0,1X))\*(Aq, i
|
||
|
|
\& end program test
|
||
|
|
.Ve
|
||
|
|
.Sp
|
||
|
|
\&\fICaution: This option can lead to long compile times and excessively
|
||
|
|
large object files.\fR
|
||
|
|
.Sp
|
||
|
|
The default value for \fIn\fR is 65535.
|
||
|
|
.IP "\fB\-fmax\-stack\-var\-size=\fR\fIn\fR" 4
|
||
|
|
.IX Item "-fmax-stack-var-size=n"
|
||
|
|
This option specifies the size in bytes of the largest array that will be put
|
||
|
|
on the stack; if the size is exceeded static memory is used (except in
|
||
|
|
procedures marked as \s-1RECURSIVE\s0). Use the option \fB\-frecursive\fR to
|
||
|
|
allow for recursive procedures which do not have a \s-1RECURSIVE\s0 attribute or
|
||
|
|
for parallel programs. Use \fB\-fno\-automatic\fR to never use the stack.
|
||
|
|
.Sp
|
||
|
|
This option currently only affects local arrays declared with constant
|
||
|
|
bounds, and may not apply to all character variables.
|
||
|
|
Future versions of \s-1GNU\s0 Fortran may improve this behavior.
|
||
|
|
.Sp
|
||
|
|
The default value for \fIn\fR is 32768.
|
||
|
|
.IP "\fB\-fstack\-arrays\fR" 4
|
||
|
|
.IX Item "-fstack-arrays"
|
||
|
|
Adding this option will make the Fortran compiler put all local arrays,
|
||
|
|
even those of unknown size onto stack memory. If your program uses very
|
||
|
|
large local arrays it is possible that you will have to extend your runtime
|
||
|
|
limits for stack memory on some operating systems. This flag is enabled
|
||
|
|
by default at optimization level \fB\-Ofast\fR.
|
||
|
|
.IP "\fB\-fpack\-derived\fR" 4
|
||
|
|
.IX Item "-fpack-derived"
|
||
|
|
This option tells \s-1GNU\s0 Fortran to pack derived type members as closely as
|
||
|
|
possible. Code compiled with this option is likely to be incompatible
|
||
|
|
with code compiled without this option, and may execute slower.
|
||
|
|
.IP "\fB\-frepack\-arrays\fR" 4
|
||
|
|
.IX Item "-frepack-arrays"
|
||
|
|
In some circumstances \s-1GNU\s0 Fortran may pass assumed shape array
|
||
|
|
sections via a descriptor describing a noncontiguous area of memory.
|
||
|
|
This option adds code to the function prologue to repack the data into
|
||
|
|
a contiguous block at runtime.
|
||
|
|
.Sp
|
||
|
|
This should result in faster accesses to the array. However it can introduce
|
||
|
|
significant overhead to the function call, especially when the passed data
|
||
|
|
is noncontiguous.
|
||
|
|
.IP "\fB\-fshort\-enums\fR" 4
|
||
|
|
.IX Item "-fshort-enums"
|
||
|
|
This option is provided for interoperability with C code that was
|
||
|
|
compiled with the \fB\-fshort\-enums\fR option. It will make
|
||
|
|
\&\s-1GNU\s0 Fortran choose the smallest \f(CW\*(C`INTEGER\*(C'\fR kind a given
|
||
|
|
enumerator set will fit in, and give all its enumerators this kind.
|
||
|
|
.IP "\fB\-fexternal\-blas\fR" 4
|
||
|
|
.IX Item "-fexternal-blas"
|
||
|
|
This option will make \fBgfortran\fR generate calls to \s-1BLAS\s0 functions
|
||
|
|
for some matrix operations like \f(CW\*(C`MATMUL\*(C'\fR, instead of using our own
|
||
|
|
algorithms, if the size of the matrices involved is larger than a given
|
||
|
|
limit (see \fB\-fblas\-matmul\-limit\fR). This may be profitable if an
|
||
|
|
optimized vendor \s-1BLAS\s0 library is available. The \s-1BLAS\s0 library will have
|
||
|
|
to be specified at link time.
|
||
|
|
.IP "\fB\-fblas\-matmul\-limit=\fR\fIn\fR" 4
|
||
|
|
.IX Item "-fblas-matmul-limit=n"
|
||
|
|
Only significant when \fB\-fexternal\-blas\fR is in effect.
|
||
|
|
Matrix multiplication of matrices with size larger than (or equal to) \fIn\fR
|
||
|
|
will be performed by calls to \s-1BLAS\s0 functions, while others will be
|
||
|
|
handled by \fBgfortran\fR internal algorithms. If the matrices
|
||
|
|
involved are not square, the size comparison is performed using the
|
||
|
|
geometric mean of the dimensions of the argument and result matrices.
|
||
|
|
.Sp
|
||
|
|
The default value for \fIn\fR is 30.
|
||
|
|
.IP "\fB\-finline\-matmul\-limit=\fR\fIn\fR" 4
|
||
|
|
.IX Item "-finline-matmul-limit=n"
|
||
|
|
When front-end optimiztion is active, some calls to the \f(CW\*(C`MATMUL\*(C'\fR
|
||
|
|
intrinsic function will be inlined. This may result in code size
|
||
|
|
increase if the size of the matrix cannot be determined at compile
|
||
|
|
time, as code for both cases is generated. Setting
|
||
|
|
\&\f(CW\*(C`\-finline\-matmul\-limit=0\*(C'\fR will disable inlining in all cases.
|
||
|
|
Setting this option with a value of \fIn\fR will produce inline code
|
||
|
|
for matrices with size up to \fIn\fR. If the matrices involved are not
|
||
|
|
square, the size comparison is performed using the geometric mean of
|
||
|
|
the dimensions of the argument and result matrices.
|
||
|
|
.Sp
|
||
|
|
The default value for \fIn\fR is the value specified for
|
||
|
|
\&\f(CW\*(C`\-fblas\-matmul\-limit\*(C'\fR if this option is specified, or unlimitited
|
||
|
|
otherwise.
|
||
|
|
.IP "\fB\-frecursive\fR" 4
|
||
|
|
.IX Item "-frecursive"
|
||
|
|
Allow indirect recursion by forcing all local arrays to be allocated
|
||
|
|
on the stack. This flag cannot be used together with
|
||
|
|
\&\fB\-fmax\-stack\-var\-size=\fR or \fB\-fno\-automatic\fR.
|
||
|
|
.IP "\fB\-finit\-local\-zero\fR" 4
|
||
|
|
.IX Item "-finit-local-zero"
|
||
|
|
.PD 0
|
||
|
|
.IP "\fB\-finit\-integer=\fR\fIn\fR" 4
|
||
|
|
.IX Item "-finit-integer=n"
|
||
|
|
.IP "\fB\-finit\-real=\fR\fI<zero|inf|\-inf|nan|snan>\fR" 4
|
||
|
|
.IX Item "-finit-real=<zero|inf|-inf|nan|snan>"
|
||
|
|
.IP "\fB\-finit\-logical=\fR\fI<true|false>\fR" 4
|
||
|
|
.IX Item "-finit-logical=<true|false>"
|
||
|
|
.IP "\fB\-finit\-character=\fR\fIn\fR" 4
|
||
|
|
.IX Item "-finit-character=n"
|
||
|
|
.PD
|
||
|
|
The \fB\-finit\-local\-zero\fR option instructs the compiler to
|
||
|
|
initialize local \f(CW\*(C`INTEGER\*(C'\fR, \f(CW\*(C`REAL\*(C'\fR, and \f(CW\*(C`COMPLEX\*(C'\fR
|
||
|
|
variables to zero, \f(CW\*(C`LOGICAL\*(C'\fR variables to false, and
|
||
|
|
\&\f(CW\*(C`CHARACTER\*(C'\fR variables to a string of null bytes. Finer-grained
|
||
|
|
initialization options are provided by the
|
||
|
|
\&\fB\-finit\-integer=\fR\fIn\fR,
|
||
|
|
\&\fB\-finit\-real=\fR\fI<zero|inf|\-inf|nan|snan>\fR (which also initializes
|
||
|
|
the real and imaginary parts of local \f(CW\*(C`COMPLEX\*(C'\fR variables),
|
||
|
|
\&\fB\-finit\-logical=\fR\fI<true|false>\fR, and
|
||
|
|
\&\fB\-finit\-character=\fR\fIn\fR (where \fIn\fR is an \s-1ASCII\s0 character
|
||
|
|
value) options. These options do not initialize
|
||
|
|
.RS 4
|
||
|
|
.IP "*" 4
|
||
|
|
allocatable arrays
|
||
|
|
.IP "*" 4
|
||
|
|
components of derived type variables
|
||
|
|
.IP "*" 4
|
||
|
|
variables that appear in an \f(CW\*(C`EQUIVALENCE\*(C'\fR statement.
|
||
|
|
.RE
|
||
|
|
.RS 4
|
||
|
|
.Sp
|
||
|
|
(These limitations may be removed in future releases).
|
||
|
|
.Sp
|
||
|
|
Note that the \fB\-finit\-real=nan\fR option initializes \f(CW\*(C`REAL\*(C'\fR
|
||
|
|
and \f(CW\*(C`COMPLEX\*(C'\fR variables with a quiet NaN. For a signalling NaN
|
||
|
|
use \fB\-finit\-real=snan\fR; note, however, that compile-time
|
||
|
|
optimizations may convert them into quiet NaN and that trapping
|
||
|
|
needs to be enabled (e.g. via \fB\-ffpe\-trap\fR).
|
||
|
|
.Sp
|
||
|
|
Finally, note that enabling any of the \fB\-finit\-*\fR options will
|
||
|
|
silence warnings that would have been emitted by \fB\-Wuninitialized\fR
|
||
|
|
for the affected local variables.
|
||
|
|
.RE
|
||
|
|
.IP "\fB\-falign\-commons\fR" 4
|
||
|
|
.IX Item "-falign-commons"
|
||
|
|
By default, \fBgfortran\fR enforces proper alignment of all variables in a
|
||
|
|
\&\f(CW\*(C`COMMON\*(C'\fR block by padding them as needed. On certain platforms this is mandatory,
|
||
|
|
on others it increases performance. If a \f(CW\*(C`COMMON\*(C'\fR block is not declared with
|
||
|
|
consistent data types everywhere, this padding can cause trouble, and
|
||
|
|
\&\fB\-fno\-align\-commons\fR can be used to disable automatic alignment. The
|
||
|
|
same form of this option should be used for all files that share a \f(CW\*(C`COMMON\*(C'\fR block.
|
||
|
|
To avoid potential alignment issues in \f(CW\*(C`COMMON\*(C'\fR blocks, it is recommended to order
|
||
|
|
objects from largest to smallest.
|
||
|
|
.IP "\fB\-fno\-protect\-parens\fR" 4
|
||
|
|
.IX Item "-fno-protect-parens"
|
||
|
|
By default the parentheses in expression are honored for all optimization
|
||
|
|
levels such that the compiler does not do any re-association. Using
|
||
|
|
\&\fB\-fno\-protect\-parens\fR allows the compiler to reorder \f(CW\*(C`REAL\*(C'\fR and
|
||
|
|
\&\f(CW\*(C`COMPLEX\*(C'\fR expressions to produce faster code. Note that for the re-association
|
||
|
|
optimization \fB\-fno\-signed\-zeros\fR and \fB\-fno\-trapping\-math\fR
|
||
|
|
need to be in effect. The parentheses protection is enabled by default, unless
|
||
|
|
\&\fB\-Ofast\fR is given.
|
||
|
|
.IP "\fB\-frealloc\-lhs\fR" 4
|
||
|
|
.IX Item "-frealloc-lhs"
|
||
|
|
An allocatable left-hand side of an intrinsic assignment is automatically
|
||
|
|
(re)allocated if it is either unallocated or has a different shape. The
|
||
|
|
option is enabled by default except when \fB\-std=f95\fR is given. See
|
||
|
|
also \fB\-Wrealloc\-lhs\fR.
|
||
|
|
.IP "\fB\-faggressive\-function\-elimination\fR" 4
|
||
|
|
.IX Item "-faggressive-function-elimination"
|
||
|
|
Functions with identical argument lists are eliminated within
|
||
|
|
statements, regardless of whether these functions are marked
|
||
|
|
\&\f(CW\*(C`PURE\*(C'\fR or not. For example, in
|
||
|
|
.Sp
|
||
|
|
.Vb 1
|
||
|
|
\& a = f(b,c) + f(b,c)
|
||
|
|
.Ve
|
||
|
|
.Sp
|
||
|
|
there will only be a single call to \f(CW\*(C`f\*(C'\fR. This option only works
|
||
|
|
if \fB\-ffrontend\-optimize\fR is in effect.
|
||
|
|
.IP "\fB\-ffrontend\-optimize\fR" 4
|
||
|
|
.IX Item "-ffrontend-optimize"
|
||
|
|
This option performs front-end optimization, based on manipulating
|
||
|
|
parts the Fortran parse tree. Enabled by default by any \fB\-O\fR
|
||
|
|
option. Optimizations enabled by this option include inlining calls
|
||
|
|
to \f(CW\*(C`MATMUL\*(C'\fR, elimination of identical function calls within
|
||
|
|
expressions, removing unnecessary calls to \f(CW\*(C`TRIM\*(C'\fR in comparisons
|
||
|
|
and assignments and replacing \f(CWTRIM(a)\fR with
|
||
|
|
\&\f(CW\*(C`a(1:LEN_TRIM(a))\*(C'\fR. It can be deselected by specifying
|
||
|
|
\&\fB\-fno\-frontend\-optimize\fR.
|
||
|
|
.SH "ENVIRONMENT"
|
||
|
|
.IX Header "ENVIRONMENT"
|
||
|
|
The \fBgfortran\fR compiler currently does not make use of any environment
|
||
|
|
variables to control its operation above and beyond those
|
||
|
|
that affect the operation of \fBgcc\fR.
|
||
|
|
.SH "BUGS"
|
||
|
|
.IX Header "BUGS"
|
||
|
|
For instructions on reporting bugs, see
|
||
|
|
<\fBhttp://gcc.gnu.org/bugs.html\fR>.
|
||
|
|
.SH "SEE ALSO"
|
||
|
|
.IX Header "SEE ALSO"
|
||
|
|
\&\fIgpl\fR\|(7), \fIgfdl\fR\|(7), \fIfsf\-funding\fR\|(7),
|
||
|
|
\&\fIcpp\fR\|(1), \fIgcov\fR\|(1), \fIgcc\fR\|(1), \fIas\fR\|(1), \fIld\fR\|(1), \fIgdb\fR\|(1), \fIadb\fR\|(1), \fIdbx\fR\|(1), \fIsdb\fR\|(1)
|
||
|
|
and the Info entries for \fIgcc\fR, \fIcpp\fR, \fIgfortran\fR, \fIas\fR,
|
||
|
|
\&\fIld\fR, \fIbinutils\fR and \fIgdb\fR.
|
||
|
|
.SH "AUTHOR"
|
||
|
|
.IX Header "AUTHOR"
|
||
|
|
See the Info entry for \fBgfortran\fR for contributors to \s-1GCC\s0 and
|
||
|
|
\&\s-1GNU\s0 Fortran.
|
||
|
|
.SH "COPYRIGHT"
|
||
|
|
.IX Header "COPYRIGHT"
|
||
|
|
Copyright (c) 2004\-2016 Free Software Foundation, Inc.
|
||
|
|
.PP
|
||
|
|
Permission is granted to copy, distribute and/or modify this document
|
||
|
|
under the terms of the \s-1GNU\s0 Free Documentation License, Version 1.3 or
|
||
|
|
any later version published by the Free Software Foundation; with the
|
||
|
|
Invariant Sections being \*(L"Funding Free Software\*(R", the Front-Cover
|
||
|
|
Texts being (a) (see below), and with the Back-Cover Texts being (b)
|
||
|
|
(see below). A copy of the license is included in the \fIgfdl\fR\|(7) man page.
|
||
|
|
.PP
|
||
|
|
(a) The \s-1FSF\s0's Front-Cover Text is:
|
||
|
|
.PP
|
||
|
|
.Vb 1
|
||
|
|
\& A GNU Manual
|
||
|
|
.Ve
|
||
|
|
.PP
|
||
|
|
(b) The \s-1FSF\s0's Back-Cover Text is:
|
||
|
|
.PP
|
||
|
|
.Vb 3
|
||
|
|
\& You have freedom to copy and modify this GNU Manual, like GNU
|
||
|
|
\& software. Copies published by the Free Software Foundation raise
|
||
|
|
\& funds for GNU development.
|
||
|
|
.Ve
|