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+.ds ae a\h'-(\w'a'u*4/10)'e
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+. \" corrections for vroff
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+. \" for low resolution devices (crt and lpr)
+.if \n(.H>23 .if \n(.V>19 \
+\{\
+. ds : e
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+.\}
+.rm #[ #] #H #V #F C
+.\" ========================================================================
+.\"
+.IX Title "GFORTRAN 1"
+.TH GFORTRAN 1 "2014-04-22" "gcc-4.9.0" "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 \-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 \-fno\-fixed\-form \-fno\-range\-check
+\&\-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 \-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\-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\-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\-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.
+.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\-Wno\-tabs\fR, \fB\-Wintrinsic\-shadow\fR,
+\&\fB\-Wline\-truncation\fR, \fB\-Wtarget\-lifetime\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.
+.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.
+.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\-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 "\(bu" 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 "\(bu" 4
+A \s-1LOGICAL SELECT\s0 construct has three \s-1CASE\s0 statements.
+.IP "\(bu" 4
+A \s-1TRANSFER\s0 specifies a source that is shorter than the destination.
+.IP "\(bu" 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 "\(bu" 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\-Wno\-tabs\fR will cause
+a warning to be issued if a tab is encountered. Note, \fB\-Wno\-tabs\fR
+is active for \fB\-pedantic\fR, \fB\-std=f95\fR, \fB\-std=f2003\fR,
+\&\fB\-std=f2008\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.
+.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\-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 not included in \fB\-Wall\fR but is implied by \fB\-Wall \-Wextra\fR.
+.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 other defaults like
+\&\fB\-fcase\-lower\fR and 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.
+.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
+.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\-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 "\(bu" 4
+allocatable arrays
+.IP "\(bu" 4
+components of derived type variables
+.IP "\(bu" 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 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\-2014 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