7539316943
libf2c: * libF77/Version.c, libI77/Version.c, libU77/Version.c: Update G77 version number to 0.5.27. gcc: * README, cpp.texi, gcc.texi, version.c: Update version number to 3.1. * cpp.1, gcov.1, gcc.1: Regenerate. gcc/f: * version.c, root.texi: Update GCC version number to 3.1. Update G77 version number to 0.5.27. * BUGS, NEWS: Regenerate. From-SVN: r39901
765 lines
29 KiB
Groff
765 lines
29 KiB
Groff
.\" Automatically generated by Pod::Man version 1.1
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.\" Mon Feb 19 19:32:17 2001
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.\"
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.\" Standard preamble:
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.\" ======================================================================
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.IP "\\$1" \\$2
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..
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.\" Set up some character translations and predefined strings. \*(-- will
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.rm #[ #] #H #V #F C
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.\" ======================================================================
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.\"
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.IX Title "CPP 1"
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.TH CPP 1 "gcc-3.1" "2001-02-19" "GNU"
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.UC
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.SH "NAME"
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cpp \- The C Preprocessor
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.SH "SYNOPSIS"
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.IX Header "SYNOPSIS"
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cpp [\fB\-P\fR] [\fB\-C\fR] [\fB\-gcc\fR] [\fB\-traditional\fR]
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[\fB\-undef\fR] [\fB\-trigraphs\fR] [\fB\-pedantic\fR]
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[\fB\-W\fR\fIwarn\fR...] [\fB\-I\fR\fIdir\fR...]
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[\fB\-D\fR\fImacro\fR[=\fIdefn\fR]...] [\fB\-U\fR\fImacro\fR]
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[\fB\-A\fR\fIpredicate\fR(\fIanswer\fR)]
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[\fB\-M\fR|\fB\-MM\fR][\fB\-MG\fR][\fB\-MF\fR\fIfilename\fR]
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[\fB\-MP\fR][\fB\-MQ\fR\fItarget\fR...][\fB\-MT\fR\fItarget\fR...]
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[\fB\-x\fR \fIlanguage\fR] [\fB\-std=\fR\fIstandard\fR]
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\fIinfile\fR \fIoutfile\fR
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.PP
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Only the most useful options are listed here; see below for the remainder.
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.SH "DESCRIPTION"
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.IX Header "DESCRIPTION"
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The C preprocessor is a \fImacro processor\fR that is used automatically
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by the C compiler to transform your program before actual compilation.
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It is called a macro processor because it allows you to define
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\&\fImacros\fR, which are brief abbreviations for longer constructs.
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.PP
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The C preprocessor is intended only for macro processing of C, \*(C+ and
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Objective C source files. For macro processing of other files, you are
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strongly encouraged to use alternatives like M4, which will likely give
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you better results and avoid many problems. For example, normally the C
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preprocessor does not preserve arbitrary whitespace verbatim, but
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instead replaces each sequence with a single space.
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.PP
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For use on C-like source files, the C preprocessor provides four
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separate facilities that you can use as you see fit:
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.Ip "\(bu" 4
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Inclusion of header files. These are files of declarations that can be
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substituted into your program.
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.Ip "\(bu" 4
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Macro expansion. You can define \fImacros\fR, which are abbreviations
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for arbitrary fragments of C code, and then the C preprocessor will
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replace the macros with their definitions throughout the program.
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.Ip "\(bu" 4
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Conditional compilation. Using special preprocessing directives, you
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can include or exclude parts of the program according to various
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conditions.
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.Ip "\(bu" 4
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Line control. If you use a program to combine or rearrange source files
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into an intermediate file which is then compiled, you can use line
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control to inform the compiler of where each source line originally came
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from.
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.PP
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C preprocessors vary in some details. This manual discusses the \s-1GNU\s0 C
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preprocessor, which provides a small superset of the features of \s-1ISO\s0
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Standard C.
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.PP
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In its default mode, the \s-1GNU\s0 C preprocessor does not do a few things
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required by the standard. These are features which are rarely, if ever,
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used, and may cause surprising changes to the meaning of a program which
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does not expect them. To get strict \s-1ISO\s0 Standard C, you should use the
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\&\fB\-std=c89\fR or \fB\-std=c99\fR options, depending on which version
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of the standard you want. To get all the mandatory diagnostics, you
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must also use \fB\-pedantic\fR.
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.SH "OPTIONS"
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|
.IX Header "OPTIONS"
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The C preprocessor expects two file names as arguments, \fIinfile\fR and
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\&\fIoutfile\fR. The preprocessor reads \fIinfile\fR together with any
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other files it specifies with \fB#include\fR. All the output generated
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by the combined input files is written in \fIoutfile\fR.
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.PP
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Either \fIinfile\fR or \fIoutfile\fR may be \fB-\fR, which as
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\&\fIinfile\fR means to read from standard input and as \fIoutfile\fR
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|
means to write to standard output. Also, if either file is omitted, it
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means the same as if \fB-\fR had been specified for that file.
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.PP
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|
Here is a table of command options accepted by the C preprocessor.
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These options can also be given when compiling a C program; they are
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passed along automatically to the preprocessor when it is invoked by the
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compiler.
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|
.Ip "\fB\-P\fR" 4
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.IX Item "-P"
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Inhibit generation of \fB#\fR\-lines with line-number information in the
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output from the preprocessor. This might be useful when running the
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preprocessor on something that is not C code and will be sent to a
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program which might be confused by the \fB#\fR\-lines.
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.Ip "\fB\-C\fR" 4
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.IX Item "-C"
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|
Do not discard comments. All comments are passed through to the output
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file, except for comments in processed directives, which are deleted
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along with the directive. Comments appearing in the expansion list of a
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macro will be preserved, and appear in place wherever the macro is
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invoked.
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.Sp
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You should be prepared for side effects when using \fB\-C\fR; it causes
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the preprocessor to treat comments as tokens in their own right. For
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example, macro redefinitions that were trivial when comments were
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replaced by a single space might become significant when comments are
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retained. Also, comments appearing at the start of what would be a
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directive line have the effect of turning that line into an ordinary
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source line, since the first token on the line is no longer a \fB#\fR.
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.Ip "\fB\-traditional\fR" 4
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.IX Item "-traditional"
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Try to imitate the behavior of old-fashioned C, as opposed to \s-1ISO\s0 C.
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.RS 4
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.Ip "\(bu" 4
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|
Traditional macro expansion pays no attention to single-quote or
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double-quote characters; macro argument symbols are replaced by the
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argument values even when they appear within apparent string or
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character constants.
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.Ip "\(bu" 4
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|
Traditionally, it is permissible for a macro expansion to end in the
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middle of a string or character constant. The constant continues into
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the text surrounding the macro call.
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|
.Ip "\(bu" 4
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|
However, traditionally the end of the line terminates a string or
|
|
character constant, with no error.
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|
.Ip "\(bu" 4
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|
In traditional C, a comment is equivalent to no text at all. (In \s-1ISO\s0
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C, a comment counts as whitespace.)
|
|
.Ip "\(bu" 4
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|
Traditional C does not have the concept of a ``preprocessing number''.
|
|
It considers \fB1.0e+4\fR to be three tokens: \fB1.0e\fR, \fB+\fR,
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and \fB4\fR.
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.Ip "\(bu" 4
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|
A macro is not suppressed within its own definition, in traditional C.
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|
Thus, any macro that is used recursively inevitably causes an error.
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|
.Ip "\(bu" 4
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The character \fB#\fR has no special meaning within a macro definition
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in traditional C.
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|
.Ip "\(bu" 4
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|
In traditional C, the text at the end of a macro expansion can run
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together with the text after the macro call, to produce a single token.
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(This is impossible in \s-1ISO\s0 C.)
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.Ip "\(bu" 4
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None of the \s-1GNU\s0 extensions to the preprocessor are available in
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\&\fB\-traditional\fR mode.
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.RE
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.RS 4
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.Sp
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Use the \fB\-traditional\fR option when preprocessing Fortran code, so
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that single-quotes and double-quotes within Fortran comment lines (which
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are generally not recognized as such by the preprocessor) do not cause
|
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diagnostics about unterminated character or string constants.
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.Sp
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However, this option does not prevent diagnostics about unterminated
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comments when a C-style comment appears to start, but not end, within
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Fortran-style commentary.
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.Sp
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So, the following Fortran comment lines are accepted with
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\&\fB\-traditional\fR:
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.Sp
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.Vb 3
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\& C This isn't an unterminated character constant
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\& C Neither is "20000000000, an octal constant
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\& C in some dialects of Fortran
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.Ve
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However, this type of comment line will likely produce a diagnostic, or
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at least unexpected output from the preprocessor, due to the
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unterminated comment:
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.Sp
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.Vb 2
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\& C Some Fortran compilers accept /* as starting
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\& C an inline comment.
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.Ve
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Note that \f(CW\*(C`g77\*(C'\fR automatically supplies the \fB\-traditional\fR
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option when it invokes the preprocessor. However, a future version of
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\&\f(CW\*(C`g77\*(C'\fR might use a different, more-Fortran-aware preprocessor in
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place of \f(CW\*(C`cpp\*(C'\fR.
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.RE
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.Ip "\fB\-trigraphs\fR" 4
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.IX Item "-trigraphs"
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|
Process \s-1ISO\s0 standard trigraph sequences. These are three-character
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sequences, all starting with \fB??\fR, that are defined by \s-1ISO\s0 C to
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stand for single characters. For example, \fB??/\fR stands for
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\&\fB\e\fR, so \fB'??/n'\fR is a character constant for a newline. By
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default, \s-1GCC\s0 ignores trigraphs, but in standard-conforming modes it
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converts them. See the \fB\-std\fR option.
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.Sp
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The nine trigraph sequences are
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.RS 4
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.Ip "\fB??(\fR" 4
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.IX Item "??("
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-> \fB[\fR
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.Ip "\fB??)\fR" 4
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.IX Item "??)"
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-> \fB]\fR
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.Ip "\fB??<\fR" 4
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.IX Item "??<"
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-> \fB{\fR
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.Ip "\fB??>\fR" 4
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.IX Item "??>"
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-> \fB}\fR
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.Ip "\fB??=\fR" 4
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.IX Item "??="
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-> \fB#\fR
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.Ip "\fB??/\fR" 4
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.IX Item "??/"
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-> \fB\e\fR
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.Ip "\fB??'\fR" 4
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.IX Item "??'"
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-> \fB^\fR
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.Ip "\fB??!\fR" 4
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|
.IX Item "??!"
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-> \fB|\fR
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.Ip "\fB??-\fR" 4
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.IX Item "??-"
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-> \fB~\fR
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.RE
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.RS 4
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.Sp
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Trigraph support is not popular, so many compilers do not implement it
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properly. Portable code should not rely on trigraphs being either
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converted or ignored.
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.RE
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.Ip "\fB\-pedantic\fR" 4
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.IX Item "-pedantic"
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|
Issue warnings required by the \s-1ISO\s0 C standard in certain cases such
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as when text other than a comment follows \fB#else\fR or \fB#endif\fR.
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.Ip "\fB\-pedantic-errors\fR" 4
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.IX Item "-pedantic-errors"
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Like \fB\-pedantic\fR, except that errors are produced rather than
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warnings.
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.Ip "\fB\-Wcomment\fR" 4
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.IX Item "-Wcomment"
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.PD 0
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.Ip "\fB\-Wcomments\fR" 4
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.IX Item "-Wcomments"
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.PD
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(Both forms have the same effect).
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Warn whenever a comment-start sequence \fB/*\fR appears in a \fB/*\fR
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comment, or whenever a backslash-newline appears in a \fB//\fR comment.
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.Ip "\fB\-Wtrigraphs\fR" 4
|
|
.IX Item "-Wtrigraphs"
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|
Warn if any trigraphs are encountered. This option used to take effect
|
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only if \fB\-trigraphs\fR was also specified, but now works
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independently. Warnings are not given for trigraphs within comments, as
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we feel this is obnoxious.
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.Ip "\fB\-Wwhite-space\fR" 4
|
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.IX Item "-Wwhite-space"
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Warn about possible white space confusion, e.g. white space between a
|
|
backslash and a newline.
|
|
.Ip "\fB\-Wall\fR" 4
|
|
.IX Item "-Wall"
|
|
Requests \fB\-Wcomment\fR, \fB\-Wtrigraphs\fR, and \fB\-Wwhite-space\fR
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(but not \fB\-Wtraditional\fR or \fB\-Wundef\fR).
|
|
.Ip "\fB\-Wtraditional\fR" 4
|
|
.IX Item "-Wtraditional"
|
|
Warn about certain constructs that behave differently in traditional and
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|
\&\s-1ISO\s0 C.
|
|
.RS 4
|
|
.Ip "\(bu" 4
|
|
Macro parameters that appear within string literals in the macro body.
|
|
In traditional C macro replacement takes place within string literals,
|
|
but does not in \s-1ISO\s0 C.
|
|
.Ip "\(bu" 4
|
|
In traditional C, some preprocessor directives did not exist.
|
|
Traditional preprocessors would only consider a line to be a directive
|
|
if the \fB#\fR appeared in column 1 on the line. Therefore
|
|
\&\fB\-Wtraditional\fR warns about directives that traditional C
|
|
understands but would ignore because the \fB#\fR does not appear as the
|
|
first character on the line. It also suggests you hide directives like
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|
\&\fB#pragma\fR not understood by traditional C by indenting them. Some
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traditional implementations would not recognise \fB#elif\fR, so it
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suggests avoiding it altogether.
|
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.Ip "\(bu" 4
|
|
A function-like macro that appears without arguments.
|
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.Ip "\(bu" 4
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The unary plus operator.
|
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.Ip "\(bu" 4
|
|
The `U' integer constant suffix. (Traditonal C does support the `L'
|
|
suffix on integer constants.) Note, these suffixes appear in macros
|
|
defined in the system headers of most modern systems, e.g. the _MIN/_MAX
|
|
macros in limits.h. Use of these macros can lead to spurious warnings
|
|
as they do not necessarily reflect whether the code in question is any
|
|
less portable to traditional C given that suitable backup definitions
|
|
are provided.
|
|
.RE
|
|
.RS 4
|
|
.RE
|
|
.Ip "\fB\-Wundef\fR" 4
|
|
.IX Item "-Wundef"
|
|
Warn if an undefined identifier is evaluated in an \fB#if\fR directive.
|
|
.Ip "\fB\-I\fR \fIdirectory\fR" 4
|
|
.IX Item "-I directory"
|
|
Add the directory \fIdirectory\fR to the head of the list of
|
|
directories to be searched for header files.
|
|
This can be used to override a system header file, substituting your
|
|
own version, since these directories are searched before the system
|
|
header file directories. If you use more than one \fB\-I\fR option,
|
|
the directories are scanned in left-to-right order; the standard
|
|
system directories come after.
|
|
.Ip "\fB\-I-\fR" 4
|
|
.IX Item "-I-"
|
|
Any directories specified with \fB\-I\fR options before the \fB\-I-\fR
|
|
option are searched only for the case of \fB#include "\fR\fIfile\fR\fB"\fR;
|
|
they are not searched for \fB#include <\fR\fIfile\fR\fB>\fR.
|
|
.Sp
|
|
If additional directories are specified with \fB\-I\fR options after
|
|
the \fB\-I-\fR, these directories are searched for all \fB#include\fR
|
|
directives.
|
|
.Sp
|
|
In addition, the \fB\-I-\fR option inhibits the use of the current
|
|
directory as the first search directory for \fB#include "\fR\fIfile\fR\fB"\fR.
|
|
Therefore, the current directory is searched only if it is requested
|
|
explicitly with \fB\-I.\fR. Specifying both \fB\-I-\fR and \fB\-I.\fR
|
|
allows you to control precisely which directories are searched before
|
|
the current one and which are searched after.
|
|
.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 current directory, if appropriate) are searched.
|
|
.Sp
|
|
By using both \fB\-nostdinc\fR and \fB\-I-\fR, you can limit the include-file
|
|
search path to only those directories you specify explicitly.
|
|
.Ip "\fB\-nostdinc++\fR" 4
|
|
.IX Item "-nostdinc++"
|
|
Do not search for header files in the \*(C+\-specific standard directories,
|
|
but do still search the other standard directories. (This option is
|
|
used when building the \*(C+ library.)
|
|
.Ip "\fB\-remap\fR" 4
|
|
.IX Item "-remap"
|
|
When searching for a header file in a directory, remap file names if a
|
|
file named \fIheader.gcc\fR exists in that directory. This can be used
|
|
to work around limitations of file systems with file name restrictions.
|
|
The \fIheader.gcc\fR file should contain a series of lines with two
|
|
tokens on each line: the first token is the name to map, and the second
|
|
token is the actual name to use.
|
|
.Ip "\fB\-D\fR \fIname\fR" 4
|
|
.IX Item "-D name"
|
|
Predefine \fIname\fR as a macro, with definition \fB1\fR.
|
|
.Ip "\fB\-D\fR \fIname\fR\fB=\fR\fIdefinition\fR" 4
|
|
.IX Item "-D name=definition"
|
|
Predefine \fIname\fR as a macro, with definition \fIdefinition\fR.
|
|
There are no restrictions on the contents of \fIdefinition\fR, but 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. If you use more than
|
|
one \fB\-D\fR for the same \fIname\fR, the rightmost definition takes
|
|
effect.
|
|
.Sp
|
|
Any \fB\-D\fR and \fB\-U\fR options on the command line are processed in
|
|
order, and always before \fB\-imacros\fR \fIfile\fR, regardless of the
|
|
order in which they are written.
|
|
.Ip "\fB\-U\fR \fIname\fR" 4
|
|
.IX Item "-U name"
|
|
Do not predefine \fIname\fR.
|
|
.Sp
|
|
Any \fB\-D\fR and \fB\-U\fR options on the command line are processed in
|
|
order, and always before \fB\-imacros\fR \fIfile\fR, regardless of the
|
|
order in which they are written.
|
|
.Ip "\fB\-undef\fR" 4
|
|
.IX Item "-undef"
|
|
Do not predefine any nonstandard macros.
|
|
.Ip "\fB\-gcc\fR" 4
|
|
.IX Item "-gcc"
|
|
Define the macros \fI_\|_GNUC_\|_\fR, \fI_\|_GNUC_MINOR_\|_\fR and
|
|
\&\fI_\|_GNUC_PATCHLEVEL_\|_\fR. These are defined automatically when you use
|
|
\&\fBgcc \-E\fR; you can turn them off in that case with \fB\-no-gcc\fR.
|
|
.Ip "\fB\-A\fR \fIpredicate\fR\fB=\fR\fIanswer\fR" 4
|
|
.IX Item "-A predicate=answer"
|
|
Make an assertion with the predicate \fIpredicate\fR and answer
|
|
\&\fIanswer\fR. This form is preferred to the older form \fB\-A\fR
|
|
\&\fIpredicate\fR\fB(\fR\fIanswer\fR\fB)\fR, 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"
|
|
Disable an assertion with the predicate \fIpredicate\fR and answer
|
|
\&\fIanswer\fR. Specifying no predicate, by \fB\-A-\fR or \fB\-A -\fR,
|
|
disables all predefined assertions and all assertions preceding it on
|
|
the command line; and also undefines all predefined macros and all
|
|
macros preceding it on the command line.
|
|
.Ip "\fB\-dM\fR" 4
|
|
.IX Item "-dM"
|
|
Instead of outputting the result of preprocessing, output a list of
|
|
\&\fB#define\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 \fBfoo.h\fR, the command
|
|
.Sp
|
|
.Vb 1
|
|
\& touch foo.h; cpp -dM foo.h
|
|
.Ve
|
|
will show the values of any predefined macros.
|
|
.Ip "\fB\-dD\fR" 4
|
|
.IX Item "-dD"
|
|
Like \fB\-dM\fR except in two respects: it does \fInot\fR include the
|
|
predefined macros, and it outputs \fIboth\fR the \fB#define\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\-dI\fR" 4
|
|
.IX Item "-dI"
|
|
Output \fB#include\fR directives in addition to the result of
|
|
preprocessing.
|
|
.Ip "\fB\-M\fR" 4
|
|
.IX Item "-M"
|
|
Instead of outputting the result of preprocessing, output a rule
|
|
suitable for \f(CW\*(C`make\*(C'\fR describing the dependencies of the main source
|
|
file. The preprocessor outputs one \f(CW\*(C`make\*(C'\fR rule containing the
|
|
object file name for that source file, a colon, and the names of all the
|
|
included files, including those coming from \fB\-include\fR or
|
|
\&\fB\-imacros\fR command line options. Unless specified explicitly (with
|
|
\&\fB\-MT\fR or \fB\-MQ\fR), the object file name consists of the basename
|
|
of the source file with any suffix replaced with object file suffix.
|
|
If there are many included files
|
|
then the rule is split into several lines using \fB\e\fR\-newline.
|
|
.Ip "\fB\-MM\fR" 4
|
|
.IX Item "-MM"
|
|
Like \fB\-M\fR, but mention only the files included with \fB#include
|
|
"\fR\fIfile\fR\fB"\fR or with \fB\-include\fR or \fB\-imacros\fR command line
|
|
options. System header files included with \fB#include <\fR\fIfile\fR\fB>\fR
|
|
are omitted.
|
|
.Ip "\fB\-MF\fR \fIfile\fR" 4
|
|
.IX Item "-MF file"
|
|
When used with \fB\-M\fR or \fB\-MM\fR, specifies a file to write the
|
|
dependencies to. This allows the preprocessor to write the preprocessed
|
|
file to stdout normally. If no \fB\-MF\fR switch is given, \s-1CPP\s0 sends
|
|
the rules to stdout and suppresses normal preprocessed output.
|
|
.Ip "\fB\-MG\fR" 4
|
|
.IX Item "-MG"
|
|
When used with \fB\-M\fR or \fB\-MM\fR, \fB\-MG\fR says to treat missing
|
|
header files as generated files and assume they live in the same
|
|
directory as the source file. It suppresses preprocessed output, as a
|
|
missing header file is ordinarily an error.
|
|
.Sp
|
|
This feature is used in automatic updating of makefiles.
|
|
.Ip "\fB\-MP\fR" 4
|
|
.IX Item "-MP"
|
|
This option instructs \s-1CPP\s0 to add a phony target for each dependency
|
|
other than the main file, causing each to depend on nothing. These
|
|
dummy rules work around errors \f(CW\*(C`make\*(C'\fR gives if you remove header
|
|
files without updating the \f(CW\*(C`Makefile\*(C'\fR to match.
|
|
.Sp
|
|
This is typical output:\-
|
|
.Sp
|
|
.Vb 1
|
|
\& /tmp/test.o: /tmp/test.c /tmp/test.h
|
|
.Ve
|
|
.Vb 1
|
|
\& /tmp/test.h:
|
|
.Ve
|
|
.Ip "\fB\-MQ\fR \fItarget\fR" 4
|
|
.IX Item "-MQ target"
|
|
.PD 0
|
|
.Ip "\fB\-MT\fR \fItarget\fR" 4
|
|
.IX Item "-MT target"
|
|
.PD
|
|
By default \s-1CPP\s0 uses the main file name, including any path, and appends
|
|
the object suffix, normally ``.o'', to it to obtain the name of the
|
|
target for dependency generation. With \fB\-MT\fR you can specify a
|
|
target yourself, overriding the default one.
|
|
.Sp
|
|
If you want multiple targets, you can specify them as a single argument
|
|
to \fB\-MT\fR, or use multiple \fB\-MT\fR options.
|
|
.Sp
|
|
The targets you specify are output in the order they appear on the
|
|
command line. \fB\-MQ\fR is identical to \fB\-MT\fR, except that the
|
|
target name is quoted for Make, but with \fB\-MT\fR it isn't. For
|
|
example, \-MT '$(objpfx)foo.o' gives
|
|
.Sp
|
|
.Vb 1
|
|
\& $(objpfx)foo.o: /tmp/foo.c
|
|
.Ve
|
|
but \-MQ '$(objpfx)foo.o' gives
|
|
.Sp
|
|
.Vb 1
|
|
\& $$(objpfx)foo.o: /tmp/foo.c
|
|
.Ve
|
|
The default target is automatically quoted, as if it were given with
|
|
\&\fB\-MQ\fR.
|
|
.Ip "\fB\-H\fR" 4
|
|
.IX Item "-H"
|
|
Print the name of each header file used, in addition to other normal
|
|
activities.
|
|
.Ip "\fB\-imacros\fR \fIfile\fR" 4
|
|
.IX Item "-imacros file"
|
|
Process \fIfile\fR as input, discarding the resulting output, before
|
|
processing the regular input file. Because the output generated from
|
|
\&\fIfile\fR is discarded, the only effect of \fB\-imacros\fR \fIfile\fR
|
|
is to make the macros defined in \fIfile\fR available for use in the
|
|
main input.
|
|
.Ip "\fB\-include\fR \fIfile\fR" 4
|
|
.IX Item "-include file"
|
|
Process \fIfile\fR as input, and include all the resulting output,
|
|
before processing the regular input file.
|
|
.Ip "\fB\-idirafter\fR \fIdir\fR" 4
|
|
.IX Item "-idirafter dir"
|
|
Add the directory \fIdir\fR to the second include path. The directories
|
|
on the second include path are searched when a header file is not found
|
|
in any of the directories in the main include path (the one that
|
|
\&\fB\-I\fR adds to).
|
|
.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 prefix represents a directory, you should include the
|
|
final \fB/\fR.
|
|
.Ip "\fB\-iwithprefix\fR \fIdir\fR" 4
|
|
.IX Item "-iwithprefix dir"
|
|
Add a directory to the second include path. The directory's name is
|
|
made by concatenating \fIprefix\fR and \fIdir\fR, where \fIprefix\fR was
|
|
specified previously with \fB\-iprefix\fR.
|
|
.Ip "\fB\-isystem\fR \fIdir\fR" 4
|
|
.IX Item "-isystem dir"
|
|
Add a directory to the beginning of the second include path, marking it
|
|
as a system directory, so that it gets the same special treatment as
|
|
is applied to the standard system directories.
|
|
.Ip "\fB\-x c\fR" 4
|
|
.IX Item "-x c"
|
|
.PD 0
|
|
.Ip "\fB\-x c++\fR" 4
|
|
.IX Item "-x c++"
|
|
.Ip "\fB\-x objective-c\fR" 4
|
|
.IX Item "-x objective-c"
|
|
.Ip "\fB\-x assembler-with-cpp\fR" 4
|
|
.IX Item "-x assembler-with-cpp"
|
|
.PD
|
|
Specify the source language: C, \*(C+, Objective-C, or assembly. This has
|
|
nothing to do with standards conformance or extensions; it merely
|
|
selects which base syntax to expect. If you give none of these options,
|
|
cpp will deduce the language from the extension of the source file:
|
|
\&\fB.c\fR, \fB.cc\fR, \fB.m\fR, or \fB.S\fR. Some other common
|
|
extensions for \*(C+ and assembly are also recognized. If cpp does not
|
|
recognize the extension, it will treat the file as C; this is the most
|
|
generic mode.
|
|
.Sp
|
|
\&\fBNote:\fR Previous versions of cpp accepted a \fB\-lang\fR option
|
|
which selected both the language and the standards conformance level.
|
|
This option has been removed, because it conflicts with the \fB\-l\fR
|
|
option.
|
|
.Ip "\fB\-std=\fR\fIstandard\fR" 4
|
|
.IX Item "-std=standard"
|
|
.PD 0
|
|
.Ip "\fB\-ansi\fR" 4
|
|
.IX Item "-ansi"
|
|
.PD
|
|
Specify the standard to which the code should conform. Currently cpp
|
|
only knows about the standards for C; other language standards will be
|
|
added in the future.
|
|
.Sp
|
|
\&\fIstandard\fR
|
|
may be one of:
|
|
.RS 4
|
|
.if n .Ip "\f(CW""iso9899:1990""\fR" 4
|
|
.el .Ip "\f(CWiso9899:1990\fR" 4
|
|
.IX Item "iso9899:1990"
|
|
.PD 0
|
|
.if n .Ip "\f(CW""c89""\fR" 4
|
|
.el .Ip "\f(CWc89\fR" 4
|
|
.IX Item "c89"
|
|
.PD
|
|
The \s-1ISO\s0 C standard from 1990. \fBc89\fR is the customary shorthand for
|
|
this version of the standard.
|
|
.Sp
|
|
The \fB\-ansi\fR option is equivalent to \fB\-std=c89\fR.
|
|
.if n .Ip "\f(CW""iso9899:199409""\fR" 4
|
|
.el .Ip "\f(CWiso9899:199409\fR" 4
|
|
.IX Item "iso9899:199409"
|
|
The 1990 C standard, as amended in 1994.
|
|
.if n .Ip "\f(CW""iso9899:1999""\fR" 4
|
|
.el .Ip "\f(CWiso9899:1999\fR" 4
|
|
.IX Item "iso9899:1999"
|
|
.PD 0
|
|
.if n .Ip "\f(CW""c99""\fR" 4
|
|
.el .Ip "\f(CWc99\fR" 4
|
|
.IX Item "c99"
|
|
.if n .Ip "\f(CW""iso9899:199x""\fR" 4
|
|
.el .Ip "\f(CWiso9899:199x\fR" 4
|
|
.IX Item "iso9899:199x"
|
|
.if n .Ip "\f(CW""c9x""\fR" 4
|
|
.el .Ip "\f(CWc9x\fR" 4
|
|
.IX Item "c9x"
|
|
.PD
|
|
The revised \s-1ISO\s0 C standard, published in December 1999. Before
|
|
publication, this was known as C9X.
|
|
.if n .Ip "\f(CW""gnu89""\fR" 4
|
|
.el .Ip "\f(CWgnu89\fR" 4
|
|
.IX Item "gnu89"
|
|
The 1990 C standard plus \s-1GNU\s0 extensions. This is the default.
|
|
.if n .Ip "\f(CW""gnu99""\fR" 4
|
|
.el .Ip "\f(CWgnu99\fR" 4
|
|
.IX Item "gnu99"
|
|
.PD 0
|
|
.if n .Ip "\f(CW""gnu9x""\fR" 4
|
|
.el .Ip "\f(CWgnu9x\fR" 4
|
|
.IX Item "gnu9x"
|
|
.PD
|
|
The 1999 C standard plus \s-1GNU\s0 extensions.
|
|
.RE
|
|
.RS 4
|
|
.RE
|
|
.Ip "\fB\-ftabstop=NUMBER\fR" 4
|
|
.IX Item "-ftabstop=NUMBER"
|
|
Set the distance between tab stops. This helps the preprocessor
|
|
report correct column numbers in warnings or errors, even if tabs appear
|
|
on the line. Values less than 1 or greater than 100 are ignored. The
|
|
default is 8.
|
|
.Ip "\fB\-$\fR" 4
|
|
.IX Item "-$"
|
|
Forbid the use of \fB$\fR in identifiers. The C standard allows
|
|
implementations to define extra characters that can appear in
|
|
identifiers. By default the \s-1GNU\s0 C preprocessor permits \fB$\fR, a
|
|
common extension.
|
|
.SH "SEE ALSO"
|
|
.IX Header "SEE ALSO"
|
|
\&\fIgcc\fR\|(1), \fIas\fR\|(1), \fIld\fR\|(1), and the Info entries for \fIcpp\fR, \fIgcc\fR, and
|
|
\&\fIbinutils\fR.
|
|
.SH "COPYRIGHT"
|
|
.IX Header "COPYRIGHT"
|
|
Copyright (c) 1987, 1989, 1991, 1992, 1993, 1994, 1995, 1996,
|
|
1997, 1998, 1999, 2000, 2001
|
|
Free Software Foundation, Inc.
|
|
.PP
|
|
Permission is granted to make and distribute verbatim copies of
|
|
this manual provided the copyright notice and this permission notice
|
|
are preserved on all copies.
|
|
.PP
|
|
Permission is granted to copy and distribute modified versions of this
|
|
manual under the conditions for verbatim copying, provided also that
|
|
the entire resulting derived work is distributed under the terms of a
|
|
permission notice identical to this one.
|
|
.PP
|
|
Permission is granted to copy and distribute translations of this manual
|
|
into another language, under the above conditions for modified versions.
|