NAME
cpp - The C Preprocessor
SYNOPSIS
cpp [
-Dmacro[=
defn]...] [
-Umacro]
[
-Idir...] [
-iquotedir...]
[
-iremapsrc:
dst]
[
-Wwarn...]
[
-M|
-MM] [
-MG] [
-MF filename]
[
-MP] [
-MQ target...]
[
-MT target...]
[
-P] [
-fno-working-directory]
[
-x language] [
-std=standard]
infile outfile
Only the most useful options are listed here; see below for the remainder.
DESCRIPTION
The C preprocessor, often known as
cpp, is a
macro processor that
is used automatically by the C compiler to transform your program before
compilation. It is called a macro processor because it allows you to define
macros, which are brief abbreviations for longer constructs.
The C preprocessor is intended to be used only with C, C++, and Objective-C
source code. In the past, it has been abused as a general text processor. It
will choke on input which does not obey C's lexical rules. For example,
apostrophes will be interpreted as the beginning of character constants, and
cause errors. Also, you cannot rely on it preserving characteristics of the
input which are not significant to C-family languages. If a Makefile is
preprocessed, all the hard tabs will be removed, and the Makefile will not
work.
Having said that, you can often get away with using cpp on things which are not
C. Other Algol-ish programming languages are often safe (Pascal, Ada, etc.) So
is assembly, with caution.
-traditional-cpp mode preserves more white
space, and is otherwise more permissive. Many of the problems can be avoided
by writing C or C++ style comments instead of native language comments, and
keeping macros simple.
Wherever possible, you should use a preprocessor geared to the language you are
writing in. Modern versions of the GNU assembler have macro facilities. Most
high level programming languages have their own conditional compilation and
inclusion mechanism. If all else fails, try a true general text processor,
such as GNU M4.
C preprocessors vary in some details. This manual discusses the GNU C
preprocessor, which provides a small superset of the features of ISO Standard
C. In its default mode, the GNU C preprocessor does not do a few things
required by the standard. These are features which are rarely, if ever, used,
and may cause surprising changes to the meaning of a program which does not
expect them. To get strict ISO Standard C, you should use the
-std=c90,
-std=c99 or
-std=c11 options, depending on which version of the
standard you want. To get all the mandatory diagnostics, you must also use
-pedantic.
This manual describes the behavior of the ISO preprocessor. To minimize
gratuitous differences, where the ISO preprocessor's behavior does not
conflict with traditional semantics, the traditional preprocessor should
behave the same way. The various differences that do exist are detailed in the
section
Traditional Mode.
For clarity, unless noted otherwise, references to
CPP in this manual
refer to GNU CPP.
OPTIONS
The C preprocessor expects two file names as arguments,
infile and
outfile. The preprocessor reads
infile together with any other
files it specifies with
#include. All the output generated by the
combined input files is written in
outfile.
Either
infile or
outfile may be
-, which as
infile
means to read from standard input and as
outfile means to write to
standard output. Also, if either file is omitted, it means the same as if
- had been specified for that file.
Unless otherwise noted, or the option ends in
=, all options which take
an argument may have that argument appear either immediately after the option,
or with a space between option and argument:
-Ifoo and
-I foo
have the same effect.
Many options have multi-letter names; therefore multiple single-letter options
may
not be grouped:
-dM is very different from
-d -M.
- -D name
- Predefine name as a macro, with definition 1.
- -D name=definition
- The contents of definition are tokenized and
processed as if they appeared during translation phase three in a
#define directive. In particular, the definition will be truncated
by embedded newline characters.
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 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,
-D'name(args...)=definition'
works.
-D and -U 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.
- -U name
- Cancel any previous definition of name, either built
in or provided with a -D option.
- -undef
- Do not predefine any system-specific or GCC-specific
macros. The standard predefined macros remain defined.
- -I dir
- Add the directory dir to the list of directories to
be searched for header files.
Directories named by -I are searched before the standard system
include directories. If the directory dir is a standard system
include directory, the option is ignored to ensure that the default search
order for system directories and the special treatment of system headers
are not defeated . If dir begins with "=", then the
"=" will be replaced by the sysroot prefix; see --sysroot
and -isysroot.
- -o file
- Write output to file. This is the same as specifying
file as the second non-option argument to cpp. gcc
has a different interpretation of a second non-option argument, so you
must use -o to specify the output file.
- -Wall
- Turns on all optional warnings which are desirable for
normal code. At present this is -Wcomment, -Wtrigraphs,
-Wmultichar and a warning about integer promotion causing a change
of sign in "#if" expressions. Note that many of the
preprocessor's warnings are on by default and have no options to control
them.
- -Wcomment
- -Wcomments
- Warn whenever a comment-start sequence /* appears in
a /* comment, or whenever a backslash-newline appears in a
// comment. (Both forms have the same effect.)
- -Wtrigraphs
- Most trigraphs in comments cannot affect the meaning of the
program. However, a trigraph that would form an escaped newline (
??/ at the end of a line) can, by changing where the comment begins
or ends. Therefore, only trigraphs that would form escaped newlines
produce warnings inside a comment.
This option is implied by -Wall. If -Wall is not given, this
option is still enabled unless trigraphs are enabled. To get trigraph
conversion without warnings, but get the other -Wall warnings, use
-trigraphs -Wall -Wno-trigraphs.
- -Wtraditional
- Warn about certain constructs that behave differently in
traditional and ISO C. Also warn about ISO C constructs that have no
traditional C equivalent, and problematic constructs which should be
avoided.
- -Wundef
- Warn whenever an identifier which is not a macro is
encountered in an #if directive, outside of defined. Such
identifiers are replaced with zero.
- -Wunused-macros
- Warn about macros defined in the main file that are unused.
A macro is used if it is expanded or tested for existence at least
once. The preprocessor will also warn if the macro has not been used at
the time it is redefined or undefined.
Built-in macros, macros defined on the command line, and macros defined in
include files are not warned about.
Note: If a macro is actually used, but only used in skipped
conditional blocks, then CPP will report it as unused. To avoid the
warning in such a case, you might improve the scope of the macro's
definition by, for example, moving it into the first skipped block.
Alternatively, you could provide a dummy use with something like:
#if defined the_macro_causing_the_warning
#endif
- -Wendif-labels
- Warn whenever an #else or an #endif are
followed by text. This usually happens in code of the form
#if FOO
...
#else FOO
...
#endif FOO
The second and third "FOO" should be in comments, but often are
not in older programs. This warning is on by default.
- -Werror
- Make all warnings into hard errors. Source code which
triggers warnings will be rejected.
- -Wsystem-headers
- Issue warnings for code in system headers. These are
normally unhelpful in finding bugs in your own code, therefore suppressed.
If you are responsible for the system library, you may want to see
them.
- -w
- Suppress all warnings, including those which GNU CPP issues
by default.
- -pedantic
- Issue all the mandatory diagnostics listed in the C
standard. Some of them are left out by default, since they trigger
frequently on harmless code.
- -pedantic-errors
- Issue all the mandatory diagnostics, and make all mandatory
diagnostics into errors. This includes mandatory diagnostics that GCC
issues without -pedantic but treats as warnings.
- -M
- Instead of outputting the result of preprocessing, output a
rule suitable for make describing the dependencies of the main
source file. The preprocessor outputs one make rule containing the
object file name for that source file, a colon, and the names of all the
included files, including those coming from -include or
-imacros command-line options.
Unless specified explicitly (with -MT or -MQ), the object file
name consists of the name of the source file with any suffix replaced with
object file suffix and with any leading directory parts removed. If there
are many included files then the rule is split into several lines using
\-newline. The rule has no commands.
This option does not suppress the preprocessor's debug output, such as
-dM. To avoid mixing such debug output with the dependency rules
you should explicitly specify the dependency output file with -MF,
or use an environment variable like DEPENDENCIES_OUTPUT. Debug
output will still be sent to the regular output stream as normal.
Passing -M to the driver implies -E, and suppresses warnings
with an implicit -w.
- -MM
- Like -M but do not mention header files that are
found in system header directories, nor header files that are included,
directly or indirectly, from such a header.
This implies that the choice of angle brackets or double quotes in an
#include directive does not in itself determine whether that header
will appear in -MM dependency output. This is a slight change in
semantics from GCC versions 3.0 and earlier.
- -MF file
- When used with -M or -MM, specifies a file to
write the dependencies to. If no -MF switch is given the
preprocessor sends the rules to the same place it would have sent
preprocessed output.
When used with the driver options -MD or -MMD, -MF
overrides the default dependency output file.
- -MG
- In conjunction with an option such as -M requesting
dependency generation, -MG assumes missing header files are
generated files and adds them to the dependency list without raising an
error. The dependency filename is taken directly from the
"#include" directive without prepending any path. -MG
also suppresses preprocessed output, as a missing header file renders this
useless.
This feature is used in automatic updating of makefiles.
- -MP
- This option instructs CPP 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 make gives if you remove
header files without updating the Makefile to match.
This is typical output:
test.o: test.c test.h
test.h:
- -MT target
- Change the target of the rule emitted by dependency
generation. By default CPP takes the name of the main input file, deletes
any directory components and any file suffix such as .c, and
appends the platform's usual object suffix. The result is the target.
An -MT option will set the target to be exactly the string you
specify. If you want multiple targets, you can specify them as a single
argument to -MT, or use multiple -MT options.
For example, -MT '$(objpfx)foo.o' might give
$(objpfx)foo.o: foo.c
- -MQ target
- Same as -MT, but it quotes any characters which are
special to Make. -MQ '$(objpfx)foo.o' gives
$$(objpfx)foo.o: foo.c
The default target is automatically quoted, as if it were given with
-MQ.
- -MD
- -MD is equivalent to -M -MF file,
except that -E is not implied. The driver determines file
based on whether an -o option is given. If it is, the driver uses
its argument but with a suffix of .d, otherwise it takes the name
of the input file, removes any directory components and suffix, and
applies a .d suffix.
If -MD is used in conjunction with -E, any -o switch is
understood to specify the dependency output file, but if used without
-E, each -o is understood to specify a target object file.
Since -E is not implied, -MD can be used to generate a
dependency output file as a side-effect of the compilation process.
- -MMD
- Like -MD except mention only user header files, not
system header files.
- -x c
- -x c++
- -x objective-c
- -x assembler-with-cpp
- 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: .c, .cc, .m, or .S. 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.
Note: Previous versions of cpp accepted a -lang option which
selected both the language and the standards conformance level. This
option has been removed, because it conflicts with the -l
option.
- -std=standard
- -ansi
- Specify the standard to which the code should conform.
Currently CPP knows about C and C++ standards; others may be added in the
future.
standard may be one of:
- "c90"
- "c89"
- "iso9899:1990"
- The ISO C standard from 1990. c90 is the customary
shorthand for this version of the standard.
The -ansi option is equivalent to -std=c90.
- "iso9899:199409"
- The 1990 C standard, as amended in 1994.
- "iso9899:1999"
- "c99"
- "iso9899:199x"
- "c9x"
- The revised ISO C standard, published in December 1999.
Before publication, this was known as C9X.
- "iso9899:2011"
- "c11"
- "c1x"
- The revised ISO C standard, published in December 2011.
Before publication, this was known as C1X.
- "gnu90"
- "gnu89"
- The 1990 C standard plus GNU extensions. This is the
default.
- "gnu99"
- "gnu9x"
- The 1999 C standard plus GNU extensions.
- "gnu11"
- "gnu1x"
- The 2011 C standard plus GNU extensions.
- "c++98"
- The 1998 ISO C++ standard plus amendments.
- "gnu++98"
- The same as -std=c++98 plus GNU extensions. This is
the default for C++ code.
- -I-
- Split the include path. Any directories specified with
-I options before -I- are searched only for headers
requested with "#include " file""; they
are not searched for "#include < file>". If
additional directories are specified with -I options after the
-I-, those directories are searched for all #include
directives.
In addition, -I- inhibits the use of the directory of the current
file directory as the first search directory for
"#include " file"".
This option has been deprecated.
- -nostdinc
- Do not search the standard system directories for header
files. Only the directories you have specified with -I options (and
the directory of the current file, if appropriate) are searched.
- -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.)
- -include file
- Process file as if "#include
"file"" appeared as the first line of the primary source
file. However, the first directory searched for file is the
preprocessor's working directory instead of the directory
containing the main source file. If not found there, it is searched for in
the remainder of the "#include "..."" search chain as
normal.
If multiple -include options are given, the files are included in the
order they appear on the command line.
- -imacros file
- Exactly like -include, except that any output
produced by scanning file is thrown away. Macros it defines remain
defined. This allows you to acquire all the macros from a header without
also processing its declarations.
All files specified by -imacros are processed before all files
specified by -include.
- -idirafter dir
- Search dir for header files, but do it after
all directories specified with -I and the standard system
directories have been exhausted. dir is treated as a system include
directory. If dir begins with "=", then the "="
will be replaced by the sysroot prefix; see --sysroot and
-isysroot.
- -iprefix prefix
- Specify prefix as the prefix for subsequent
-iwithprefix options. If the prefix represents a directory, you
should include the final /.
- -iwithprefix dir
- -iwithprefixbefore dir
- Append dir to the prefix specified previously with
-iprefix, and add the resulting directory to the include search
path. -iwithprefixbefore puts it in the same place -I would;
-iwithprefix puts it where -idirafter would.
- -isysroot dir
- This option is like the --sysroot option, but
applies only to header files (except for Darwin targets, where it applies
to both header files and libraries). See the --sysroot option for
more information.
- -imultilib dir
- Use dir as a subdirectory of the directory
containing target-specific C++ headers.
- -isystem dir
- Search dir for header files, after all directories
specified by -I 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 dir begins with "=", then the "=" will be
replaced by the sysroot prefix; see --sysroot and
-isysroot.
- -cxx-isystem dir
- Search dir for C++ header files, after all
directories specified by -I 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.
- -iquote dir
- Search dir only for header files requested with
"#include " file""; they are not searched
for "#include < file>", before all directories
specified by -I and before the standard system directories.
If dir begins with "=", then the "=" will be
replaced by the sysroot prefix; see --sysroot and
-isysroot.
- -fdirectives-only
- When preprocessing, handle directives, but do not expand
macros.
The option's behavior depends on the -E and -fpreprocessed
options.
With -E, preprocessing is limited to the handling of directives such
as "#define", "#ifdef", and "#error". Other
preprocessor operations, such as macro expansion and trigraph conversion
are not performed. In addition, the -dD option is implicitly
enabled.
With -fpreprocessed, predefinition of command line and most builtin
macros is disabled. Macros such as "__LINE__", which are
contextually dependent, are handled normally. This enables compilation of
files previously preprocessed with "-E -fdirectives-only".
With both -E and -fpreprocessed, the rules for
-fpreprocessed take precedence. This enables full preprocessing of
files previously preprocessed with "-E -fdirectives-only".
- -iremap src:dst
- Replace the prefix src in __FILE__ with dst
at expansion time. This option can be specified more than once. Processing
stops at the first match.
- -fdollars-in-identifiers
- Accept $ in identifiers.
- -fextended-identifiers
- Accept universal character names in identifiers. This
option is enabled by default for C99 (and later C standard versions) and
C++.
- -fno-canonical-system-headers
- When preprocessing, do not shorten system header paths with
canonicalization.
- -fpreprocessed
- Indicate to the preprocessor that the input file has
already been preprocessed. This suppresses things like macro expansion,
trigraph conversion, escaped newline splicing, and processing of most
directives. The preprocessor still recognizes and removes comments, so
that you can pass a file preprocessed with -C to the compiler
without problems. In this mode the integrated preprocessor is little more
than a tokenizer for the front ends.
-fpreprocessed is implicit if the input file has one of the
extensions .i, .ii or .mi. These are the extensions
that GCC uses for preprocessed files created by -save-temps.
- -ftabstop=width
- 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. If the value is less than 1 or greater than 100,
the option is ignored. The default is 8.
- -fdebug-cpp
- This option is only useful for debugging GCC. When used
with -E, dumps debugging information about location maps. Every
token in the output is preceded by the dump of the map its location
belongs to. The dump of the map holding the location of a token would be:
{"P":F</file/path>;"F":F</includer/path>;"L":<line_num>;"C":<col_num>;"S":<system_header_p>;"M":<map_address>;"E":<macro_expansion_p>,"loc":<location>}
When used without -E, this option has no effect.
- -ftrack-macro-expansion[=level]
- Track locations of tokens across macro expansions. This
allows the compiler to emit diagnostic about the current macro expansion
stack when a compilation error occurs in a macro expansion. Using this
option makes the preprocessor and the compiler consume more memory. The
level parameter can be used to choose the level of precision of
token location tracking thus decreasing the memory consumption if
necessary. Value 0 of level de-activates this option just as
if no -ftrack-macro-expansion was present on the command line.
Value 1 tracks tokens locations in a degraded mode for the sake of
minimal memory overhead. In this mode all tokens resulting from the
expansion of an argument of a function-like macro have the same location.
Value 2 tracks tokens locations completely. This value is the most
memory hungry. When this option is given no argument, the default
parameter value is 2.
Note that "-ftrack-macro-expansion=2" is activated by
default.
- -fexec-charset=charset
- Set the execution character set, used for string and
character constants. The default is UTF-8. charset can be any
encoding supported by the system's "iconv" library routine.
- -fwide-exec-charset=charset
- Set the wide execution character set, used for wide string
and character constants. The default is UTF-32 or UTF-16, whichever
corresponds to the width of "wchar_t". As with
-fexec-charset, charset can be any encoding supported by the
system's "iconv" library routine; however, you will have
problems with encodings that do not fit exactly in
"wchar_t".
- -finput-charset=charset
- Set the input character set, used for translation from the
character set of the input file to the source character set used by GCC.
If the locale does not specify, or GCC cannot get this information from
the locale, the default is UTF-8. This can be overridden by either the
locale or this command-line option. Currently the command-line option
takes precedence if there's a conflict. charset can be any encoding
supported by the system's "iconv" library routine.
- -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. GCC will use this directory, when it's
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 -fno-working-directory. If the
-P flag is present in the command line, this option has no effect,
since no "#line" directives are emitted whatsoever.
- -fno-show-column
- Do not print column numbers in diagnostics. This may be
necessary if diagnostics are being scanned by a program that does not
understand the column numbers, such as dejagnu.
- -A predicate=answer
- Make an assertion with the predicate predicate and
answer answer. This form is preferred to the older form -A
predicate(answer), which is still supported,
because it does not use shell special characters.
- -A -predicate=answer
- Cancel an assertion with the predicate predicate and
answer answer.
- -dCHARS
- CHARS is a sequence of one or more of the following
characters, and must not be preceded by a space. Other characters are
interpreted by the compiler proper, or reserved for future versions of
GCC, and so are silently ignored. If you specify characters whose behavior
conflicts, the result is undefined.
- M
- Instead of the normal output, generate a list of
#define 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 foo.h, the command
touch foo.h; cpp -dM foo.h
will show all the predefined macros.
If you use -dM without the -E option, -dM is
interpreted as a synonym for -fdump-rtl-mach.
- D
- Like M except in two respects: it does not
include the predefined macros, and it outputs both the
#define directives and the result of preprocessing. Both kinds of
output go to the standard output file.
- N
- Like D, but emit only the macro names, not their
expansions.
- I
- Output #include directives in addition to the result
of preprocessing.
- U
- Like D 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 #undef
directives are also output for macros tested but undefined at the
time.
- -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.
- -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.
You should be prepared for side effects when using -C; 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 #.
- -CC
- Do not discard comments, including during macro expansion.
This is like -C, except that comments contained within macros are
also passed through to the output file where the macro is expanded.
In addition to the side-effects of the -C option, the -CC
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 -CC option is generally used to support lint comments.
- -traditional-cpp
- Try to imitate the behavior of old-fashioned C
preprocessors, as opposed to ISO C preprocessors.
- -trigraphs
- Process trigraph sequences.
- -remap
- Enable special code to work around file systems which only
permit very short file names, such as MS-DOS.
- --help
- --target-help
- Print text describing all the command-line options instead
of preprocessing anything.
- -v
- Verbose mode. Print out GNU CPP's version number at the
beginning of execution, and report the final form of the include
path.
- -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
#include stack it is. Precompiled header files are also printed,
even if they are found to be invalid; an invalid precompiled header file
is printed with ...x and a valid one with ...! .
- -version
- --version
- Print out GNU CPP's version number. With one dash, proceed
to preprocess as normal. With two dashes, exit immediately.
ENVIRONMENT
This section describes the environment variables that affect how CPP operates.
You can use them to specify directories or prefixes to use when searching for
include files, or to control dependency output.
Note that you can also specify places to search using options such as
-I,
and control dependency output with options like
-M. These take
precedence over environment variables, which in turn take precedence over the
configuration of GCC.
- CPATH
- C_INCLUDE_PATH
- CPLUS_INCLUDE_PATH
- OBJC_INCLUDE_PATH
- Each variable's value is a list of directories separated by
a special character, much like PATH, in which to look for header
files. The special character, "PATH_SEPARATOR", is
target-dependent and determined at GCC build time. For Microsoft
Windows-based targets it is a semicolon, and for almost all other targets
it is a colon.
CPATH specifies a list of directories to be searched as if specified
with -I, but after any paths given with -I options on the
command line. This environment variable is used regardless of which
language is being preprocessed.
The remaining environment variables apply only when preprocessing the
particular language indicated. Each specifies a list of directories to be
searched as if specified with -isystem, but after any paths given
with -isystem options on the command line.
In all these variables, an empty element instructs the compiler to search
its current working directory. Empty elements can appear at the beginning
or end of a path. For instance, if the value of CPATH is
":/special/include", that has the same effect as
-I. -I/special/include.
- DEPENDENCIES_OUTPUT
- If this variable is set, its value specifies how to output
dependencies for Make based on the non-system header files processed by
the compiler. System header files are ignored in the dependency output.
The value of DEPENDENCIES_OUTPUT can be just a file name, in which
case the Make rules are written to that file, guessing the target name
from the source file name. Or the value can have the form file
target, in which case the rules are written to file
file using target as the target name.
In other words, this environment variable is equivalent to combining the
options -MM and -MF, with an optional -MT switch
too.
- SUNPRO_DEPENDENCIES
- This variable is the same as DEPENDENCIES_OUTPUT
(see above), except that system header files are not ignored, so it
implies -M rather than -MM. However, the dependence on the
main input file is omitted.
- CPP_RESTRICTED
- If this variable is defined, cpp will skip any include file
which is not a regular file, and will continue searching for the requested
name (this is always done if the found file is a directory).
SEE ALSO
gpl(7),
gfdl(7),
fsf-funding(7),
gcc(1),
as(1),
ld(1), and the Info entries for
cpp,
gcc,
and
binutils.
COPYRIGHT
Copyright (c) 1987-2015 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document under the
terms of the GNU Free Documentation License, Version 1.3 or any later version
published by the Free Software Foundation. A copy of the license is included
in the man page
gfdl(7). This manual contains no Invariant Sections.
The Front-Cover Texts are (a) (see below), and the Back-Cover Texts are (b)
(see below).
(a) The FSF's Front-Cover Text is:
A GNU Manual
(b) The FSF's Back-Cover Text is:
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.