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138.\" ======================================================================
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129.\" ======================================================================== |
130.\" 131.IX Title "CPP 1"
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141.TH CPP 1 "gcc-3.2.2" "2003-02-05" "GNU"
142.UC
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132.TH CPP 1 "2006-03-06" "gcc-3.4.6" "GNU" |
133.SH "NAME" 134cpp \- The C Preprocessor 135.SH "SYNOPSIS" 136.IX Header "SYNOPSIS" 137cpp [\fB\-D\fR\fImacro\fR[=\fIdefn\fR]...] [\fB\-U\fR\fImacro\fR] 138 [\fB\-I\fR\fIdir\fR...] [\fB\-W\fR\fIwarn\fR...] 139 [\fB\-M\fR|\fB\-MM\fR] [\fB\-MG\fR] [\fB\-MF\fR \fIfilename\fR]
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150 [\fB\-MP\fR] [\fB\-MQ\fR \fItarget\fR...] [\fB\-MT\fR \fItarget\fR...]
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140 [\fB\-MP\fR] [\fB\-MQ\fR \fItarget\fR...] 141 [\fB\-MT\fR \fItarget\fR...] 142 [\fB\-P\fR] [\fB\-fno\-working\-directory\fR] |
143 [\fB\-x\fR \fIlanguage\fR] [\fB\-std=\fR\fIstandard\fR] 144 \fIinfile\fR \fIoutfile\fR 145.PP 146Only the most useful options are listed here; see below for the remainder. 147.SH "DESCRIPTION" 148.IX Header "DESCRIPTION" 149The C preprocessor, often known as \fIcpp\fR, is a \fImacro processor\fR 150that is used automatically by the C compiler to transform your program 151before compilation. It is called a macro processor because it allows 152you to define \fImacros\fR, which are brief abbreviations for longer 153constructs. 154.PP 155The C preprocessor is intended to be used only with C, \*(C+, and 156Objective-C source code. In the past, it has been abused as a general 157text processor. It will choke on input which does not obey C's lexical 158rules. For example, apostrophes will be interpreted as the beginning of 159character constants, and cause errors. Also, you cannot rely on it 160preserving characteristics of the input which are not significant to
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169C-family languages. If a Makefile is preprocessed, all the hard tabs
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161C\-family languages. If a Makefile is preprocessed, all the hard tabs |
162will be removed, and the Makefile will not work. 163.PP 164Having said that, you can often get away with using cpp on things which 165are not C. Other Algol-ish programming languages are often safe
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174(Pascal, Ada, etc.) So is assembly, with caution. \fB\-traditional\fR
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166(Pascal, Ada, etc.) So is assembly, with caution. \fB\-traditional\-cpp\fR |
167mode preserves more white space, and is otherwise more permissive. Many 168of the problems can be avoided by writing C or \*(C+ style comments 169instead of native language comments, and keeping macros simple. 170.PP 171Wherever possible, you should use a preprocessor geared to the language 172you are writing in. Modern versions of the \s-1GNU\s0 assembler have macro 173facilities. Most high level programming languages have their own 174conditional compilation and inclusion mechanism. If all else fails, 175try a true general text processor, such as \s-1GNU\s0 M4. 176.PP 177C preprocessors vary in some details. This manual discusses the \s-1GNU\s0 C 178preprocessor, which provides a small superset of the features of \s-1ISO\s0 179Standard C. In its default mode, the \s-1GNU\s0 C preprocessor does not do a 180few things required by the standard. These are features which are 181rarely, if ever, used, and may cause surprising changes to the meaning 182of a program which does not expect them. To get strict \s-1ISO\s0 Standard C, 183you should use the \fB\-std=c89\fR or \fB\-std=c99\fR options, depending 184on which version of the standard you want. To get all the mandatory 185diagnostics, you must also use \fB\-pedantic\fR.
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186.PP 187This manual describes the behavior of the \s-1ISO\s0 preprocessor. To 188minimize gratuitous differences, where the \s-1ISO\s0 preprocessor's 189behavior does not conflict with traditional semantics, the 190traditional preprocessor should behave the same way. The various 191differences that do exist are detailed in the section \fBTraditional 192Mode\fR. 193.PP 194For clarity, unless noted otherwise, references to \fB\s-1CPP\s0\fR in this 195manual refer to \s-1GNU\s0 \s-1CPP\s0. |
196.SH "OPTIONS" 197.IX Header "OPTIONS" 198The C preprocessor expects two file names as arguments, \fIinfile\fR and 199\&\fIoutfile\fR. The preprocessor reads \fIinfile\fR together with any 200other files it specifies with \fB#include\fR. All the output generated 201by the combined input files is written in \fIoutfile\fR. 202.PP
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201Either \fIinfile\fR or \fIoutfile\fR may be \fB-\fR, which as
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203Either \fIinfile\fR or \fIoutfile\fR may be \fB\-\fR, which as |
204\&\fIinfile\fR means to read from standard input and as \fIoutfile\fR 205means to write to standard output. Also, if either file is omitted, it
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204means the same as if \fB-\fR had been specified for that file.
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206means the same as if \fB\-\fR had been specified for that file. |
207.PP 208Unless otherwise noted, or the option ends in \fB=\fR, all options 209which take an argument may have that argument appear either immediately 210after the option, or with a space between option and argument: 211\&\fB\-Ifoo\fR and \fB\-I foo\fR have the same effect. 212.PP 213Many options have multi-letter names; therefore multiple single-letter 214options may \fInot\fR be grouped: \fB\-dM\fR is very different from 215\&\fB\-d\ \-M\fR.
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214.Ip "\fB\-D\fR \fIname\fR" 4
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216.IP "\fB\-D\fR \fIname\fR" 4 |
217.IX Item "-D name"
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216Predefine \fIname\fR as a macro, with definition \f(CW\*(C`1\*(C'\fR.
217.Ip "\fB\-D\fR \fIname\fR\fB=\fR\fIdefinition\fR" 4
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218Predefine \fIname\fR as a macro, with definition \f(CW1\fR. 219.IP "\fB\-D\fR \fIname\fR\fB=\fR\fIdefinition\fR" 4 |
220.IX Item "-D name=definition" 221Predefine \fIname\fR as a macro, with definition \fIdefinition\fR.
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220There are no restrictions on the contents of \fIdefinition\fR, but if
221you are invoking the preprocessor from a shell or shell-like program you
222may need to use the shell's quoting syntax to protect characters such as
223spaces that have a meaning in the shell syntax.
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222The contents of \fIdefinition\fR are tokenized and processed as if 223they appeared during translation phase three in a \fB#define\fR 224directive. In particular, the definition will be truncated by 225embedded newline characters. |
226.Sp
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227If you are invoking the preprocessor from a shell or shell-like 228program you may need to use the shell's quoting syntax to protect 229characters such as spaces that have a meaning in the shell syntax. 230.Sp |
231If you wish to define a function-like macro on the command line, write 232its argument list with surrounding parentheses before the equals sign 233(if any). Parentheses are meaningful to most shells, so you will need 234to quote the option. With \fBsh\fR and \fBcsh\fR, 235\&\fB\-D'\fR\fIname\fR\fB(\fR\fIargs...\fR\fB)=\fR\fIdefinition\fR\fB'\fR works. 236.Sp 237\&\fB\-D\fR and \fB\-U\fR options are processed in the order they 238are given on the command line. All \fB\-imacros\fR \fIfile\fR and 239\&\fB\-include\fR \fIfile\fR options are processed after all 240\&\fB\-D\fR and \fB\-U\fR options.
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235.Ip "\fB\-U\fR \fIname\fR" 4
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241.IP "\fB\-U\fR \fIname\fR" 4 |
242.IX Item "-U name" 243Cancel any previous definition of \fIname\fR, either built in or 244provided with a \fB\-D\fR option.
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239.Ip "\fB\-undef\fR" 4
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245.IP "\fB\-undef\fR" 4 |
246.IX Item "-undef"
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241Do not predefine any system-specific macros. The common predefined
242macros remain defined.
243.Ip "\fB\-I\fR \fIdir\fR" 4
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247Do not predefine any system-specific or GCC-specific macros. The 248standard predefined macros remain defined. 249.IP "\fB\-I\fR \fIdir\fR" 4 |
250.IX Item "-I dir" 251Add the directory \fIdir\fR to the list of directories to be searched 252for header files. 253.Sp 254Directories named by \fB\-I\fR are searched before the standard
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249system include directories.
250.Sp
251It is dangerous to specify a standard system include directory in an
252\&\fB\-I\fR option. This defeats the special treatment of system
253headers
254\&. It can also defeat the repairs to buggy system headers which \s-1GCC\s0
255makes when it is installed.
256.Ip "\fB\-o\fR \fIfile\fR" 4
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255system include directories. If the directory \fIdir\fR is a standard 256system include directory, the option is ignored to ensure that the 257default search order for system directories and the special treatment 258of system headers are not defeated 259\&. 260.IP "\fB\-o\fR \fIfile\fR" 4 |
261.IX Item "-o file" 262Write output to \fIfile\fR. This is the same as specifying \fIfile\fR 263as the second non-option argument to \fBcpp\fR. \fBgcc\fR has a 264different interpretation of a second non-option argument, so you must 265use \fB\-o\fR to specify the output file.
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262.Ip "\fB\-Wall\fR" 4
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266.IP "\fB\-Wall\fR" 4 |
267.IX Item "-Wall"
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264Turns on all optional warnings which are desirable for normal code. At
265present this is \fB\-Wcomment\fR and \fB\-Wtrigraphs\fR. Note that
266many of the preprocessor's warnings are on by default and have no
267options to control them.
268.Ip "\fB\-Wcomment\fR" 4
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268Turns on all optional warnings which are desirable for normal code. 269At present this is \fB\-Wcomment\fR, \fB\-Wtrigraphs\fR, 270\&\fB\-Wmultichar\fR and a warning about integer promotion causing a 271change of sign in \f(CW\*(C`#if\*(C'\fR expressions. Note that many of the 272preprocessor's warnings are on by default and have no options to 273control them. 274.IP "\fB\-Wcomment\fR" 4 |
275.IX Item "-Wcomment" 276.PD 0
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271.Ip "\fB\-Wcomments\fR" 4
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277.IP "\fB\-Wcomments\fR" 4 |
278.IX Item "-Wcomments" 279.PD 280Warn whenever a comment-start sequence \fB/*\fR appears in a \fB/*\fR 281comment, or whenever a backslash-newline appears in a \fB//\fR comment. 282(Both forms have the same effect.)
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277.Ip "\fB\-Wtrigraphs\fR" 4
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283.IP "\fB\-Wtrigraphs\fR" 4 |
284.IX Item "-Wtrigraphs"
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279Warn if any trigraphs are encountered. This option used to take effect
280only if \fB\-trigraphs\fR was also specified, but now works
281independently. Warnings are not given for trigraphs within comments, as
282they do not affect the meaning of the program.
283.Ip "\fB\-Wtraditional\fR" 4
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285@anchor{Wtrigraphs} 286Most trigraphs in comments cannot affect the meaning of the program. 287However, a trigraph that would form an escaped newline (\fB??/\fR at 288the end of a line) can, by changing where the comment begins or ends. 289Therefore, only trigraphs that would form escaped newlines produce 290warnings inside a comment. 291.Sp 292This option is implied by \fB\-Wall\fR. If \fB\-Wall\fR is not 293given, this option is still enabled unless trigraphs are enabled. To 294get trigraph conversion without warnings, but get the other 295\&\fB\-Wall\fR warnings, use \fB\-trigraphs \-Wall \-Wno\-trigraphs\fR. 296.IP "\fB\-Wtraditional\fR" 4 |
297.IX Item "-Wtraditional" 298Warn about certain constructs that behave differently in traditional and 299\&\s-1ISO\s0 C. Also warn about \s-1ISO\s0 C constructs that have no traditional C 300equivalent, and problematic constructs which should be avoided.
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288.Ip "\fB\-Wimport\fR" 4
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301.IP "\fB\-Wimport\fR" 4 |
302.IX Item "-Wimport" 303Warn the first time \fB#import\fR is used.
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291.Ip "\fB\-Wundef\fR" 4
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304.IP "\fB\-Wundef\fR" 4 |
305.IX Item "-Wundef" 306Warn whenever an identifier which is not a macro is encountered in an 307\&\fB#if\fR directive, outside of \fBdefined\fR. Such identifiers are 308replaced with zero.
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296.Ip "\fB\-Werror\fR" 4
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309.IP "\fB\-Wunused\-macros\fR" 4 310.IX Item "-Wunused-macros" 311Warn about macros defined in the main file that are unused. A macro 312is \fIused\fR if it is expanded or tested for existence at least once. 313The preprocessor will also warn if the macro has not been used at the 314time it is redefined or undefined. 315.Sp 316Built-in macros, macros defined on the command line, and macros 317defined in include files are not warned about. 318.Sp 319\&\fBNote:\fR If a macro is actually used, but only used in skipped 320conditional blocks, then \s-1CPP\s0 will report it as unused. To avoid the 321warning in such a case, you might improve the scope of the macro's 322definition by, for example, moving it into the first skipped block. 323Alternatively, you could provide a dummy use with something like: 324.Sp 325.Vb 2 326\& #if defined the_macro_causing_the_warning 327\& #endif 328.Ve 329.IP "\fB\-Wendif\-labels\fR" 4 330.IX Item "-Wendif-labels" 331Warn whenever an \fB#else\fR or an \fB#endif\fR are followed by text. 332This usually happens in code of the form 333.Sp 334.Vb 5 335\& #if FOO 336\& ... 337\& #else FOO 338\& ... 339\& #endif FOO 340.Ve 341.Sp 342The second and third \f(CW\*(C`FOO\*(C'\fR should be in comments, but often are not 343in older programs. This warning is on by default. 344.IP "\fB\-Werror\fR" 4 |
345.IX Item "-Werror" 346Make all warnings into hard errors. Source code which triggers warnings 347will be rejected.
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300.Ip "\fB\-Wsystem-headers\fR" 4
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348.IP "\fB\-Wsystem\-headers\fR" 4 |
349.IX Item "-Wsystem-headers" 350Issue warnings for code in system headers. These are normally unhelpful 351in finding bugs in your own code, therefore suppressed. If you are 352responsible for the system library, you may want to see them.
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305.Ip "\fB\-w\fR" 4
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353.IP "\fB\-w\fR" 4 |
354.IX Item "-w" 355Suppress all warnings, including those which \s-1GNU\s0 \s-1CPP\s0 issues by default.
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308.Ip "\fB\-pedantic\fR" 4
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356.IP "\fB\-pedantic\fR" 4 |
357.IX Item "-pedantic" 358Issue all the mandatory diagnostics listed in the C standard. Some of 359them are left out by default, since they trigger frequently on harmless 360code.
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313.Ip "\fB\-pedantic-errors\fR" 4
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361.IP "\fB\-pedantic\-errors\fR" 4 |
362.IX Item "-pedantic-errors" 363Issue all the mandatory diagnostics, and make all mandatory diagnostics 364into errors. This includes mandatory diagnostics that \s-1GCC\s0 issues 365without \fB\-pedantic\fR but treats as warnings.
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318.Ip "\fB\-M\fR" 4
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366.IP "\fB\-M\fR" 4 |
367.IX Item "-M" 368Instead of outputting the result of preprocessing, output a rule 369suitable for \fBmake\fR describing the dependencies of the main 370source file. The preprocessor outputs one \fBmake\fR rule containing 371the object file name for that source file, a colon, and the names of all 372the included files, including those coming from \fB\-include\fR or 373\&\fB\-imacros\fR command line options. 374.Sp 375Unless specified explicitly (with \fB\-MT\fR or \fB\-MQ\fR), the 376object file name consists of the basename of the source file with any 377suffix replaced with object file suffix. If there are many included 378files then the rule is split into several lines using \fB\e\fR\-newline. 379The rule has no commands. 380.Sp 381This option does not suppress the preprocessor's debug output, such as 382\&\fB\-dM\fR. To avoid mixing such debug output with the dependency 383rules you should explicitly specify the dependency output file with 384\&\fB\-MF\fR, or use an environment variable like 385\&\fB\s-1DEPENDENCIES_OUTPUT\s0\fR. Debug output 386will still be sent to the regular output stream as normal. 387.Sp
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340Passing \fB\-M\fR to the driver implies \fB\-E\fR.
341.Ip "\fB\-MM\fR" 4
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388Passing \fB\-M\fR to the driver implies \fB\-E\fR, and suppresses 389warnings with an implicit \fB\-w\fR. 390.IP "\fB\-MM\fR" 4 |
391.IX Item "-MM" 392Like \fB\-M\fR but do not mention header files that are found in 393system header directories, nor header files that are included, 394directly or indirectly, from such a header. 395.Sp 396This implies that the choice of angle brackets or double quotes in an 397\&\fB#include\fR directive does not in itself determine whether that 398header will appear in \fB\-MM\fR dependency output. This is a 399slight change in semantics from \s-1GCC\s0 versions 3.0 and earlier.
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351.Ip "\fB\-MF\fR \fIfile\fR" 4
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400.Sp 401@anchor{dashMF} 402.IP "\fB\-MF\fR \fIfile\fR" 4 |
403.IX Item "-MF file"
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353@anchor{\-MF}
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404When used with \fB\-M\fR or \fB\-MM\fR, specifies a 405file to write the dependencies to. If no \fB\-MF\fR switch is given 406the preprocessor sends the rules to the same place it would have sent 407preprocessed output. 408.Sp 409When used with the driver options \fB\-MD\fR or \fB\-MMD\fR, 410\&\fB\-MF\fR overrides the default dependency output file.
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361.Ip "\fB\-MG\fR" 4
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411.IP "\fB\-MG\fR" 4 |
412.IX Item "-MG"
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363When used with \fB\-M\fR or \fB\-MM\fR, \fB\-MG\fR says to treat missing
364header files as generated files and assume they live in the same
365directory as the source file. It suppresses preprocessed output, as a
366missing header file is ordinarily an error.
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413In conjunction with an option such as \fB\-M\fR requesting 414dependency generation, \fB\-MG\fR assumes missing header files are 415generated files and adds them to the dependency list without raising 416an error. The dependency filename is taken directly from the 417\&\f(CW\*(C`#include\*(C'\fR directive without prepending any path. \fB\-MG\fR 418also suppresses preprocessed output, as a missing header file renders 419this useless. |
420.Sp 421This feature is used in automatic updating of makefiles.
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369.Ip "\fB\-MP\fR" 4
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422.IP "\fB\-MP\fR" 4 |
423.IX Item "-MP" 424This option instructs \s-1CPP\s0 to add a phony target for each dependency 425other than the main file, causing each to depend on nothing. These 426dummy rules work around errors \fBmake\fR gives if you remove header 427files without updating the \fIMakefile\fR to match. 428.Sp 429This is typical output: 430.Sp 431.Vb 1 432\& test.o: test.c test.h 433.Ve
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434.Sp |
435.Vb 1 436\& test.h: 437.Ve
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384.Ip "\fB\-MT\fR \fItarget\fR" 4
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438.IP "\fB\-MT\fR \fItarget\fR" 4 |
439.IX Item "-MT target" 440Change the target of the rule emitted by dependency generation. By 441default \s-1CPP\s0 takes the name of the main input file, including any path, 442deletes any file suffix such as \fB.c\fR, and appends the platform's 443usual object suffix. The result is the target. 444.Sp 445An \fB\-MT\fR option will set the target to be exactly the string you 446specify. If you want multiple targets, you can specify them as a single 447argument to \fB\-MT\fR, or use multiple \fB\-MT\fR options. 448.Sp 449For example, \fB\-MT\ '$(objpfx)foo.o'\fR might give 450.Sp 451.Vb 1 452\& $(objpfx)foo.o: foo.c 453.Ve
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400.Ip "\fB\-MQ\fR \fItarget\fR" 4
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454.IP "\fB\-MQ\fR \fItarget\fR" 4 |
455.IX Item "-MQ target" 456Same as \fB\-MT\fR, but it quotes any characters which are special to 457Make. \fB\-MQ\ '$(objpfx)foo.o'\fR gives 458.Sp 459.Vb 1 460\& $$(objpfx)foo.o: foo.c 461.Ve
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462.Sp |
463The default target is automatically quoted, as if it were given with 464\&\fB\-MQ\fR.
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410.Ip "\fB\-MD\fR" 4
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465.IP "\fB\-MD\fR" 4 |
466.IX Item "-MD" 467\&\fB\-MD\fR is equivalent to \fB\-M \-MF\fR \fIfile\fR, except that 468\&\fB\-E\fR is not implied. The driver determines \fIfile\fR based on 469whether an \fB\-o\fR option is given. If it is, the driver uses its 470argument but with a suffix of \fI.d\fR, otherwise it take the 471basename of the input file and applies a \fI.d\fR suffix. 472.Sp 473If \fB\-MD\fR is used in conjunction with \fB\-E\fR, any 474\&\fB\-o\fR switch is understood to specify the dependency output file
|
420(but \f(CW@pxref\fR{\-MF}), but if used without \fB\-E\fR, each \fB\-o\fR
|
475(but \f(CW@pxref\fR{dashMF,,\-MF}), but if used without \fB\-E\fR, each \fB\-o\fR |
476is understood to specify a target object file. 477.Sp 478Since \fB\-E\fR is not implied, \fB\-MD\fR can be used to generate 479a dependency output file as a side-effect of the compilation process.
|
425.Ip "\fB\-MMD\fR" 4
|
480.IP "\fB\-MMD\fR" 4 |
481.IX Item "-MMD" 482Like \fB\-MD\fR except mention only user header files, not system 483\&\-header files.
|
429.Ip "\fB\-x c\fR" 4
|
484.IP "\fB\-x c\fR" 4 |
485.IX Item "-x c" 486.PD 0
|
432.Ip "\fB\-x c++\fR" 4
|
487.IP "\fB\-x c++\fR" 4 |
488.IX Item "-x c++"
|
434.Ip "\fB\-x objective-c\fR" 4
|
489.IP "\fB\-x objective-c\fR" 4 |
490.IX Item "-x objective-c"
|
436.Ip "\fB\-x assembler-with-cpp\fR" 4
|
491.IP "\fB\-x assembler-with-cpp\fR" 4 |
492.IX Item "-x assembler-with-cpp" 493.PD
|
439Specify the source language: C, \*(C+, Objective-C, or assembly. This has
|
494Specify the source language: C, \*(C+, Objective\-C, or assembly. This has |
495nothing to do with standards conformance or extensions; it merely 496selects which base syntax to expect. If you give none of these options, 497cpp will deduce the language from the extension of the source file: 498\&\fB.c\fR, \fB.cc\fR, \fB.m\fR, or \fB.S\fR. Some other common 499extensions for \*(C+ and assembly are also recognized. If cpp does not 500recognize the extension, it will treat the file as C; this is the most 501generic mode. 502.Sp 503\&\fBNote:\fR Previous versions of cpp accepted a \fB\-lang\fR option 504which selected both the language and the standards conformance level. 505This option has been removed, because it conflicts with the \fB\-l\fR 506option.
|
452.Ip "\fB\-std=\fR\fIstandard\fR" 4
|
507.IP "\fB\-std=\fR\fIstandard\fR" 4 |
508.IX Item "-std=standard" 509.PD 0
|
455.Ip "\fB\-ansi\fR" 4
|
510.IP "\fB\-ansi\fR" 4 |
511.IX Item "-ansi" 512.PD
|
458Specify the standard to which the code should conform. Currently cpp
459only knows about the standards for C; other language standards will be
460added in the future.
|
513Specify the standard to which the code should conform. Currently \s-1CPP\s0 514knows about C and \*(C+ standards; others may be added in the future. |
515.Sp 516\&\fIstandard\fR 517may be one of: 518.RS 4
|
465.if n .Ip "\f(CW""""iso9899:1990""""\fR" 4
466.el .Ip "\f(CWiso9899:1990\fR" 4
|
519.ie n .IP """iso9899:1990""" 4 520.el .IP "\f(CWiso9899:1990\fR" 4 |
521.IX Item "iso9899:1990" 522.PD 0
|
469.if n .Ip "\f(CW""""c89""""\fR" 4
470.el .Ip "\f(CWc89\fR" 4
|
523.ie n .IP """c89""" 4 524.el .IP "\f(CWc89\fR" 4 |
525.IX Item "c89" 526.PD 527The \s-1ISO\s0 C standard from 1990. \fBc89\fR is the customary shorthand for 528this version of the standard. 529.Sp 530The \fB\-ansi\fR option is equivalent to \fB\-std=c89\fR.
|
477.if n .Ip "\f(CW""""iso9899:199409""""\fR" 4
478.el .Ip "\f(CWiso9899:199409\fR" 4
|
531.ie n .IP """iso9899:199409""" 4 532.el .IP "\f(CWiso9899:199409\fR" 4 |
533.IX Item "iso9899:199409" 534The 1990 C standard, as amended in 1994.
|
481.if n .Ip "\f(CW""""iso9899:1999""""\fR" 4
482.el .Ip "\f(CWiso9899:1999\fR" 4
|
535.ie n .IP """iso9899:1999""" 4 536.el .IP "\f(CWiso9899:1999\fR" 4 |
537.IX Item "iso9899:1999" 538.PD 0
|
485.if n .Ip "\f(CW""""c99""""\fR" 4
486.el .Ip "\f(CWc99\fR" 4
|
539.ie n .IP """c99""" 4 540.el .IP "\f(CWc99\fR" 4 |
541.IX Item "c99"
|
488.if n .Ip "\f(CW""""iso9899:199x""""\fR" 4
489.el .Ip "\f(CWiso9899:199x\fR" 4
|
542.ie n .IP """iso9899:199x""" 4 543.el .IP "\f(CWiso9899:199x\fR" 4 |
544.IX Item "iso9899:199x"
|
491.if n .Ip "\f(CW""""c9x""""\fR" 4
492.el .Ip "\f(CWc9x\fR" 4
|
545.ie n .IP """c9x""" 4 546.el .IP "\f(CWc9x\fR" 4 |
547.IX Item "c9x" 548.PD 549The revised \s-1ISO\s0 C standard, published in December 1999. Before 550publication, this was known as C9X.
|
497.if n .Ip "\f(CW""""gnu89""""\fR" 4
498.el .Ip "\f(CWgnu89\fR" 4
|
551.ie n .IP """gnu89""" 4 552.el .IP "\f(CWgnu89\fR" 4 |
553.IX Item "gnu89" 554The 1990 C standard plus \s-1GNU\s0 extensions. This is the default.
|
501.if n .Ip "\f(CW""""gnu99""""\fR" 4
502.el .Ip "\f(CWgnu99\fR" 4
|
555.ie n .IP """gnu99""" 4 556.el .IP "\f(CWgnu99\fR" 4 |
557.IX Item "gnu99" 558.PD 0
|
505.if n .Ip "\f(CW""""gnu9x""""\fR" 4
506.el .Ip "\f(CWgnu9x\fR" 4
|
559.ie n .IP """gnu9x""" 4 560.el .IP "\f(CWgnu9x\fR" 4 |
561.IX Item "gnu9x" 562.PD 563The 1999 C standard plus \s-1GNU\s0 extensions.
|
564.ie n .IP """c++98""" 4 565.el .IP "\f(CWc++98\fR" 4 566.IX Item "c++98" 567The 1998 \s-1ISO\s0 \*(C+ standard plus amendments. 568.ie n .IP """gnu++98""" 4 569.el .IP "\f(CWgnu++98\fR" 4 570.IX Item "gnu++98" 571The same as \fB\-std=c++98\fR plus \s-1GNU\s0 extensions. This is the 572default for \*(C+ code. |
573.RE 574.RS 4 575.RE
|
513.Ip "\fB\-I-\fR" 4
|
576.IP "\fB\-I\-\fR" 4 |
577.IX Item "-I-" 578Split the include path. Any directories specified with \fB\-I\fR
|
516options before \fB\-I-\fR are searched only for headers requested with
|
579options before \fB\-I\-\fR are searched only for headers requested with |
580\&\f(CW\*(C`#include\ "\f(CIfile\f(CW"\*(C'\fR; they are not searched for 581\&\f(CW\*(C`#include\ <\f(CIfile\f(CW>\*(C'\fR. If additional directories are
|
519specified with \fB\-I\fR options after the \fB\-I-\fR, those
|
582specified with \fB\-I\fR options after the \fB\-I\-\fR, those |
583directories are searched for all \fB#include\fR directives. 584.Sp
|
522In addition, \fB\-I-\fR inhibits the use of the directory of the current
|
585In addition, \fB\-I\-\fR inhibits the use of the directory of the current |
586file directory as the first search directory for \f(CW\*(C`#include\ "\f(CIfile\f(CW"\*(C'\fR.
|
524.Ip "\fB\-nostdinc\fR" 4
|
587.IP "\fB\-nostdinc\fR" 4 |
588.IX Item "-nostdinc" 589Do not search the standard system directories for header files. 590Only the directories you have specified with \fB\-I\fR options 591(and the directory of the current file, if appropriate) are searched.
|
529.Ip "\fB\-nostdinc++\fR" 4
|
592.IP "\fB\-nostdinc++\fR" 4 |
593.IX Item "-nostdinc++" 594Do not search for header files in the \*(C+\-specific standard directories, 595but do still search the other standard directories. (This option is 596used when building the \*(C+ library.)
|
534.Ip "\fB\-include\fR \fIfile\fR" 4
|
597.IP "\fB\-include\fR \fIfile\fR" 4 |
598.IX Item "-include file" 599Process \fIfile\fR as if \f(CW\*(C`#include "file"\*(C'\fR appeared as the first 600line of the primary source file. However, the first directory searched 601for \fIfile\fR is the preprocessor's working directory \fIinstead of\fR 602the directory containing the main source file. If not found there, it 603is searched for in the remainder of the \f(CW\*(C`#include "..."\*(C'\fR search 604chain as normal. 605.Sp 606If multiple \fB\-include\fR options are given, the files are included 607in the order they appear on the command line.
|
545.Ip "\fB\-imacros\fR \fIfile\fR" 4
|
608.IP "\fB\-imacros\fR \fIfile\fR" 4 |
609.IX Item "-imacros file" 610Exactly like \fB\-include\fR, except that any output produced by 611scanning \fIfile\fR is thrown away. Macros it defines remain defined. 612This allows you to acquire all the macros from a header without also 613processing its declarations. 614.Sp 615All files specified by \fB\-imacros\fR are processed before all files 616specified by \fB\-include\fR.
|
554.Ip "\fB\-idirafter\fR \fIdir\fR" 4
|
617.IP "\fB\-idirafter\fR \fIdir\fR" 4 |
618.IX Item "-idirafter dir" 619Search \fIdir\fR for header files, but do it \fIafter\fR all 620directories specified with \fB\-I\fR and the standard system directories 621have been exhausted. \fIdir\fR is treated as a system include directory.
|
559.Ip "\fB\-iprefix\fR \fIprefix\fR" 4
|
622.IP "\fB\-iprefix\fR \fIprefix\fR" 4 |
623.IX Item "-iprefix prefix" 624Specify \fIprefix\fR as the prefix for subsequent \fB\-iwithprefix\fR 625options. If the prefix represents a directory, you should include the 626final \fB/\fR.
|
564.Ip "\fB\-iwithprefix\fR \fIdir\fR" 4
|
627.IP "\fB\-iwithprefix\fR \fIdir\fR" 4 |
628.IX Item "-iwithprefix dir" 629.PD 0
|
567.Ip "\fB\-iwithprefixbefore\fR \fIdir\fR" 4
|
630.IP "\fB\-iwithprefixbefore\fR \fIdir\fR" 4 |
631.IX Item "-iwithprefixbefore dir" 632.PD 633Append \fIdir\fR to the prefix specified previously with 634\&\fB\-iprefix\fR, and add the resulting directory to the include search 635path. \fB\-iwithprefixbefore\fR puts it in the same place \fB\-I\fR 636would; \fB\-iwithprefix\fR puts it where \fB\-idirafter\fR would.
|
574.Sp
575Use of these options is discouraged.
576.Ip "\fB\-isystem\fR \fIdir\fR" 4
|
637.IP "\fB\-isystem\fR \fIdir\fR" 4 |
638.IX Item "-isystem dir" 639Search \fIdir\fR for header files, after all directories specified by 640\&\fB\-I\fR but before the standard system directories. Mark it 641as a system directory, so that it gets the same special treatment as 642is applied to the standard system directories.
|
582.Ip "\fB\-fpreprocessed\fR" 4
|
643.IP "\fB\-fdollars\-in\-identifiers\fR" 4 644.IX Item "-fdollars-in-identifiers" 645@anchor{fdollars\-in\-identifiers} 646Accept \fB$\fR in identifiers. 647.IP "\fB\-fpreprocessed\fR" 4 |
648.IX Item "-fpreprocessed" 649Indicate to the preprocessor that the input file has already been 650preprocessed. This suppresses things like macro expansion, trigraph 651conversion, escaped newline splicing, and processing of most directives. 652The preprocessor still recognizes and removes comments, so that you can 653pass a file preprocessed with \fB\-C\fR to the compiler without 654problems. In this mode the integrated preprocessor is little more than 655a tokenizer for the front ends. 656.Sp 657\&\fB\-fpreprocessed\fR is implicit if the input file has one of the 658extensions \fB.i\fR, \fB.ii\fR or \fB.mi\fR. These are the 659extensions that \s-1GCC\s0 uses for preprocessed files created by
|
595\&\fB\-save-temps\fR.
596.Ip "\fB\-ftabstop=\fR\fIwidth\fR" 4
|
660\&\fB\-save\-temps\fR. 661.IP "\fB\-ftabstop=\fR\fIwidth\fR" 4 |
662.IX Item "-ftabstop=width" 663Set the distance between tab stops. This helps the preprocessor report 664correct column numbers in warnings or errors, even if tabs appear on the 665line. If the value is less than 1 or greater than 100, the option is 666ignored. The default is 8.
|
602.Ip "\fB\-fno-show-column\fR" 4
|
667.IP "\fB\-fexec\-charset=\fR\fIcharset\fR" 4 668.IX Item "-fexec-charset=charset" 669Set the execution character set, used for string and character 670constants. The default is \s-1UTF\-8\s0. \fIcharset\fR can be any encoding 671supported by the system's \f(CW\*(C`iconv\*(C'\fR library routine. 672.IP "\fB\-fwide\-exec\-charset=\fR\fIcharset\fR" 4 673.IX Item "-fwide-exec-charset=charset" 674Set the wide execution character set, used for wide string and 675character constants. The default is \s-1UTF\-32\s0 or \s-1UTF\-16\s0, whichever 676corresponds to the width of \f(CW\*(C`wchar_t\*(C'\fR. As with 677\&\fB\-ftarget\-charset\fR, \fIcharset\fR can be any encoding supported 678by the system's \f(CW\*(C`iconv\*(C'\fR library routine; however, you will have 679problems with encodings that do not fit exactly in \f(CW\*(C`wchar_t\*(C'\fR. 680.IP "\fB\-finput\-charset=\fR\fIcharset\fR" 4 681.IX Item "-finput-charset=charset" 682Set the input character set, used for translation from the character 683set of the input file to the source character set used by \s-1GCC\s0. If the 684locale does not specify, or \s-1GCC\s0 cannot get this information from the 685locale, the default is \s-1UTF\-8\s0. This can be overridden by either the locale 686or this command line option. Currently the command line option takes 687precedence if there's a conflict. \fIcharset\fR can be any encoding 688supported by the system's \f(CW\*(C`iconv\*(C'\fR library routine. 689.IP "\fB\-fworking\-directory\fR" 4 690.IX Item "-fworking-directory" 691Enable generation of linemarkers in the preprocessor output that will 692let the compiler know the current working directory at the time of 693preprocessing. When this option is enabled, the preprocessor will 694emit, after the initial linemarker, a second linemarker with the 695current working directory followed by two slashes. \s-1GCC\s0 will use this 696directory, when it's present in the preprocessed input, as the 697directory emitted as the current working directory in some debugging 698information formats. This option is implicitly enabled if debugging 699information is enabled, but this can be inhibited with the negated 700form \fB\-fno\-working\-directory\fR. If the \fB\-P\fR flag is 701present in the command line, this option has no effect, since no 702\&\f(CW\*(C`#line\*(C'\fR directives are emitted whatsoever. 703.IP "\fB\-fno\-show\-column\fR" 4 |
704.IX Item "-fno-show-column" 705Do not print column numbers in diagnostics. This may be necessary if 706diagnostics are being scanned by a program that does not understand the 707column numbers, such as \fBdejagnu\fR.
|
607.Ip "\fB\-A\fR \fIpredicate\fR\fB=\fR\fIanswer\fR" 4
|
708.IP "\fB\-A\fR \fIpredicate\fR\fB=\fR\fIanswer\fR" 4 |
709.IX Item "-A predicate=answer" 710Make an assertion with the predicate \fIpredicate\fR and answer 711\&\fIanswer\fR. This form is preferred to the older form \fB\-A\fR 712\&\fIpredicate\fR\fB(\fR\fIanswer\fR\fB)\fR, which is still supported, because 713it does not use shell special characters.
|
613.Ip "\fB\-A -\fR\fIpredicate\fR\fB=\fR\fIanswer\fR" 4
|
714.IP "\fB\-A \-\fR\fIpredicate\fR\fB=\fR\fIanswer\fR" 4 |
715.IX Item "-A -predicate=answer" 716Cancel an assertion with the predicate \fIpredicate\fR and answer 717\&\fIanswer\fR.
|
617.Ip "\fB\-A-\fR" 4
618.IX Item "-A-"
619Cancel all predefined assertions and all assertions preceding it on
620the command line. Also, undefine all predefined macros and all
621macros preceding it on the command line. (This is a historical wart and
622may change in the future.)
623.Ip "\fB\-dCHARS\fR" 4
|
718.IP "\fB\-dCHARS\fR" 4 |
719.IX Item "-dCHARS" 720\&\fI\s-1CHARS\s0\fR is a sequence of one or more of the following characters, 721and must not be preceded by a space. Other characters are interpreted 722by the compiler proper, or reserved for future versions of \s-1GCC\s0, and so 723are silently ignored. If you specify characters whose behavior 724conflicts, the result is undefined. 725.RS 4
|
631.Ip "\fBM\fR" 4
|
726.IP "\fBM\fR" 4 |
727.IX Item "M" 728Instead of the normal output, generate a list of \fB#define\fR 729directives for all the macros defined during the execution of the 730preprocessor, including predefined macros. This gives you a way of 731finding out what is predefined in your version of the preprocessor. 732Assuming you have no file \fIfoo.h\fR, the command 733.Sp 734.Vb 1 735\& touch foo.h; cpp -dM foo.h 736.Ve
|
737.Sp |
738will show all the predefined macros.
|
643.Ip "\fBD\fR" 4
|
739.IP "\fBD\fR" 4 |
740.IX Item "D" 741Like \fBM\fR except in two respects: it does \fInot\fR include the 742predefined macros, and it outputs \fIboth\fR the \fB#define\fR 743directives and the result of preprocessing. Both kinds of output go to 744the standard output file.
|
649.Ip "\fBN\fR" 4
|
745.IP "\fBN\fR" 4 |
746.IX Item "N" 747Like \fBD\fR, but emit only the macro names, not their expansions.
|
652.Ip "\fBI\fR" 4
|
748.IP "\fBI\fR" 4 |
749.IX Item "I" 750Output \fB#include\fR directives in addition to the result of 751preprocessing. 752.RE 753.RS 4 754.RE
|
659.Ip "\fB\-P\fR" 4
|
755.IP "\fB\-P\fR" 4 |
756.IX Item "-P" 757Inhibit generation of linemarkers in the output from the preprocessor. 758This might be useful when running the preprocessor on something that is 759not C code, and will be sent to a program which might be confused by the 760linemarkers.
|
665.Ip "\fB\-C\fR" 4
|
761.IP "\fB\-C\fR" 4 |
762.IX Item "-C" 763Do not discard comments. All comments are passed through to the output 764file, except for comments in processed directives, which are deleted 765along with the directive. 766.Sp 767You should be prepared for side effects when using \fB\-C\fR; it 768causes the preprocessor to treat comments as tokens in their own right. 769For example, comments appearing at the start of what would be a 770directive line have the effect of turning that line into an ordinary 771source line, since the first token on the line is no longer a \fB#\fR.
|
676.Ip "\fB\-gcc\fR" 4
677.IX Item "-gcc"
678Define the macros _\|_GNUC_\|_, _\|_GNUC_MINOR_\|_ and
679_\|_GNUC_PATCHLEVEL_\|_. These are defined automatically when you use
680\&\fBgcc \-E\fR; you can turn them off in that case with
681\&\fB\-no-gcc\fR.
682.Ip "\fB\-traditional\fR" 4
683.IX Item "-traditional"
684Try to imitate the behavior of old-fashioned C, as opposed to \s-1ISO\s0
685C.
686.Ip "\fB\-trigraphs\fR" 4
|
772.IP "\fB\-CC\fR" 4 773.IX Item "-CC" 774Do not discard comments, including during macro expansion. This is 775like \fB\-C\fR, except that comments contained within macros are 776also passed through to the output file where the macro is expanded. 777.Sp 778In addition to the side-effects of the \fB\-C\fR option, the 779\&\fB\-CC\fR option causes all \*(C+\-style comments inside a macro 780to be converted to C\-style comments. This is to prevent later use 781of that macro from inadvertently commenting out the remainder of 782the source line. 783.Sp 784The \fB\-CC\fR option is generally used to support lint comments. 785.IP "\fB\-traditional\-cpp\fR" 4 786.IX Item "-traditional-cpp" 787Try to imitate the behavior of old-fashioned C preprocessors, as 788opposed to \s-1ISO\s0 C preprocessors. 789.IP "\fB\-trigraphs\fR" 4 |
790.IX Item "-trigraphs" 791Process trigraph sequences.
|
689.Ip "\fB\-remap\fR" 4
|
792.IP "\fB\-remap\fR" 4 |
793.IX Item "-remap" 794Enable special code to work around file systems which only permit very
|
692short file names, such as \s-1MS-DOS\s0.
693.Ip "\fB\-$\fR" 4
694.IX Item "-$"
695Forbid the use of \fB$\fR in identifiers. The C standard allows
696implementations to define extra characters that can appear in
697identifiers. By default \s-1GNU\s0 \s-1CPP\s0 permits \fB$\fR, a common extension.
698.Ip "\fB\-h\fR" 4
699.IX Item "-h"
|
795short file names, such as \s-1MS\-DOS\s0. 796.IP "\fB\-\-help\fR" 4 797.IX Item "--help" |
798.PD 0
|
701.Ip "\fB\*(--help\fR" 4
702.IX Item "help"
703.Ip "\fB\*(--target-help\fR" 4
704.IX Item "target-help"
|
799.IP "\fB\-\-target\-help\fR" 4 800.IX Item "--target-help" |
801.PD 802Print text describing all the command line options instead of 803preprocessing anything.
|
708.Ip "\fB\-v\fR" 4
|
804.IP "\fB\-v\fR" 4 |
805.IX Item "-v" 806Verbose mode. Print out \s-1GNU\s0 \s-1CPP\s0's version number at the beginning of 807execution, and report the final form of the include path.
|
712.Ip "\fB\-H\fR" 4
|
808.IP "\fB\-H\fR" 4 |
809.IX Item "-H" 810Print the name of each header file used, in addition to other normal 811activities. Each name is indented to show how deep in the
|
716\&\fB#include\fR stack it is.
717.Ip "\fB\-version\fR" 4
|
812\&\fB#include\fR stack it is. Precompiled header files are also 813printed, even if they are found to be invalid; an invalid precompiled 814header file is printed with \fB...x\fR and a valid one with \fB...!\fR . 815.IP "\fB\-version\fR" 4 |
816.IX Item "-version" 817.PD 0
|
720.Ip "\fB\*(--version\fR" 4
721.IX Item "version"
|
818.IP "\fB\-\-version\fR" 4 819.IX Item "--version" |
820.PD 821Print out \s-1GNU\s0 \s-1CPP\s0's version number. With one dash, proceed to 822preprocess as normal. With two dashes, exit immediately. 823.SH "ENVIRONMENT" 824.IX Header "ENVIRONMENT" 825This section describes the environment variables that affect how \s-1CPP\s0 826operates. You can use them to specify directories or prefixes to use 827when searching for include files, or to control dependency output. 828.PP 829Note that you can also specify places to search using options such as 830\&\fB\-I\fR, and control dependency output with options like 831\&\fB\-M\fR. These take precedence over 832environment variables, which in turn take precedence over the 833configuration of \s-1GCC\s0.
|
736.Ip "\fB\s-1CPATH\s0\fR" 4
|
834.IP "\fB\s-1CPATH\s0\fR" 4 |
835.IX Item "CPATH" 836.PD 0
|
739.Ip "\fBC_INCLUDE_PATH\fR" 4
|
837.IP "\fBC_INCLUDE_PATH\fR" 4 |
838.IX Item "C_INCLUDE_PATH"
|
741.Ip "\fB\s-1CPLUS_INCLUDE_PATH\s0\fR" 4
|
839.IP "\fB\s-1CPLUS_INCLUDE_PATH\s0\fR" 4 |
840.IX Item "CPLUS_INCLUDE_PATH"
|
743.Ip "\fB\s-1OBJC_INCLUDE_PATH\s0\fR" 4
|
841.IP "\fB\s-1OBJC_INCLUDE_PATH\s0\fR" 4 |
842.IX Item "OBJC_INCLUDE_PATH" 843.PD 844Each variable's value is a list of directories separated by a special 845character, much like \fB\s-1PATH\s0\fR, in which to look for header files. 846The special character, \f(CW\*(C`PATH_SEPARATOR\*(C'\fR, is target-dependent and
|
749determined at \s-1GCC\s0 build time. For Windows-based targets it is a
|
847determined at \s-1GCC\s0 build time. For Microsoft Windows-based targets it is a |
848semicolon, and for almost all other targets it is a colon. 849.Sp 850\&\fB\s-1CPATH\s0\fR specifies a list of directories to be searched as if 851specified with \fB\-I\fR, but after any paths given with \fB\-I\fR
|
754options on the command line. The environment variable is used
|
852options on the command line. This environment variable is used |
853regardless of which language is being preprocessed. 854.Sp 855The remaining environment variables apply only when preprocessing the 856particular language indicated. Each specifies a list of directories 857to be searched as if specified with \fB\-isystem\fR, but after any 858paths given with \fB\-isystem\fR options on the command line. 859.Sp
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762See also \f(CW@ref\fR{Search Path}.
763.Ip "\fB\s-1DEPENDENCIES_OUTPUT\s0\fR" 4
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860In all these variables, an empty element instructs the compiler to 861search its current working directory. Empty elements can appear at the 862beginning or end of a path. For instance, if the value of 863\&\fB\s-1CPATH\s0\fR is \f(CW\*(C`:/special/include\*(C'\fR, that has the same 864effect as \fB\-I.\ \-I/special/include\fR. 865.IP "\fB\s-1DEPENDENCIES_OUTPUT\s0\fR" 4 |
866.IX Item "DEPENDENCIES_OUTPUT"
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765@anchor{\s-1DEPENDENCIES_OUTPUT\s0}
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867If this variable is set, its value specifies how to output 868dependencies for Make based on the non-system header files processed 869by the compiler. System header files are ignored in the dependency 870output. 871.Sp 872The value of \fB\s-1DEPENDENCIES_OUTPUT\s0\fR can be just a file name, in 873which case the Make rules are written to that file, guessing the target 874name from the source file name. Or the value can have the form 875\&\fIfile\fR\fB \fR\fItarget\fR, in which case the rules are written to 876file \fIfile\fR using \fItarget\fR as the target name. 877.Sp 878In other words, this environment variable is equivalent to combining 879the options \fB\-MM\fR and \fB\-MF\fR, 880with an optional \fB\-MT\fR switch too.
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780.Ip "\fB\s-1SUNPRO_DEPENDENCIES\s0\fR" 4
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881.IP "\fB\s-1SUNPRO_DEPENDENCIES\s0\fR" 4 |
882.IX Item "SUNPRO_DEPENDENCIES"
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782This variable is the same as the environment variable
783\&\fB\s-1DEPENDENCIES_OUTPUT\s0\fR, except that
784system header files are not ignored, so it implies \fB\-M\fR rather
785than \fB\-MM\fR. However, the dependence on the main input file is
786omitted.
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883This variable is the same as \fB\s-1DEPENDENCIES_OUTPUT\s0\fR (see above), 884except that system header files are not ignored, so it implies 885\&\fB\-M\fR rather than \fB\-MM\fR. However, the dependence on the 886main input file is omitted. |
887.SH "SEE ALSO" 888.IX Header "SEE ALSO"
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789\&\fIgpl\fR\|(7), \fIgfdl\fR\|(7), \fIfsf-funding\fR\|(7),
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889\&\fIgpl\fR\|(7), \fIgfdl\fR\|(7), \fIfsf\-funding\fR\|(7), |
890\&\fIgcc\fR\|(1), \fIas\fR\|(1), \fIld\fR\|(1), and the Info entries for \fIcpp\fR, \fIgcc\fR, and 891\&\fIbinutils\fR. 892.SH "COPYRIGHT" 893.IX Header "COPYRIGHT" 894Copyright (c) 1987, 1989, 1991, 1992, 1993, 1994, 1995, 1996,
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7951997, 1998, 1999, 2000, 2001
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8951997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 |
896Free Software Foundation, Inc. 897.PP 898Permission is granted to copy, distribute and/or modify this document 899under the terms of the \s-1GNU\s0 Free Documentation License, Version 1.1 or 900any later version published by the Free Software Foundation. A copy of 901the license is included in the 902man page \fIgfdl\fR\|(7). 903This manual contains no Invariant Sections. The Front-Cover Texts are 904(a) (see below), and the Back-Cover Texts are (b) (see below). 905.PP 906(a) The \s-1FSF\s0's Front-Cover Text is: 907.PP 908.Vb 1 909\& A GNU Manual 910.Ve
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911.PP |
912(b) The \s-1FSF\s0's Back-Cover Text is: 913.PP 914.Vb 3 915\& You have freedom to copy and modify this GNU Manual, like GNU 916\& software. Copies published by the Free Software Foundation raise 917\& funds for GNU development. 918.Ve
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