The cc option is generally used to support lint

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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. See Chapter 10 [Traditional Mode], page 48 . -trigraphs Process trigraph sequences. See Section 1.2 [Initial processing], page 2 . -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. Precom- piled 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. 13 Environment Variables 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 ’ (see Chapter 12 [Invocation], page 56 ). These take precedence over environment variables, which in turn take precedence over the configuration of GCC.
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Chapter 13: Environment Variables 67 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 Mi- crosoft 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 par- ticular 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 ’.
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