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Diffstat (limited to 'gcc/fortran/invoke.texi')
| -rw-r--r-- | gcc/fortran/invoke.texi | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/gcc/fortran/invoke.texi b/gcc/fortran/invoke.texi index 88ede3b2a13..1494c04013e 100644 --- a/gcc/fortran/invoke.texi +++ b/gcc/fortran/invoke.texi @@ -94,6 +94,7 @@ one is not the default. without explanations. * Fortran Dialect Options:: Controlling the variant of Fortran language compiled. +* Preprocessing Options:: Enable and customize preprocessing. * Error and Warning Options:: How picky should the compiler be? * Debugging Options:: Symbol tables, measurements, and debugging dumps. * Directory Options:: Where to find module files @@ -123,6 +124,14 @@ by type. Explanations are in the following sections. -fdefault-double-8 -fdefault-integer-8 -fdefault-real-8 @gol -fcray-pointer -fopenmp -fno-range-check -fbackslash -fmodule-private} +@item Preprocessing Options +@xref{Preprocessing Options,,Enable and customize preprocessing}. +@gccoptlist{-cpp -dD -dI -dM -dN -dU -fworking-directory @gol +-imultilib @var{dir} -iprefix @var{file} -isysroot @var{dir} @gol +-iquote -isystem @var{dir} -nocpp -nostdinc -undef @gol +-A@var{question}=@var{answer} -A-@var{question}@r{[}=@var{answer}@r{]} @gol +-C -CC -D@var{macro}@r{[}=@var{defn}@r{]} -U@var{macro} -H -P} + @item Error and Warning Options @xref{Error and Warning Options,,Options to request or suppress errors and warnings}. @@ -164,6 +173,7 @@ and warnings}. @menu * Fortran Dialect Options:: Controlling the variant of Fortran language compiled. +* Preprocessing Options:: Enable and customize preprocessing. * Error and Warning Options:: How picky should the compiler be? * Debugging Options:: Symbol tables, measurements, and debugging dumps. * Directory Options:: Where to find module files @@ -341,6 +351,238 @@ that are permitted but obsolescent in later standards. @end table +@node Preprocessing Options +@section Enable and customize preprocessing +@cindex preprocessor +@cindex options, preprocessor +@cindex CPP + +Preprocessor related options. See section +@ref{Preprocessing and conditional compilation} for more detailed +information on preprocessing in @command{gfortran}. + +@table @gcctabopt +@item -cpp +@item -nocpp +@opindex @code{cpp} +@opindex @code{fpp} +@cindex preprocessor, enable +@cindex preprocessor, disable +Enable preprocessing. The preprocessor is automatically invoked if +the file extension is @file{.fpp}, @file{.FPP}, @file{.F}, @file{.FOR}, +@file{.FTN}, @file{.F90}, @file{.F95}, @file{.F03} or @file{.F08}. Use +this option to manually enable preprocessing of any kind of Fortran file. + +To disable preprocessing of files with any of the above listed extensions, +use the negative form: @option{-nocpp}. + +The preprocessor is run in traditional mode, be aware that any +restrictions of the file-format, e.g. fixed-form line width, +apply for preprocessed output as well. + +@item -dM +@opindex @code{dM} +@cindex preprocessor, debugging +@cindex debugging, preprocessor +Instead of the normal output, generate a list of @code{'#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 @file{foo.f90}, the command +@smallexample + touch foo.f90; gfortran -cpp -dM foo.f90 +@end smallexample +will show all the predefined macros. + +@item -dD +@opindex @code{dD} +@cindex preprocessor, debugging +@cindex debugging, preprocessor +Like @option{-dM} except in two respects: it does not include the +predefined macros, and it outputs both the @code{#define} directives +and the result of preprocessing. Both kinds of output go to the +standard output file. + +@item -dN +@opindex @code{dN} +@cindex preprocessor, debugging +@cindex debugging, preprocessor +Like @option{-dD}, but emit only the macro names, not their expansions. + +@item -dU +@opindex @code{dU} +@cindex preprocessor, debugging +@cindex debugging, preprocessor +Like @option{dD} 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 @code{'#undef'} +directives are also output for macros tested but undefined at the time. + +@item -dI +@opindex @code{dI} +@cindex preprocessor, debugging +@cindex debugging, preprocessor +Output @code{'#include'} directives in addition to the result +of preprocessing. + +@item -fworking-directory +@opindex @code{fworking-directory} +@cindex preprocessor, working 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 +@option{-fno-working-directory}. If the @option{-P} flag is present +in the command line, this option has no effect, since no @code{#line} +directives are emitted whatsoever. + +@item -imultilib @var{dir} +@opindex @code{imultilib @var{dir}} +@cindex preprocessing, include path +Use @var{dir} as a subdirectory of the directory containing target-specific +C++ headers. + +@item -iprefix @var{prefix} +@opindex @code{iprefix @var{prefix}} +@cindex preprocessing, include path +Specify @var{prefix} as the prefix for subsequent @option{-iwithprefix} +options. If the @var{prefix} represents a directory, you should include +the final @code{'/'}. + +@item -isysroot @var{dir} +@opindex @code{isysroot @var{dir}} +@cindex preprocessing, include path +This option is like the @option{--sysroot} option, but applies only to +header files. See the @option{--sysroot} option for more information. + +@item -iquote @var{dir} +@opindex @code{iquote @var{dir}} +@cindex preprocessing, include path +Search @var{dir} only for header files requested with @code{#include "file"}; +they are not searched for @code{#include <file>}, before all directories +specified by @option{-I} and before the standard system directories. If +@var{dir} begins with @code{=}, then the @code{=} will be replaced by the +sysroot prefix; see @option{--sysroot} and @option{-isysroot}. + +@item -isystem @var{dir} +@opindex @code{isystem @var{dir}} +@cindex preprocessing, include path +Search @var{dir} for header files, after all directories specified by +@option{-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 @var{dir} begins with +@code{=}, then the @code{=} will be replaced by the sysroot prefix; +see @option{--sysroot} and @option{-isysroot}. + +@item -nostdinc +@opindex @code{nostdinc} +Do not search the standard system directories for header files. Only +the directories you have specified with @option{-I} options (and the +directory of the current file, if appropriate) are searched. + +@item -undef +@opindex @code{undef} +Do not predefine any system-specific or GCC-specific macros. +The standard predefined macros remain defined. + +@item -A@var{predicate}=@var{answer} +@opindex @code{A@var{predicate}=@var{answer}} +@cindex preprocessing, assertation +Make an assertion with the predicate @var{predicate} and answer @var{answer}. +This form is preferred to the older form -A predicate(answer), which is still +supported, because it does not use shell special characters. + +@item -A-@var{predicate}=@var{answer} +@opindex @code{A-@var{predicate}=@var{answer}} +@cindex preprocessing, assertation +Cancel an assertion with the predicate @var{predicate} and answer @var{answer}. + +@item -C +@opindex @code{C} +@cindex preprocessing, keep comments +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 @option{-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 @code{'#'}. + +Warning: this currently handles C-Style comments only. The preprocessor +does not yet recognize Fortran-style comments. + +@item -CC +@opindex @code{CC} +@cindex preprocessing, keep comments +Do not discard comments, including during macro expansion. This is like +@option{-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 @option{-C} option, the @option{-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 @option{-CC} option +is generally used to support lint comments. + +Warning: this currently handles C- and C++-Style comments only. The +preprocessor does not yet recognize Fortran-style comments. + +@item -D@var{name} +@opindex @code{D@var{name}} +@cindex preprocessing, define macros +Predefine name as a macro, with definition @code{1}. + +@item -D@var{name}=@var{definition} +@opindex @code{D@var{name}=@var{definition}} +@cindex preprocessing, define macros +The contents of @var{definition} are tokenized and processed as if they +appeared during translation phase three in a @code{'#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, @code{-D'name(args...)=definition'} +works. + +@option{-D} and @option{-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. + +@item -H +@opindex @code{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 @code{'#include'} +stack it is. + +@item -P +@opindex @code{P} +@cindex preprocessing, no linemarkers +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. + +@item -U@var{name} +@opindex @code{U@var{name}} +@cindex preprocessing, undefine macros +Cancel any previous definition of @var{name}, either built in or provided +with a @option{-D} option. +@end table + + @node Error and Warning Options @section Options to request or suppress errors and warnings @cindex options, warnings |
