компилятор C и C ++ проекта GNU (GNU project C and C++ compiler)
Параметры подробно (Options detail)
Directory Search
These options specify directories to search for header files, for
libraries and for parts of the compiler:
-I dir
-iquote dir
-isystem dir
-idirafter dir
Add the directory dir to the list of directories to be
searched for header files during preprocessing. If dir
begins with = or $SYSROOT, then the = or $SYSROOT is replaced
by the sysroot prefix; see --sysroot and -isysroot.
Directories specified with -iquote apply only to the quote
form of the directive, "#include "file"". Directories
specified with -I, -isystem, or -idirafter apply to lookup
for both the "#include "file"" and "#include <file>"
directives.
You can specify any number or combination of these options on
the command line to search for header files in several
directories. The lookup order is as follows:
1. For the quote form of the include directive, the
directory of the current file is searched first.
2. For the quote form of the include directive, the
directories specified by -iquote options are searched in
left-to-right order, as they appear on the command line.
3. Directories specified with -I options are scanned in
left-to-right order.
4. Directories specified with -isystem options are scanned
in left-to-right order.
5. Standard system directories are scanned.
6. Directories specified with -idirafter options are scanned
in left-to-right order.
You can use -I to override a system header file, substituting
your own version, since these directories are searched before
the standard system header file directories. However, you
should not use this option to add directories that contain
vendor-supplied system header files; use -isystem for that.
The -isystem and -idirafter options also mark the directory
as a system directory, so that it gets the same special
treatment that is applied to the standard system directories.
If a standard system include directory, or a directory
specified with -isystem, is also specified with -I, the -I
option is ignored. The directory is still searched but as a
system directory at its normal position in the system include
chain. This is to ensure that GCC's procedure to fix buggy
system headers and the ordering for the "#include_next"
directive are not inadvertently changed. If you really need
to change the search order for system directories, use the
-nostdinc and/or -isystem options.
-I- Split the include path. This option has been deprecated.
Please use -iquote instead for -I directories before the -I-
and remove the -I- option.
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"". There is no way to override this effect
of -I-.
-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.
-nostdinc
Do not search the standard system directories for header
files. Only the directories explicitly specified with -I,
-iquote, -isystem, and/or -idirafter 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.)
-iplugindir=dir
Set the directory to search for plugins that are passed by
-fplugin=name instead of -fplugin=path/name.so. This option
is not meant to be used by the user, but only passed by the
driver.
-Ldir
Add directory dir to the list of directories to be searched
for -l.
-Bprefix
This option specifies where to find the executables,
libraries, include files, and data files of the compiler
itself.
The compiler driver program runs one or more of the
subprograms cpp, cc1, as and ld. It tries prefix as a prefix
for each program it tries to run, both with and without
machine/version/ for the corresponding target machine and
compiler version.
For each subprogram to be run, the compiler driver first
tries the -B prefix, if any. If that name is not found, or
if -B is not specified, the driver tries two standard
prefixes, /usr/lib/gcc/ and /usr/local/lib/gcc/. If neither
of those results in a file name that is found, the unmodified
program name is searched for using the directories specified
in your PATH environment variable.
The compiler checks to see if the path provided by -B refers
to a directory, and if necessary it adds a directory
separator character at the end of the path.
-B prefixes that effectively specify directory names also
apply to libraries in the linker, because the compiler
translates these options into -L options for the linker.
They also apply to include files in the preprocessor, because
the compiler translates these options into -isystem options
for the preprocessor. In this case, the compiler appends
include to the prefix.
The runtime support file libgcc.a can also be searched for
using the -B prefix, if needed. If it is not found there,
the two standard prefixes above are tried, and that is all.
The file is left out of the link if it is not found by those
means.
Another way to specify a prefix much like the -B prefix is to
use the environment variable GCC_EXEC_PREFIX.
As a special kludge, if the path provided by -B is
[dir/]stageN/, where N is a number in the range 0 to 9, then
it is replaced by [dir/]include. This is to help with boot-
strapping the compiler.
-no-canonical-prefixes
Do not expand any symbolic links, resolve references to /../
or /./, or make the path absolute when generating a relative
prefix.
--sysroot=dir
Use dir as the logical root directory for headers and
libraries. For example, if the compiler normally searches
for headers in /usr/include and libraries in /usr/lib, it
instead searches dir/usr/include and dir/usr/lib.
If you use both this option and the -isysroot option, then
the --sysroot option applies to libraries, but the -isysroot
option applies to header files.
The GNU linker (beginning with version 2.16) has the
necessary support for this option. If your linker does not
support this option, the header file aspect of --sysroot
still works, but the library aspect does not.
--no-sysroot-suffix
For some targets, a suffix is added to the root directory
specified with --sysroot, depending on the other options
used, so that headers may for example be found in
dir/suffix/usr/include instead of dir/usr/include. This
option disables the addition of such a suffix.
