|
145
|
1 @c Copyright (C) 1999-2020 Free Software Foundation, Inc.
|
|
111
|
2 @c This is part of the CPP and GCC manuals.
|
|
|
3 @c For copying conditions, see the file gcc.texi.
|
|
|
4
|
|
|
5 @c ---------------------------------------------------------------------
|
|
|
6 @c Options affecting include directory search in the preprocessor
|
|
|
7 @c ---------------------------------------------------------------------
|
|
|
8
|
|
|
9 @c If this file is included with the flag ``cppmanual'' set, it is
|
|
|
10 @c formatted for inclusion in the CPP manual; otherwise the main GCC manual.
|
|
|
11
|
|
|
12 @item -I @var{dir}
|
|
|
13 @itemx -iquote @var{dir}
|
|
|
14 @itemx -isystem @var{dir}
|
|
|
15 @itemx -idirafter @var{dir}
|
|
|
16 @opindex I
|
|
|
17 @opindex iquote
|
|
|
18 @opindex isystem
|
|
|
19 @opindex idirafter
|
|
|
20 Add the directory @var{dir} to the list of directories to be searched
|
|
|
21 for header files during preprocessing.
|
|
|
22 @ifset cppmanual
|
|
|
23 @xref{Search Path}.
|
|
|
24 @end ifset
|
|
|
25 If @var{dir} begins with @samp{=} or @code{$SYSROOT}, then the @samp{=}
|
|
|
26 or @code{$SYSROOT} is replaced by the sysroot prefix; see
|
|
|
27 @option{--sysroot} and @option{-isysroot}.
|
|
|
28
|
|
|
29 Directories specified with @option{-iquote} apply only to the quote
|
|
|
30 form of the directive, @code{@w{#include "@var{file}"}}.
|
|
|
31 Directories specified with @option{-I}, @option{-isystem},
|
|
|
32 or @option{-idirafter} apply to lookup for both the
|
|
|
33 @code{@w{#include "@var{file}"}} and
|
|
|
34 @code{@w{#include <@var{file}>}} directives.
|
|
|
35
|
|
|
36 You can specify any number or combination of these options on the
|
|
|
37 command line to search for header files in several directories.
|
|
|
38 The lookup order is as follows:
|
|
|
39
|
|
|
40 @enumerate
|
|
|
41 @item
|
|
|
42 For the quote form of the include directive, the directory of the current
|
|
|
43 file is searched first.
|
|
|
44
|
|
|
45 @item
|
|
|
46 For the quote form of the include directive, the directories specified
|
|
|
47 by @option{-iquote} options are searched in left-to-right order,
|
|
|
48 as they appear on the command line.
|
|
|
49
|
|
|
50 @item
|
|
|
51 Directories specified with @option{-I} options are scanned in
|
|
|
52 left-to-right order.
|
|
|
53
|
|
|
54 @item
|
|
|
55 Directories specified with @option{-isystem} options are scanned in
|
|
|
56 left-to-right order.
|
|
|
57
|
|
|
58 @item
|
|
|
59 Standard system directories are scanned.
|
|
|
60
|
|
|
61 @item
|
|
|
62 Directories specified with @option{-idirafter} options are scanned in
|
|
|
63 left-to-right order.
|
|
|
64 @end enumerate
|
|
|
65
|
|
|
66 You can use @option{-I} to override a system header
|
|
|
67 file, substituting your own version, since these directories are
|
|
|
68 searched before the standard system header file directories.
|
|
|
69 However, you should
|
|
|
70 not use this option to add directories that contain vendor-supplied
|
|
|
71 system header files; use @option{-isystem} for that.
|
|
|
72
|
|
|
73 The @option{-isystem} and @option{-idirafter} options also mark the directory
|
|
|
74 as a system directory, so that it gets the same special treatment that
|
|
|
75 is applied to the standard system directories.
|
|
|
76 @ifset cppmanual
|
|
|
77 @xref{System Headers}.
|
|
|
78 @end ifset
|
|
|
79
|
|
|
80 If a standard system include directory, or a directory specified with
|
|
|
81 @option{-isystem}, is also specified with @option{-I}, the @option{-I}
|
|
|
82 option is ignored. The directory is still searched but as a
|
|
|
83 system directory at its normal position in the system include chain.
|
|
|
84 This is to ensure that GCC's procedure to fix buggy system headers and
|
|
|
85 the ordering for the @code{#include_next} directive are not inadvertently
|
|
|
86 changed.
|
|
|
87 If you really need to change the search order for system directories,
|
|
|
88 use the @option{-nostdinc} and/or @option{-isystem} options.
|
|
|
89 @ifset cppmanual
|
|
|
90 @xref{System Headers}.
|
|
|
91 @end ifset
|
|
|
92
|
|
|
93 @item -I-
|
|
|
94 @opindex I-
|
|
|
95 Split the include path.
|
|
|
96 This option has been deprecated. Please use @option{-iquote} instead for
|
|
|
97 @option{-I} directories before the @option{-I-} and remove the @option{-I-}
|
|
|
98 option.
|
|
|
99
|
|
|
100 Any directories specified with @option{-I}
|
|
|
101 options before @option{-I-} are searched only for headers requested with
|
|
|
102 @code{@w{#include "@var{file}"}}; they are not searched for
|
|
|
103 @code{@w{#include <@var{file}>}}. If additional directories are
|
|
|
104 specified with @option{-I} options after the @option{-I-}, those
|
|
|
105 directories are searched for all @samp{#include} directives.
|
|
|
106
|
|
|
107 In addition, @option{-I-} inhibits the use of the directory of the current
|
|
|
108 file directory as the first search directory for @code{@w{#include
|
|
|
109 "@var{file}"}}. There is no way to override this effect of @option{-I-}.
|
|
|
110 @ifset cppmanual
|
|
|
111 @xref{Search Path}.
|
|
|
112 @end ifset
|
|
|
113
|
|
|
114 @item -iprefix @var{prefix}
|
|
|
115 @opindex iprefix
|
|
|
116 Specify @var{prefix} as the prefix for subsequent @option{-iwithprefix}
|
|
|
117 options. If the prefix represents a directory, you should include the
|
|
|
118 final @samp{/}.
|
|
|
119
|
|
|
120 @item -iwithprefix @var{dir}
|
|
|
121 @itemx -iwithprefixbefore @var{dir}
|
|
|
122 @opindex iwithprefix
|
|
|
123 @opindex iwithprefixbefore
|
|
|
124 Append @var{dir} to the prefix specified previously with
|
|
|
125 @option{-iprefix}, and add the resulting directory to the include search
|
|
|
126 path. @option{-iwithprefixbefore} puts it in the same place @option{-I}
|
|
|
127 would; @option{-iwithprefix} puts it where @option{-idirafter} would.
|
|
|
128
|
|
|
129 @item -isysroot @var{dir}
|
|
|
130 @opindex isysroot
|
|
|
131 This option is like the @option{--sysroot} option, but applies only to
|
|
|
132 header files (except for Darwin targets, where it applies to both header
|
|
|
133 files and libraries). See the @option{--sysroot} option for more
|
|
|
134 information.
|
|
|
135
|
|
|
136 @item -imultilib @var{dir}
|
|
|
137 @opindex imultilib
|
|
|
138 Use @var{dir} as a subdirectory of the directory containing
|
|
|
139 target-specific C++ headers.
|
|
|
140
|
|
|
141 @item -nostdinc
|
|
|
142 @opindex nostdinc
|
|
|
143 Do not search the standard system directories for header files.
|
|
|
144 Only the directories explicitly specified with @option{-I},
|
|
|
145 @option{-iquote}, @option{-isystem}, and/or @option{-idirafter}
|
|
|
146 options (and the directory of the current file, if appropriate)
|
|
|
147 are searched.
|
|
|
148
|
|
|
149 @item -nostdinc++
|
|
|
150 @opindex nostdinc++
|
|
|
151 Do not search for header files in the C++-specific standard directories,
|
|
|
152 but do still search the other standard directories. (This option is
|
|
|
153 used when building the C++ library.)
|
|
|
154
|
