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Added add'l generated files for release
author lost
date Tue, 22 Dec 2009 05:33:32 +0000
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266:5f25e7afac21 267:bec6d2480f08
1 # include_next.m4 serial 12
2 dnl Copyright (C) 2006-2009 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
6
7 dnl From Paul Eggert and Derek Price.
8
9 dnl Sets INCLUDE_NEXT and PRAGMA_SYSTEM_HEADER.
10 dnl
11 dnl INCLUDE_NEXT expands to 'include_next' if the compiler supports it, or to
12 dnl 'include' otherwise.
13 dnl
14 dnl INCLUDE_NEXT_AS_FIRST_DIRECTIVE expands to 'include_next' if the compiler
15 dnl supports it in the special case that it is the first include directive in
16 dnl the given file, or to 'include' otherwise.
17 dnl
18 dnl PRAGMA_SYSTEM_HEADER can be used in files that contain #include_next,
19 dnl so as to avoid GCC warnings when the gcc option -pedantic is used.
20 dnl '#pragma GCC system_header' has the same effect as if the file was found
21 dnl through the include search path specified with '-isystem' options (as
22 dnl opposed to the search path specified with '-I' options). Namely, gcc
23 dnl does not warn about some things, and on some systems (Solaris and Interix)
24 dnl __STDC__ evaluates to 0 instead of to 1. The latter is an undesired side
25 dnl effect; we are therefore careful to use 'defined __STDC__' or '1' instead
26 dnl of plain '__STDC__'.
27
28 AC_DEFUN([gl_INCLUDE_NEXT],
29 [
30 AC_LANG_PREPROC_REQUIRE()
31 AC_CACHE_CHECK([whether the preprocessor supports include_next],
32 [gl_cv_have_include_next],
33 [rm -rf conftestd1a conftestd1b conftestd2
34 mkdir conftestd1a conftestd1b conftestd2
35 dnl IBM C 9.0, 10.1 (original versions, prior to the 2009-01 updates) on
36 dnl AIX 6.1 support include_next when used as first preprocessor directive
37 dnl in a file, but not when preceded by another include directive. Check
38 dnl for this bug by including <stdio.h>.
39 dnl Additionally, with this same compiler, include_next is a no-op when
40 dnl used in a header file that was included by specifying its absolute
41 dnl file name. Despite these two bugs, include_next is used in the
42 dnl compiler's <math.h>. By virtue of the second bug, we need to use
43 dnl include_next as well in this case.
44 cat <<EOF > conftestd1a/conftest.h
45 #define DEFINED_IN_CONFTESTD1
46 #include_next <conftest.h>
47 #ifdef DEFINED_IN_CONFTESTD2
48 int foo;
49 #else
50 #error "include_next doesn't work"
51 #endif
52 EOF
53 cat <<EOF > conftestd1b/conftest.h
54 #define DEFINED_IN_CONFTESTD1
55 #include <stdio.h>
56 #include_next <conftest.h>
57 #ifdef DEFINED_IN_CONFTESTD2
58 int foo;
59 #else
60 #error "include_next doesn't work"
61 #endif
62 EOF
63 cat <<EOF > conftestd2/conftest.h
64 #ifndef DEFINED_IN_CONFTESTD1
65 #error "include_next test doesn't work"
66 #endif
67 #define DEFINED_IN_CONFTESTD2
68 EOF
69 gl_save_CPPFLAGS="$CPPFLAGS"
70 CPPFLAGS="$gl_save_CPPFLAGS -Iconftestd1b -Iconftestd2"
71 AC_COMPILE_IFELSE([#include <conftest.h>],
72 [gl_cv_have_include_next=yes],
73 [CPPFLAGS="$gl_save_CPPFLAGS -Iconftestd1a -Iconftestd2"
74 AC_COMPILE_IFELSE([#include <conftest.h>],
75 [gl_cv_have_include_next=buggy],
76 [gl_cv_have_include_next=no])
77 ])
78 CPPFLAGS="$gl_save_CPPFLAGS"
79 rm -rf conftestd1a conftestd1b conftestd2
80 ])
81 PRAGMA_SYSTEM_HEADER=
82 if test $gl_cv_have_include_next = yes; then
83 INCLUDE_NEXT=include_next
84 INCLUDE_NEXT_AS_FIRST_DIRECTIVE=include_next
85 if test -n "$GCC"; then
86 PRAGMA_SYSTEM_HEADER='#pragma GCC system_header'
87 fi
88 else
89 if test $gl_cv_have_include_next = buggy; then
90 INCLUDE_NEXT=include
91 INCLUDE_NEXT_AS_FIRST_DIRECTIVE=include_next
92 else
93 INCLUDE_NEXT=include
94 INCLUDE_NEXT_AS_FIRST_DIRECTIVE=include
95 fi
96 fi
97 AC_SUBST([INCLUDE_NEXT])
98 AC_SUBST([INCLUDE_NEXT_AS_FIRST_DIRECTIVE])
99 AC_SUBST([PRAGMA_SYSTEM_HEADER])
100 ])
101
102 # gl_CHECK_NEXT_HEADERS(HEADER1 HEADER2 ...)
103 # ------------------------------------------
104 # For each arg foo.h, if #include_next works, define NEXT_FOO_H to be
105 # '<foo.h>'; otherwise define it to be
106 # '"///usr/include/foo.h"', or whatever other absolute file name is suitable.
107 # That way, a header file with the following line:
108 # #@INCLUDE_NEXT@ @NEXT_FOO_H@
109 # behaves (after sed substitution) as if it contained
110 # #include_next <foo.h>
111 # even if the compiler does not support include_next.
112 # The three "///" are to pacify Sun C 5.8, which otherwise would say
113 # "warning: #include of /usr/include/... may be non-portable".
114 # Use `""', not `<>', so that the /// cannot be confused with a C99 comment.
115 # Note: This macro assumes that the header file is not empty after
116 # preprocessing, i.e. it does not only define preprocessor macros but also
117 # provides some type/enum definitions or function/variable declarations.
118 AC_DEFUN([gl_CHECK_NEXT_HEADERS],
119 [
120 AC_REQUIRE([gl_INCLUDE_NEXT])
121 AC_REQUIRE([AC_CANONICAL_HOST])
122 AC_CHECK_HEADERS_ONCE([$1])
123
124 m4_foreach_w([gl_HEADER_NAME], [$1],
125 [AS_VAR_PUSHDEF([gl_next_header],
126 [gl_cv_next_]m4_quote(m4_defn([gl_HEADER_NAME])))
127 if test $gl_cv_have_include_next = yes; then
128 AS_VAR_SET([gl_next_header], ['<'gl_HEADER_NAME'>'])
129 else
130 AC_CACHE_CHECK(
131 [absolute name of <]m4_quote(m4_defn([gl_HEADER_NAME]))[>],
132 m4_quote(m4_defn([gl_next_header])),
133 [AS_VAR_PUSHDEF([gl_header_exists],
134 [ac_cv_header_]m4_quote(m4_defn([gl_HEADER_NAME])))
135 if test AS_VAR_GET(gl_header_exists) = yes; then
136 AC_LANG_CONFTEST(
137 [AC_LANG_SOURCE(
138 [[#include <]]m4_dquote(m4_defn([gl_HEADER_NAME]))[[>]]
139 )])
140 dnl AIX "xlc -E" and "cc -E" omit #line directives for header files
141 dnl that contain only a #include of other header files and no
142 dnl non-comment tokens of their own. This leads to a failure to
143 dnl detect the absolute name of <dirent.h>, <signal.h>, <poll.h>
144 dnl and others. The workaround is to force preservation of comments
145 dnl through option -C. This ensures all necessary #line directives
146 dnl are present. GCC supports option -C as well.
147 case "$host_os" in
148 aix*) gl_absname_cpp="$ac_cpp -C" ;;
149 *) gl_absname_cpp="$ac_cpp" ;;
150 esac
151 dnl eval is necessary to expand gl_absname_cpp.
152 dnl Ultrix and Pyramid sh refuse to redirect output of eval,
153 dnl so use subshell.
154 AS_VAR_SET([gl_next_header],
155 ['"'`(eval "$gl_absname_cpp conftest.$ac_ext") 2>&AS_MESSAGE_LOG_FD |
156 sed -n '\#/]m4_quote(m4_defn([gl_HEADER_NAME]))[#{
157 s#.*"\(.*/]m4_quote(m4_defn([gl_HEADER_NAME]))[\)".*#\1#
158 s#^/[^/]#//&#
159 p
160 q
161 }'`'"'])
162 else
163 AS_VAR_SET([gl_next_header], ['<'gl_HEADER_NAME'>'])
164 fi
165 AS_VAR_POPDEF([gl_header_exists])])
166 fi
167 AC_SUBST(
168 AS_TR_CPP([NEXT_]m4_quote(m4_defn([gl_HEADER_NAME]))),
169 [AS_VAR_GET([gl_next_header])])
170 AS_VAR_POPDEF([gl_next_header])])
171 ])