delete trailing whitespace from control files
[debian/gzip] / m4 / include_next.m4
index a60a2614dc841971ce82e960a5c9322dc0541efc..a363cb013beb44e1dccc70315eba0aae121d453d 100644 (file)
@@ -1,12 +1,13 @@
-# include_next.m4 serial 23
-dnl Copyright (C) 2006-2012 Free Software Foundation, Inc.
+# include_next.m4 serial 24
+dnl Copyright (C) 2006-2018 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
 dnl From Paul Eggert and Derek Price.
 
-dnl Sets INCLUDE_NEXT and PRAGMA_SYSTEM_HEADER.
+dnl Sets INCLUDE_NEXT, INCLUDE_NEXT_AS_FIRST_DIRECTIVE, PRAGMA_SYSTEM_HEADER,
+dnl and PRAGMA_COLUMNS.
 dnl
 dnl INCLUDE_NEXT expands to 'include_next' if the compiler supports it, or to
 dnl 'include' otherwise.
@@ -192,56 +193,9 @@ dnl until we can assume autoconf 2.64 or newer.
              if test AS_VAR_GET(gl_header_exists) = yes; then
              AS_VAR_POPDEF([gl_header_exists])
             ])
-               AC_LANG_CONFTEST(
-                 [AC_LANG_SOURCE(
-                    [[#include <]]m4_dquote(m4_defn([gl_HEADER_NAME]))[[>]]
-                  )])
-               dnl AIX "xlc -E" and "cc -E" omit #line directives for header
-               dnl files that contain only a #include of other header files and
-               dnl no non-comment tokens of their own. This leads to a failure
-               dnl to detect the absolute name of <dirent.h>, <signal.h>,
-               dnl <poll.h> and others. The workaround is to force preservation
-               dnl of comments through option -C. This ensures all necessary
-               dnl #line directives are present. GCC supports option -C as well.
-               case "$host_os" in
-                 aix*) gl_absname_cpp="$ac_cpp -C" ;;
-                 *)    gl_absname_cpp="$ac_cpp" ;;
-               esac
-changequote(,)
-               case "$host_os" in
-                 mingw*)
-                   dnl For the sake of native Windows compilers (excluding gcc),
-                   dnl treat backslash as a directory separator, like /.
-                   dnl Actually, these compilers use a double-backslash as
-                   dnl directory separator, inside the
-                   dnl   # line "filename"
-                   dnl directives.
-                   gl_dirsep_regex='[/\\]'
-                   ;;
-                 *)
-                   gl_dirsep_regex='\/'
-                   ;;
-               esac
-               dnl A sed expression that turns a string into a basic regular
-               dnl expression, for use within "/.../".
-               gl_make_literal_regex_sed='s,[]$^\\.*/[],\\&,g'
-changequote([,])
-               gl_header_literal_regex=`echo ']m4_defn([gl_HEADER_NAME])[' \
-                                        | sed -e "$gl_make_literal_regex_sed"`
-               gl_absolute_header_sed="/${gl_dirsep_regex}${gl_header_literal_regex}/"'{
-                   s/.*"\(.*'"${gl_dirsep_regex}${gl_header_literal_regex}"'\)".*/\1/
-changequote(,)dnl
-                   s|^/[^/]|//&|
-changequote([,])dnl
-                   p
-                   q
-                 }'
-               dnl eval is necessary to expand gl_absname_cpp.
-               dnl Ultrix and Pyramid sh refuse to redirect output of eval,
-               dnl so use subshell.
-               AS_VAR_SET(gl_next_header,
-                 ['"'`(eval "$gl_absname_cpp conftest.$ac_ext") 2>&AS_MESSAGE_LOG_FD |
-                      sed -n "$gl_absolute_header_sed"`'"'])
+           gl_ABSOLUTE_HEADER_ONE(gl_HEADER_NAME)
+           AS_VAR_COPY([gl_header], [gl_cv_absolute_]AS_TR_SH(gl_HEADER_NAME))
+           AS_VAR_SET(gl_next_header, ['"'$gl_header'"'])
           m4_if([$2], [check],
             [else
                AS_VAR_SET(gl_next_header, ['<'gl_HEADER_NAME'>'])