X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Finclude_next.m4;h=108d945677fc5d4713c43fde800ce6bd876e17d3;hb=5191b3546cfb6c163228c23f214e325ddf60d46f;hp=b6e4d3ae7a92c2e1a7c83b5325a31fadf25f8ff7;hpb=62c4adfccd0e9155a6c1682511f3dc6a1d527c35;p=gnulib.git diff --git a/m4/include_next.m4 b/m4/include_next.m4 index b6e4d3ae7..108d94567 100644 --- a/m4/include_next.m4 +++ b/m4/include_next.m4 @@ -1,5 +1,5 @@ -# include_next.m4 serial 8 -dnl Copyright (C) 2006-2008 Free Software Foundation, Inc. +# include_next.m4 serial 23 +dnl Copyright (C) 2006-2013 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. @@ -11,6 +11,10 @@ dnl dnl INCLUDE_NEXT expands to 'include_next' if the compiler supports it, or to dnl 'include' otherwise. dnl +dnl INCLUDE_NEXT_AS_FIRST_DIRECTIVE expands to 'include_next' if the compiler +dnl supports it in the special case that it is the first include directive in +dnl the given file, or to 'include' otherwise. +dnl dnl PRAGMA_SYSTEM_HEADER can be used in files that contain #include_next, dnl so as to avoid GCC warnings when the gcc option -pedantic is used. dnl '#pragma GCC system_header' has the same effect as if the file was found @@ -20,18 +24,40 @@ dnl does not warn about some things, and on some systems (Solaris and Interix) dnl __STDC__ evaluates to 0 instead of to 1. The latter is an undesired side dnl effect; we are therefore careful to use 'defined __STDC__' or '1' instead dnl of plain '__STDC__'. +dnl +dnl PRAGMA_COLUMNS can be used in files that override system header files, so +dnl as to avoid compilation errors on HP NonStop systems when the gnulib file +dnl is included by a system header file that does a "#pragma COLUMNS 80" (which +dnl has the effect of truncating the lines of that file and all files that it +dnl includes to 80 columns) and the gnulib file has lines longer than 80 +dnl columns. AC_DEFUN([gl_INCLUDE_NEXT], [ AC_LANG_PREPROC_REQUIRE() AC_CACHE_CHECK([whether the preprocessor supports include_next], [gl_cv_have_include_next], - [rm -rf conftestd1 conftestd2 - mkdir conftestd1 conftestd2 - dnl The include of is because IBM C 9.0 on AIX 6.1 supports - dnl include_next when used as first preprocessor directive in a file, - dnl but not when preceded by another include directive. - cat < conftestd1/conftest.h + [rm -rf conftestd1a conftestd1b conftestd2 + mkdir conftestd1a conftestd1b conftestd2 + dnl IBM C 9.0, 10.1 (original versions, prior to the 2009-01 updates) on + dnl AIX 6.1 support include_next when used as first preprocessor directive + dnl in a file, but not when preceded by another include directive. Check + dnl for this bug by including . + dnl Additionally, with this same compiler, include_next is a no-op when + dnl used in a header file that was included by specifying its absolute + dnl file name. Despite these two bugs, include_next is used in the + dnl compiler's . By virtue of the second bug, we need to use + dnl include_next as well in this case. + cat < conftestd1a/conftest.h +#define DEFINED_IN_CONFTESTD1 +#include_next +#ifdef DEFINED_IN_CONFTESTD2 +int foo; +#else +#error "include_next doesn't work" +#endif +EOF + cat < conftestd1b/conftest.h #define DEFINED_IN_CONFTESTD1 #include #include_next @@ -47,25 +73,56 @@ EOF #endif #define DEFINED_IN_CONFTESTD2 EOF - save_CPPFLAGS="$CPPFLAGS" - CPPFLAGS="$CPPFLAGS -Iconftestd1 -Iconftestd2" - AC_COMPILE_IFELSE([#include ], + gl_save_CPPFLAGS="$CPPFLAGS" + CPPFLAGS="$gl_save_CPPFLAGS -Iconftestd1b -Iconftestd2" +dnl We intentionally avoid using AC_LANG_SOURCE here. + AC_COMPILE_IFELSE([AC_LANG_DEFINES_PROVIDED[#include ]], [gl_cv_have_include_next=yes], - [gl_cv_have_include_next=no]) - CPPFLAGS="$save_CPPFLAGS" - rm -rf conftestd1 conftestd2 + [CPPFLAGS="$gl_save_CPPFLAGS -Iconftestd1a -Iconftestd2" + AC_COMPILE_IFELSE([AC_LANG_DEFINES_PROVIDED[#include ]], + [gl_cv_have_include_next=buggy], + [gl_cv_have_include_next=no]) + ]) + CPPFLAGS="$gl_save_CPPFLAGS" + rm -rf conftestd1a conftestd1b conftestd2 ]) PRAGMA_SYSTEM_HEADER= if test $gl_cv_have_include_next = yes; then INCLUDE_NEXT=include_next + INCLUDE_NEXT_AS_FIRST_DIRECTIVE=include_next if test -n "$GCC"; then PRAGMA_SYSTEM_HEADER='#pragma GCC system_header' fi else - INCLUDE_NEXT=include + if test $gl_cv_have_include_next = buggy; then + INCLUDE_NEXT=include + INCLUDE_NEXT_AS_FIRST_DIRECTIVE=include_next + else + INCLUDE_NEXT=include + INCLUDE_NEXT_AS_FIRST_DIRECTIVE=include + fi fi AC_SUBST([INCLUDE_NEXT]) + AC_SUBST([INCLUDE_NEXT_AS_FIRST_DIRECTIVE]) AC_SUBST([PRAGMA_SYSTEM_HEADER]) + AC_CACHE_CHECK([whether system header files limit the line length], + [gl_cv_pragma_columns], + [dnl HP NonStop systems, which define __TANDEM, have this misfeature. + AC_EGREP_CPP([choke me], + [ +#ifdef __TANDEM +choke me +#endif + ], + [gl_cv_pragma_columns=yes], + [gl_cv_pragma_columns=no]) + ]) + if test $gl_cv_pragma_columns = yes; then + PRAGMA_COLUMNS="#pragma COLUMNS 10000" + else + PRAGMA_COLUMNS= + fi + AC_SUBST([PRAGMA_COLUMNS]) ]) # gl_CHECK_NEXT_HEADERS(HEADER1 HEADER2 ...) @@ -73,56 +130,141 @@ EOF # For each arg foo.h, if #include_next works, define NEXT_FOO_H to be # ''; otherwise define it to be # '"///usr/include/foo.h"', or whatever other absolute file name is suitable. +# Also, if #include_next works as first preprocessing directive in a file, +# define NEXT_AS_FIRST_DIRECTIVE_FOO_H to be ''; otherwise define it to +# be +# '"///usr/include/foo.h"', or whatever other absolute file name is suitable. # That way, a header file with the following line: -# #@INCLUDE_NEXT@ @NEXT_FOO_H@ +# #@INCLUDE_NEXT@ @NEXT_FOO_H@ +# or +# #@INCLUDE_NEXT_AS_FIRST_DIRECTIVE@ @NEXT_AS_FIRST_DIRECTIVE_FOO_H@ # behaves (after sed substitution) as if it contained -# #include_next +# #include_next # even if the compiler does not support include_next. # The three "///" are to pacify Sun C 5.8, which otherwise would say # "warning: #include of /usr/include/... may be non-portable". -# Use `""', not `<>', so that the /// cannot be confused with a C99 comment. +# Use '""', not '<>', so that the /// cannot be confused with a C99 comment. # Note: This macro assumes that the header file is not empty after # preprocessing, i.e. it does not only define preprocessor macros but also # provides some type/enum definitions or function/variable declarations. +# +# This macro also checks whether each header exists, by invoking +# AC_CHECK_HEADERS_ONCE or AC_CHECK_HEADERS on each argument. AC_DEFUN([gl_CHECK_NEXT_HEADERS], [ + gl_NEXT_HEADERS_INTERNAL([$1], [check]) +]) + +# gl_NEXT_HEADERS(HEADER1 HEADER2 ...) +# ------------------------------------ +# Like gl_CHECK_NEXT_HEADERS, except do not check whether the headers exist. +# This is suitable for headers like that are standardized by C89 +# and therefore can be assumed to exist. +AC_DEFUN([gl_NEXT_HEADERS], +[ + gl_NEXT_HEADERS_INTERNAL([$1], [assume]) +]) + +# The guts of gl_CHECK_NEXT_HEADERS and gl_NEXT_HEADERS. +AC_DEFUN([gl_NEXT_HEADERS_INTERNAL], +[ AC_REQUIRE([gl_INCLUDE_NEXT]) - AC_CHECK_HEADERS_ONCE([$1]) + AC_REQUIRE([AC_CANONICAL_HOST]) + + m4_if([$2], [check], + [AC_CHECK_HEADERS_ONCE([$1]) + ]) +dnl FIXME: gl_next_header and gl_header_exists must be used unquoted +dnl until we can assume autoconf 2.64 or newer. m4_foreach_w([gl_HEADER_NAME], [$1], [AS_VAR_PUSHDEF([gl_next_header], - [gl_cv_next_]m4_quote(m4_defn([gl_HEADER_NAME]))) + [gl_cv_next_]m4_defn([gl_HEADER_NAME])) if test $gl_cv_have_include_next = yes; then - AS_VAR_SET([gl_next_header], ['<'gl_HEADER_NAME'>']) + AS_VAR_SET(gl_next_header, ['<'gl_HEADER_NAME'>']) else AC_CACHE_CHECK( - [absolute name of <]m4_quote(m4_defn([gl_HEADER_NAME]))[>], - m4_quote(m4_defn([gl_next_header])), - [AS_VAR_PUSHDEF([gl_header_exists], - [ac_cv_header_]m4_quote(m4_defn([gl_HEADER_NAME]))) - if test AS_VAR_GET(gl_header_exists) = yes; then - AC_LANG_CONFTEST( - [AC_LANG_SOURCE( - [[#include <]]m4_dquote(m4_defn([gl_HEADER_NAME]))[[>]] - )]) - dnl eval is necessary to expand ac_cpp. - dnl Ultrix and Pyramid sh refuse to redirect output of eval, - dnl so use subshell. - AS_VAR_SET([gl_next_header], - ['"'`(eval "$ac_cpp conftest.$ac_ext") 2>&AS_MESSAGE_LOG_FD | - sed -n '\#/]m4_quote(m4_defn([gl_HEADER_NAME]))[#{ - s#.*"\(.*/]m4_quote(m4_defn([gl_HEADER_NAME]))[\)".*#\1# - s#^/[^/]#//&# - p - q - }'`'"']) - else - AS_VAR_SET([gl_next_header], ['<'gl_HEADER_NAME'>']) - fi - AS_VAR_POPDEF([gl_header_exists])]) + [absolute name of <]m4_defn([gl_HEADER_NAME])[>], + m4_defn([gl_next_header]), + [m4_if([$2], [check], + [AS_VAR_PUSHDEF([gl_header_exists], + [ac_cv_header_]m4_defn([gl_HEADER_NAME])) + if test AS_VAR_GET(gl_header_exists) = yes; then + AS_VAR_POPDEF([gl_header_exists]) + ]) + AC_LANG_CONFTEST( + [AC_LANG_SOURCE( + [[#include <]]m4_dquote(m4_defn([gl_HEADER_NAME]))[[>]] + )]) + dnl AIX "xlc -E" and "cc -E" omit #line directives for header + dnl files that contain only a #include of other header files and + dnl no non-comment tokens of their own. This leads to a failure + dnl to detect the absolute name of , , + dnl and others. The workaround is to force preservation + dnl of comments through option -C. This ensures all necessary + dnl #line directives are present. GCC supports option -C as well. + case "$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"`'"']) + m4_if([$2], [check], + [else + AS_VAR_SET(gl_next_header, ['<'gl_HEADER_NAME'>']) + fi + ]) + ]) fi AC_SUBST( - AS_TR_CPP([NEXT_]m4_quote(m4_defn([gl_HEADER_NAME]))), - [AS_VAR_GET([gl_next_header])]) + AS_TR_CPP([NEXT_]m4_defn([gl_HEADER_NAME])), + [AS_VAR_GET(gl_next_header)]) + if test $gl_cv_have_include_next = yes || test $gl_cv_have_include_next = buggy; then + # INCLUDE_NEXT_AS_FIRST_DIRECTIVE='include_next' + gl_next_as_first_directive='<'gl_HEADER_NAME'>' + else + # INCLUDE_NEXT_AS_FIRST_DIRECTIVE='include' + gl_next_as_first_directive=AS_VAR_GET(gl_next_header) + fi + AC_SUBST( + AS_TR_CPP([NEXT_AS_FIRST_DIRECTIVE_]m4_defn([gl_HEADER_NAME])), + [$gl_next_as_first_directive]) AS_VAR_POPDEF([gl_next_header])]) ]) + +# Autoconf 2.68 added warnings for our use of AC_COMPILE_IFELSE; +# this fallback is safe for all earlier autoconf versions. +m4_define_default([AC_LANG_DEFINES_PROVIDED])