1# m4.m4 serial 12 2 3# Copyright (C) 2000, 2006-2012 Free Software Foundation, Inc. 4 5# Copying and distribution of this file, with or without modification, 6# are permitted in any medium without royalty provided the copyright 7# notice and this notice are preserved. This file is offered as-is, 8# without warranty of any kind. 9 10# AC_PROG_GNU_M4 11# -------------- 12# Check for GNU M4, at least 1.4.6 (all earlier versions had bugs in 13# trace support and regexp support): 14# http://lists.gnu.org/archive/html/bug-gnu-utils/2006-11/msg00096.html 15# http://lists.gnu.org/archive/html/bug-autoconf/2009-07/msg00023.html 16# Also, check whether --error-output (through 1.4.x) or --debugfile (2.0) 17# is supported, and AC_SUBST M4_DEBUGFILE accordingly. 18# Also avoid versions of m4 that trigger strstr bugs. 19AC_DEFUN([AC_PROG_GNU_M4], 20 [AC_ARG_VAR([M4], [Location of GNU M4 1.4.6 or later. Defaults to the first 21 program of 'm4', 'gm4', or 'gnum4' on PATH that meets Autoconf needs.]) 22 AC_CACHE_CHECK([for GNU M4 that supports accurate traces], [ac_cv_path_M4], 23 [rm -f conftest.m4f 24ac_had_posixly_correct=${POSIXLY_CORRECT:+yes} 25AS_UNSET([POSIXLY_CORRECT]) 26AC_PATH_PROGS_FEATURE_CHECK([M4], [m4 gm4 gnum4], 27 [dnl Creative quoting here to avoid raw dnl and ifdef in configure. 28 # Root out GNU M4 1.4.5, as well as non-GNU m4 that ignore -t, -F. 29 # Root out GNU M4 1.4.15 with buggy false negative replacement strstr. 30 # Root out Glibc 2.9 - 2.12 and GNU M4 1.4.11 - 1.4.15 with buggy 31 # false positive strstr. 32 ac_snippet=change'quote(<,>)in''dir(<if''def>,mac,bug)' 33 ac_snippet=${ac_snippet}pat'subst(a,\(b\)\|\(a\),\1)d'nl 34 ac_snippet=${ac_snippet}${as_nl}if'else(in''dex(..wi.d.,.d.),-1,bug)' 35 ac_snippet=${ac_snippet}${as_nl}if'else(in''dex(dnl 36;:11-:12-:12-:12-:12-:12-:12-:12-:12.:12.:12.:12.:12.:12.:12.:12.:12-,dnl 37:12-:12-:12-:12-:12-:12-:12-:12-),-1,,strstr-bug2)' 38 test -z "`$ac_path_M4 -F conftest.m4f </dev/null 2>&1`" \ 39 && test -z "`AS_ECHO([$ac_snippet]) | $ac_path_M4 --trace=mac 2>&1`" \ 40 && test -f conftest.m4f \ 41 && ac_cv_path_M4=$ac_path_M4 ac_path_M4_found=: 42 rm -f conftest.m4f], 43 [AC_MSG_ERROR([no acceptable m4 could be found in \$PATH. 44GNU M4 1.4.6 or later is required; 1.4.16 or newer is recommended. 45GNU M4 1.4.15 uses a buggy replacement strstr on some systems. 46Glibc 2.9 - 2.12 and GNU M4 1.4.11 - 1.4.15 have another strstr bug.])])]) 47 M4=$ac_cv_path_M4 48 AC_CACHE_CHECK([whether $ac_cv_path_M4 accepts --gnu], 49 [ac_cv_prog_gnu_m4_gnu], 50 [case `$M4 --help < /dev/null 2>&1` in 51 *--gnu*) ac_cv_prog_gnu_m4_gnu=yes ;; 52 *) ac_cv_prog_gnu_m4_gnu=no ;; 53 esac]) 54 if test "$ac_cv_prog_gnu_m4_gnu" = yes; then 55 M4_GNU=--gnu 56 else 57 M4_GNU= 58 fi 59 AC_SUBST([M4_GNU]) 60 if test x$ac_had_posixly_correct = xyes; then 61 POSIXLY_CORRECT=: 62 if test $ac_cv_prog_gnu_m4_gnu = no; then 63 AC_MSG_WARN([the version of M4 that was found does not support -g]) 64 AC_MSG_WARN([using it with POSIXLY_CORRECT set may cause problems]) 65 fi 66 fi 67 AC_CACHE_CHECK([how m4 supports trace files], [ac_cv_prog_gnu_m4_debugfile], 68 [case `$M4 --help < /dev/null 2>&1` in 69 *debugfile*) ac_cv_prog_gnu_m4_debugfile=--debugfile ;; 70 *) ac_cv_prog_gnu_m4_debugfile=--error-output ;; 71 esac]) 72 AC_SUBST([M4_DEBUGFILE], [$ac_cv_prog_gnu_m4_debugfile]) 73]) 74 75# Compatibility for bootstrapping with Autoconf 2.61. 76dnl FIXME - replace this with AC_PREREQ([2.62]) after the release. 77# AC_PATH_PROGS_FEATURE_CHECK was added the same time the slightly broken, 78# undocumented _AC_PATH_PROG_FEATURE_CHECK was deleted. 79m4_ifndef([AC_PATH_PROGS_FEATURE_CHECK], 80 [m4_define([AC_PATH_PROGS_FEATURE_CHECK], 81 [_AC_PATH_PROG_FEATURE_CHECK([$1], [$2], [$3], [$5]) 82])]) 83