Once again, reject IRIX m4.

* m4/m4.m4 (AC_PROG_GNU_M4): Use indir builtin to root out non-GNU
implementations that ignore --trace.
* configure: Regenerate.
Reported by Ralf Wildenhues.

Signed-off-by: Eric Blake <ebb9@byu.net>

diff --git a/ChangeLog b/ChangeLog
index 1e0920156feacd7a49d5bf7734d1a0762bd6f124..1a3b08ddf5e0bfb99a304a4d1f740ed74bc29490 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2007-10-01  Eric Blake  <ebb9@byu.net>
 
+       Once again, reject IRIX m4.
+       * m4/m4.m4 (AC_PROG_GNU_M4): Use indir builtin to root out non-GNU
+       implementations that ignore --trace.
+       * configure: Regenerate.
+       Reported by Ralf Wildenhues.
+
        Fix regression in AC_DEFINE([macro(with_arg)]).
        * lib/autoconf/general.m4 (AC_DEFINE_TRACE): Don't chop off close
        quotes with a careless m4_substr.

diff --git a/configure b/configure
index f0b5215ebf0a54bc2003cfcbc31de50d822c3f5c..434301a82a28bd16fb442dfdd9d9d8488f542db2 100755 (executable)
--- a/configure
+++ b/configure
@@ -2362,7 +2362,9 @@ do
     for ac_exec_ext in '' $ac_executable_extensions; do
       ac_path_M4="$as_dir/$ac_prog$ac_exec_ext"
       { test -f "$ac_path_M4" && $as_test_x "$ac_path_M4"; } || continue
-      test -z "`echo if'def(mac,bug)d'nl | $ac_path_M4 --trace=mac 2>&1`" \
+      # Root out GNU M4 1.4.4, as well as non-GNU m4 that ignore --trace.
+      ac_snippet=change'quote(<,>)in''dir(<if''def>,mac,bug)d'nl
+      test -z "`echo $ac_snippet | $ac_path_M4 --trace=mac 2>&1`" \
       && ac_cv_path_M4=$ac_path_M4 ac_path_M4_found=:
       $ac_path_M4_found && break 3
     done

diff --git a/m4/m4.m4 b/m4/m4.m4
index 70f30767d6b1b1b7a41c511a4d3677d2e1faca0c..711bd58a4d68ca7edb7cf60eae89ff69f378ed14 100644 (file)
--- a/m4/m4.m4
+++ b/m4/m4.m4
@@ -17,7 +17,9 @@ AC_DEFUN([AC_PROG_GNU_M4],
   AC_CACHE_CHECK([for GNU M4 that supports accurate traces], [ac_cv_path_M4],
     [AC_PATH_PROGS_FEATURE_CHECK([M4], [m4 gm4 gnum4],
       [dnl Creative quoting here to avoid raw dnl and ifdef in configure.
-      test -z "`echo if'def(mac,bug)d'nl | $ac_path_M4 --trace=mac 2>&1`" \
+      # Root out GNU M4 1.4.4, as well as non-GNU m4 that ignore --trace.
+      ac_snippet=change'quote(<,>)in''dir(<if''def>,mac,bug)d'nl
+      test -z "`echo $ac_snippet | $ac_path_M4 --trace=mac 2>&1`" \
       && ac_cv_path_M4=$ac_path_M4 ac_path_M4_found=:],
       [AC_MSG_ERROR([no acceptable m4 could be found in \$PATH.
 GNU M4 1.4.5 or later is required; 1.4.8 is recommended])])])