Some DJGPP tweaks

[Tim Van Holder]

First off, I'd like to request that the -*-Shell-script-*-
markers be replaced by -*-autoconf-*-, as shell-script-mode
in emacs gets the fontification all wrong, making the files
hard to edit.

These changes are required for current libtool CVS HEAD to work
properly on DJGPP.  The SYS_MAX_CMD_LEN patch is critical; otherwise
the test will have effects ranging from slowdowns (> 5 mions for the
test) to system reboots.  The change to AC_LIBTOOL_SYS_GLOBAL_SYMBOL_PIPE
is required for that test to succeed, but isn't critical because the
result is probably not needed on DJGPP (no shared libs).

2001-06-24  Tim Van Holder  <address@hidden>

        * libtool.m4: Use the canonical absolute path test
        ([\\/]* | ?:[\\/]) and $lt_cv_sys_path_separator wherever
        appropriate.
        (AC_LIBTOOL_PROG_CC_PIC): Properly recognize DJGPP as a
        platform that doesn't support shared libraries.
        (AC_LIBTOOL_SYS_MAX_CMD_LEN): Avoid this test on DJGPP; use a
        fixed value (12K) instead.
        (AC_LIBTOOL_SYS_GLOBAL_SYMBOL_PIPE): Don't forget $ac_exeext
        when testing for link success.

Index: libtool.m4
===================================================================
RCS file: /home/cvs/libtool/libtool.m4,v
retrieving revision 1.170
diff -u -u -r1.170 libtool.m4
--- libtool.m4  2001/06/06 22:06:57     1.170
+++ libtool.m4  2001/06/24 15:17:35
@@ -534,6 +534,13 @@
 AC_DEFUN([AC_LIBTOOL_SYS_MAX_CMD_LEN],
 [max_cmd_len=
 # find the maximum length of command line arguments
+dnl On DJGPP, this test can blow up pretty badly due to problems in libc
+dnl (any single argument exceeding 2000 bytes causes a buffer overrun
during
+dnl glob expansion).  Even if it were fixed, the result of this check would
+dnl be larger than it should be.  So override it here.
+case $host_os in
+  msdosdjgpp*) lt_cv_sys_max_cmd_len=12288;; # 12K is about right
+esac
 AC_MSG_CHECKING([the maximum length of command line arguments])
 AC_CACHE_VAL([lt_cv_sys_max_cmd_len], [dnl
   i=0
@@ -703,7 +710,7 @@
          save_CFLAGS="$CFLAGS"
          LIBS="conftstm.$ac_objext"
          CFLAGS="$CFLAGS$no_builtin_flag"
-         if AC_TRY_EVAL(ac_link) && test -s conftest; then
+         if AC_TRY_EVAL(ac_link) && test -s conftest$ac_exeext; then
            pipe_works=yes
          fi
          LIBS="$save_LIBS"
@@ -1052,15 +1059,17 @@
       # Common symbols not allowed in MH_DYLIB files
       lt_cv_prog_cc_pic='-fno-common'
       ;;
-    *djgpp*)
-      # DJGPP does not support shared libraries at all
-      lt_cv_prog_cc_pic=
-      ;;
+    msdosdjgpp*)
+      # Just because we use GCC doesn't mean we suddenly get shared
libraries
+      # on systems that don't support them.
+      enable_shared=no
+      lt_cv_prog_cc_can_build_shared=no
+      ;;
     sysv4*MP*)
       if test -d /usr/nec; then
         lt_cv_prog_cc_pic=-Kconform_pic
       fi
       ;;
     *)
       lt_cv_prog_cc_pic='-fPIC'
       ;;
@@ -3297,15 +3310,12 @@
 [AC_MSG_CHECKING([for $1])
 AC_CACHE_VAL(lt_cv_path_MAGIC_CMD,
 [case $MAGIC_CMD in
-  /*)
-  lt_cv_path_MAGIC_CMD="$MAGIC_CMD" # Let the user override the test with a
path.
-  ;;
-  ?:/*)
-  lt_cv_path_MAGIC_CMD="$MAGIC_CMD" # Let the user override the test with a
dos path.
+  [\\/*] |  ?:[\\/]*)
+  lt_cv_path_MAGIC_CMD="$MAGIC_CMD" # Let the user override the test with a
path.
   ;;
   *)
   ac_save_MAGIC_CMD="$MAGIC_CMD"
-  IFS="${IFS=   }"; ac_save_ifs="$IFS"; IFS=":"
+  IFS="${IFS=   }"; ac_save_ifs="$IFS"; IFS="$lt_cv_sys_path_separator"
 dnl $ac_dummy forces splitting on constant user-supplied paths.
 dnl POSIX.2 word splitting is done only on the output of word expansions,
 dnl not every word.  This closes a longstanding sh security hole.
@@ -3362,7 +3372,7 @@
 AC_PATH_TOOL_PREFIX(${ac_tool_prefix}file, /usr/bin:$PATH)
 if test -z "$lt_cv_path_MAGIC_CMD"; then
   if test -n "$ac_tool_prefix"; then
-    AC_PATH_TOOL_PREFIX(file, /usr/bin:$PATH)
+    AC_PATH_TOOL_PREFIX(file, "/usr/bin$lt_cv_sys_path_separator$PATH")
   else
     MAGIC_CMD=:
   fi
@@ -3393,7 +3403,7 @@
   esac
   case $ac_prog in
     # Accept absolute paths.
-    [[\\/]* | [A-Za-z]:[\\/]*)]
+    [[\\/]]* | ?:[[\\/]]*)
       [re_direlt='/[^/][^/]*/\.\./']
       # Canonicalize the path of ld
       ac_prog=`echo $ac_prog| sed 's%\\\\%/%g'`
@@ -3418,7 +3428,7 @@
 fi
 AC_CACHE_VAL(lt_cv_path_LD,
 [if test -z "$LD"; then
-  IFS="${IFS=  }"; ac_save_ifs="$IFS"; IFS="${IFS}${PATH_SEPARATOR-:}"
+  IFS="${IFS=  }"; ac_save_ifs="$IFS";
IFS="${IFS}$lt_cv_sys_path_separator"
   for ac_dir in $PATH; do
     test -z "$ac_dir" && ac_dir=.
     if test -f "$ac_dir/$ac_prog" || test -f "$ac_dir/$ac_prog$ac_exeext";
then
@@ -3663,7 +3673,7 @@
   # Let the user override the test.
   lt_cv_path_NM="$NM"
 else
-  IFS="${IFS=  }"; ac_save_ifs="$IFS"; IFS="${IFS}${PATH_SEPARATOR-:}"
+  IFS="${IFS=  }"; ac_save_ifs="$IFS";
IFS="${IFS}$lt_cv_sys_path_separator"
   for ac_dir in $PATH /usr/ccs/bin /usr/ucb /bin; do
     test -z "$ac_dir" && ac_dir=.
     tmp_nm=$ac_dir/${ac_tool_prefix}nm