[PATCH 2/4] DJGPP fix: do not try to source /dev/null as cache or site file.

[Ralf Wildenhues]

* lib/autoconf/general.m4 (AC_SITE_LOAD, AC_CACHE_LOAD): Do not
load the cache or site file if it is `/dev/null', as DJGPP treats
it as a regular file, but the shell then warns about it later.
Fixes several test suite failures on DJGPP.
---

* Ralf Wildenhues wrote on Sun, Sep 13, 2009 at 09:12:28PM CEST:
> -- 'test -f /dev/null && test -r /dev/null' returns true, but
> '. /dev/null' does not work.  Worked around with patch.
> 
> Test failures: 14 31 259-261 270-271 284-287


 lib/autoconf/general.m4 |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/autoconf/general.m4 b/lib/autoconf/general.m4
index b82999a..fd40c43 100644
--- a/lib/autoconf/general.m4
+++ b/lib/autoconf/general.m4
@@ -1875,7 +1875,7 @@ fi
 for ac_site_file in "$ac_site_file1" "$ac_site_file2"
 do
   test "x$ac_site_file" = xNONE && continue
-  if test -r "$ac_site_file"; then
+  if test /dev/null != "$ac_site_file" && test -r "$ac_site_file"; then
     AC_MSG_NOTICE([loading site script $ac_site_file])
     sed 's/^/| /' "$ac_site_file" >&AS_MESSAGE_LOG_FD
     . "$ac_site_file"
@@ -1888,9 +1888,9 @@ done
 # -------------
 m4_define([AC_CACHE_LOAD],
 [if test -r "$cache_file"; then
-  # Some versions of bash will fail to source /dev/null (special
-  # files actually), so we avoid doing that.
-  if test -f "$cache_file"; then
+  # Some versions of bash will fail to source /dev/null (special files
+  # actually), so we avoid doing that.  DJGPP emulates it as a regular file.
+  if test /dev/null != "$cache_file" && test -f "$cache_file"; then
     AC_MSG_NOTICE([loading cache $cache_file])
     case $cache_file in
       [[\\/]]* | ?:[[\\/]]* ) . "$cache_file";;
-- 
1.6.3.3.345.gb7132