fix CPPOUTFILE

* configure.in (RUBY_CPPOUTFILE): check if output file is actually
  created.  [ruby-dev:45742] [Bug#6591]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@36086 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Thu Jun 14 22:49:44 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* configure.in (RUBY_CPPOUTFILE): check if output file is actually
+	  created.  [ruby-dev:45742] [Bug#6591]
+
 Thu Jun 14 22:10:50 2012  Tanaka Akira  <akr@fsij.org>
 
 	* process.c (proc_exec_sh): don't strip leading spaces of the script.

configure.in

@@ -137,8 +137,9 @@ AC_DEFUN([RUBY_NACL_CHECK_PEPPER_TYPES],
 AC_DEFUN([RUBY_CPPOUTFILE],
 [AC_CACHE_CHECK(whether ${CPP} accepts -o, rb_cv_cppoutfile,
 [cppflags=$CPPFLAGS
-CPPFLAGS='-o conftest.i'
-AC_TRY_CPP([], rb_cv_cppoutfile=yes, rb_cv_cppoutfile=no)
+CPPFLAGS='-o conftest-1.i'
+rb_cv_cppoutfile=no
+AC_TRY_CPP([], [test -f conftest-1.i && rb_cv_cppoutfile=yes])
 CPPFLAGS=$cppflags
 rm -f conftest*])
 if test "$rb_cv_cppoutfile" = yes; then