* aclocal.m4 (AC_FUNC_MMAP_ANYWHERE): Extend test to detect systems

        with MAP_ANONYMOUS and MAP_ANON.
        * configure, config.in: Rebuilt.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@34977 138bc75d-0d04-0410-961f-82ee72b054a4

gcc/ChangeLog

+2000-07-11  J. David Anglin  <dave@hiauly1.hia.nrc.ca>
+
+	* aclocal.m4 (AC_FUNC_MMAP_ANYWHERE): Extend test to detect systems
+	with MAP_ANONYMOUS and MAP_ANON.
+	* configure, config.in: Rebuilt.
+
 2000-07-12  Gabriel Dos Reis  <gdr@codesourcery.com>
 	* diagnostic.c (save_output_state): Remove.

gcc/aclocal.m4

@@ -684,19 +684,24 @@ fi
 AC_SUBST($1)dnl
 ])
 
-# Check whether mmap can map an arbitrary page from /dev/zero, without
-# MAP_FIXED.
+# Check whether mmap can map an arbitrary page from /dev/zero or with
+# MAP_ANONYMOUS, without MAP_FIXED.
 AC_DEFUN([AC_FUNC_MMAP_ANYWHERE],
 [AC_CHECK_HEADERS(unistd.h)
 AC_CHECK_FUNCS(getpagesize)
-AC_CACHE_CHECK(for working mmap from /dev/zero, ac_cv_func_mmap_anywhere,
+AC_CACHE_CHECK(for working mmap which provides zeroed pages anywhere,
+  ac_cv_func_mmap_anywhere,
 [AC_TRY_RUN([
 /* Test by Richard Henderson and Alexandre Oliva.
-   Check whether mmap from /dev/zero works. */
+   Check whether mmap MAP_ANONYMOUS or mmap from /dev/zero works. */
 #include <sys/types.h>
 #include <fcntl.h>
 #include <sys/mman.h>
 
+#if !defined (MAP_ANONYMOUS) && defined (MAP_ANON)
+# define MAP_ANONYMOUS MAP_ANON
+#endif
+
 /* This mess was copied from the GNU getpagesize.h.  */
 #ifndef HAVE_GETPAGESIZE
 # ifdef HAVE_UNISTD_H
@@ -743,12 +748,19 @@ int main()
   char *x;
   int fd, pg;
 
+#ifndef MAP_ANONYMOUS
   fd = open("/dev/zero", O_RDWR);
   if (fd < 0)
     exit(1);
+#endif
 
   pg = getpagesize();
+#ifdef MAP_ANONYMOUS
+  x = (char*)mmap(0, pg, PROT_READ|PROT_WRITE,
+                  MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+#else
   x = (char*)mmap(0, pg, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
+#endif
   if (x == (char *) -1)
     exit(2);
 
@@ -762,7 +774,7 @@ int main()
 ac_cv_func_mmap_anywhere=no)])
 if test $ac_cv_func_mmap_anywhere = yes; then
   AC_DEFINE(HAVE_MMAP_ANYWHERE, 1,
-	    [Define if mmap can get us zeroed pages from /dev/zero.])
+	    [Define if mmap can get us zeroed pages without MAP_FIXED.])
 fi
 ])
 

gcc/config.in

@@ -313,7 +313,7 @@
 /* Define if printf supports %p. */
 #undef HAVE_PRINTF_PTR
 
-/* Define if mmap can get us zeroed pages from /dev/zero. */
+/* Define if mmap can get us zeroed pages without MAP_FIXED. */
 #undef HAVE_MMAP_ANYWHERE
 
 /* Define if read-only mmap of a plain file works. */