tree.c (append_random_chars): Generate the random characters in a reproducable fashion.

	* tree.c (append_random_chars): Generate the random
	characters in a reproducable fashion.

From-SVN: r45606

1 files changed, 13 insertions, 11 deletions

diff --git a/gcc/tree.c b/gcc/tree.c
index d3db289..14d4807 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -4533,19 +4533,21 @@ append_random_chars (template)
   static unsigned HOST_WIDE_INT value;
   unsigned HOST_WIDE_INT v;
 
-#ifdef HAVE_GETTIMEOFDAY
-  struct timeval tv;
-#endif
+  if (! value)
+    {
+      struct stat st;
 
-  template += strlen (template);
+      /* VALUE should be unique for each file and must
+	 not change between compiles since this can cause
+	 bootstrap comparison errors.  */
 
-#ifdef HAVE_GETTIMEOFDAY
-  /* Get some more or less random data.  */
-  gettimeofday (&tv, NULL);
-  value += ((unsigned HOST_WIDE_INT) tv.tv_usec << 16) ^ tv.tv_sec ^ getpid ();
-#else
-  value += getpid ();
-#endif
+      if (stat (main_input_filename, &st) < 0)
+	abort ();
+
+      value = st.st_dev ^ st.st_ino ^ st.st_mtime;
+    }
+
+  template += strlen (template);
 
   v = value;