diff --git a/BUGS_REPORTED.TXT b/BUGS_REPORTED.TXT
index b5c83d6da..c3e51ea77 100644
--- a/BUGS_REPORTED.TXT
+++ b/BUGS_REPORTED.TXT
@@ -1,5 +1,9 @@
 ===================================================================
 
+11/07/2011 (total 396)
+  1 clang crash bug reported
+  http://llvm.org/bugs/show_bug.cgi?id=11327
+
 08/10/2011 (total 395)
   1 gcc crash bug reported by Arthur O'Dwyer
   http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50039
diff --git a/runtime/csmith_minimal.h b/runtime/csmith_minimal.h
index f390892a1..9ba038e01 100644
--- a/runtime/csmith_minimal.h
+++ b/runtime/csmith_minimal.h
@@ -28,6 +28,8 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
+extern int printf (const char *, ...);
+
 // FIXME-- need more versions, and a way to figure out which is needed
 #include "custom_stdint_x86.h"
 
@@ -60,8 +62,6 @@ static inline void crc32_gentab (void)
 
 int crc32_context;
 
-extern int printf (const char *, ...);
-
 #ifdef TCC
 int strcmp (const char *s1, const char *s2)
 {
diff --git a/utah/scripts/reduce/simple_delta.pl b/utah/scripts/reduce/simple_delta.pl
index d0bb20d56..19cd18032 100755
--- a/utah/scripts/reduce/simple_delta.pl
+++ b/utah/scripts/reduce/simple_delta.pl
@@ -19,26 +19,34 @@
 my $CSMITH_HOME = $ENV{"CSMITH_HOME"};
 die "please set CSMITH_HOME env first!" if (!defined($CSMITH_HOME));
 
-my $VOLATILE = $ENV{"VOLATILE_HOME"};
-die "please set VOLATILE_HOME env first!" if (!defined($VOLATILE));
+#my $VOLATILE = $ENV{"VOLATILE_HOME"};
+#die "please set VOLATILE_HOME env first!" if (!defined($VOLATILE));
 
-$ENV{"PATH"} = "$ENV{VOLATILE_HOME}:$ENV{PATH}";
+#$ENV{"PATH"} = "$ENV{VOLATILE_HOME}:$ENV{PATH}";
 
 my $COMPILER_TIMEOUT = 600;
 my $PROG_TIMEOUT = 2;
 
-if (@ARGV != 4 && @ARGV != 3) {
-    die "usage: simple_delta.pl <seed> <compiler1> <compiler2> <csmith-options>\n\n";
+# in second
+my $TEST_TIMEOUT = 20 * 60;
+
+if (@ARGV != 4 && @ARGV != 3 && @ARGV != 5) {
+    die "usage: simple_delta.pl <seed> <compiler1> <compiler2> <csmith-options> <crash string>\n\n";
 }
 
 my $seed = $ARGV[0];
 my $COMPILER1 = $ARGV[1];
 my $COMPILER2 = $ARGV[2];
 my $OPTS = "--concise ";
-if (@ARGV == 4) {
+if (@ARGV >= 4) {
     $OPTS =  "$OPTS$ARGV[3]";
 }
 
+my $crash_string = "";
+if (@ARGV == 5) {
+  $crash_string = $ARGV[4];
+}
+
 my $cfile = "small.c"; 
 my $tmp_cfile = "small_tmp.c";
 my $backup_cfile = "works.c";
@@ -81,6 +89,21 @@ ($\@$)
     return $cnt;
 	      }
 
+sub read_file_with_substring($\@$) {
+    my ($input, $out, $substring) = @_;
+    my $cnt = 0;
+    open INF1, "<$input" or die;
+    while (my $line = <INF1>) {
+        chomp $line;
+        if (index($line, $substring) != -1) {
+            push @$out, $line;
+            $cnt++;
+        }
+    }
+    close INF1;
+    return $cnt;
+}
+
 sub compile($$$$) {
     my ($compiler, $src_file, $exe, $out) = @_;
     my $res = 0;
@@ -157,7 +180,7 @@ ($\@$\@$$)
 my $EXTRA='-Wuninitialized -Werror=uninitialized';
 # flag1 == 1: we check if two outputs have the same lines. 
 # flag2 == 1: we check the line which is "checksum = xxxx". 
-sub run_test ($$$) {
+sub run_wrong_code_test ($$$) {
     my ($test_file, $flag1, $match) = @_;
     system "rm -f gcc.txt";
     system "gcc $ARGS $EXTRA -O0 $test_file -o a.out > gcc.txt 2>&1";
@@ -207,6 +230,50 @@ ($$$)
     return $res;
 }
 
+sub run_crash_test($$) {
+    my ($test_file, $match) = @_;
+    system "rm -f gcc.txt";
+    system "gcc $ARGS $EXTRA -O0 $test_file -o a.out > gcc.txt 2>&1";
+    my @tmp = ();
+    if (read_file("gcc.txt", @tmp, "no return statement") || 
+	read_file("gcc.txt", @tmp, "control reaches") ||
+	# read_file("gcc.txt", @tmp, "initia") ||
+	read_file("gcc.txt", @tmp, "proto")) {
+	system("cp $test_file gcc_fail.c");
+	print "$indent compiler error! Can't compile $test_file with gcc\n";
+	return 0;
+    }
+    
+    $test_count++;
+    my $res;
+    $res = compile($COMPILER1, $test_file, "$EXE1$test_count", "$COMPILER_OUT1$test_count");
+    if ($res) {
+        if (read_file_with_substring("$COMPILER_OUT1$test_count", @tmp, $match)) {
+	    print "$indent crash string $match found for $test_file with $COMPILER1\n";
+            return 1;
+        }
+        else {
+	    print "$indent no crash string $match found for $test_file with $COMPILER1\n";
+	    return 0;
+        }
+    }
+    else {
+	print "$indent no crash error found for $test_file with $COMPILER1\n";
+	return 0;
+    }
+}
+
+sub run_test($$$) {
+    my ($test_file, $flag1, $match) = @_;
+
+    if ($crash_string eq "") {
+        return run_wrong_code_test($test_file, $flag1, $match);
+    }
+    else {
+        return run_crash_test($test_file, $crash_string);
+    }
+}
+
 sub get_score ($) {
     (my $fn) = @_;
     return stat($fn)->size;    
@@ -227,6 +294,8 @@ ($)
 
 print "seed = $seed\n";
 
+$OPTS =~ s/-s\s+[0-9]+//g;
+
 system "${CSMITH_HOME}/src/csmith -s $seed $OPTS --delta-monitor simple --delta-output $deltafile > $cfile";
 
 my $res = run_test($cfile, 0, "checksum ");
@@ -247,6 +316,8 @@ ($)
 my $orig_sz = get_score($cfile);
 
 my $n = 0;
+my $prev_time = time();
+my $total_time = 0;
 
 print "initial score = $orig_sz\n";
 while (1) {
@@ -289,6 +360,13 @@ ($)
     } else {
 	$sz = $new_sz;
     }
+    my $curr_time = time();
+    $total_time += ($curr_time - $prev_time);
+    $prev_time = $curr_time;
+    print "elapsed time: $total_time\n";
+    if ($total_time > $TEST_TIMEOUT) {
+        last;
+    }
 }
 system "cp $cfile simple$seed.c";
 my $sz = get_score($cfile);