diff --git a/test/bench/mandelbrot.c b/test/bench/mandelbrot.c
new file mode 100644
index 00000000000..c177c088ca6
--- /dev/null
+++ b/test/bench/mandelbrot.c
@@ -0,0 +1,91 @@
+/*
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in the
+    documentation and/or other materials provided with the distribution.
+
+    * Neither the name of "The Computer Language Benchmarks Game" nor the
+    name of "The Computer Language Shootout Benchmarks" nor the names of
+    its contributors may be used to endorse or promote products derived
+    from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/* The Computer Language Shootout
+   http://shootout.alioth.debian.org/
+
+   contributed by Greg Buchholz
+
+   for the debian (AMD) machine...
+   compile flags:  -O3 -ffast-math -march=athlon-xp -funroll-loops
+
+   for the gp4 (Intel) machine...
+   compile flags:  -O3 -ffast-math -march=pentium4 -funroll-loops
+*/
+
+#include<stdio.h>
+
+int main (int argc, char **argv)
+{
+    int w, h, bit_num = 0;
+    char byte_acc = 0;
+    int i, iter = 50;
+    double x, y, limit = 2.0;
+    double Zr, Zi, Cr, Ci, Tr, Ti;
+
+    w = h = atoi(argv[1]);
+
+    printf("P4\n%d %d\n",w,h);
+
+    for(y=0;y<h;++y)
+    {
+        for(x=0;x<w;++x)
+        {
+            Zr = Zi = Tr = Ti = 0.0;
+            Cr = (2.0*x/w - 1.5); Ci=(2.0*y/h - 1.0);
+
+            for (i=0;i<iter && (Tr+Ti <= limit*limit);++i)
+            {
+                Zi = 2.0*Zr*Zi + Ci;
+                Zr = Tr - Ti + Cr;
+                Tr = Zr * Zr;
+                Ti = Zi * Zi;
+            }
+
+            byte_acc <<= 1;
+            if(Tr+Ti <= limit*limit) byte_acc |= 0x01;
+
+            ++bit_num;
+
+            if(bit_num == 8)
+            {
+                putc(byte_acc,stdout);
+                byte_acc = 0;
+                bit_num = 0;
+            }
+            else if(x == w-1)
+            {
+                byte_acc <<= (8-w%8);
+                putc(byte_acc,stdout);
+                byte_acc = 0;
+                bit_num = 0;
+            }
+        }
+    }
+}
diff --git a/test/bench/mandelbrot.go b/test/bench/mandelbrot.go
new file mode 100644
index 00000000000..1bd9f6b758a
--- /dev/null
+++ b/test/bench/mandelbrot.go
@@ -0,0 +1,95 @@
+/*
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in the
+    documentation and/or other materials provided with the distribution.
+
+    * Neither the name of "The Computer Language Benchmarks Game" nor the
+    name of "The Computer Language Shootout Benchmarks" nor the names of
+    its contributors may be used to endorse or promote products derived
+    from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/* The Computer Language Benchmarks Game
+ * http://shootout.alioth.debian.org/
+ *
+ * contributed by The Go Authors.
+ * Based on mandelbrot.c contributed by Greg Buchholz
+*/
+
+package main
+
+import (
+	"bufio";
+	"flag";
+	"fmt";
+	"os";
+)
+
+var n = flag.Int("n", 200, "size")
+
+func main() {
+	flag.Parse();
+	out := bufio.NewWriter(os.Stdout);
+	defer out.Flush();
+
+	w := *n;
+	h := *n;
+	bit_num := 0;
+	byte_acc := byte(0);
+	const Iter = 50;
+	const Zero float64 = 0;
+	const Limit = 2.0;
+
+	fmt.Fprintf(out, "P4\n%d %d\n", w, h);
+
+	for y := 0; y < h; y++ {
+		for x := 0; x<w; x++ {
+			Zr, Zi, Tr, Ti := Zero, Zero, Zero, Zero;
+			Cr := (2*float64(x)/float64(w) - 1.5);
+			Ci := (2*float64(y)/float64(h) - 1.0);
+
+			for i := 0; i < Iter && (Tr+Ti <= Limit*Limit); i++ {
+				Zi = 2*Zr*Zi + Ci;
+				Zr = Tr - Ti + Cr;
+				Tr = Zr * Zr;
+				Ti = Zi * Zi;
+			}
+
+			byte_acc <<= 1;
+			if Tr+Ti <= Limit*Limit {
+				byte_acc |= 0x01;
+			}
+
+			bit_num++;
+
+			if bit_num == 8 {
+				out.WriteByte(byte_acc);
+				byte_acc = 0;
+				bit_num = 0;
+			} else if x == w-1 {
+				byte_acc <<= uint(8-w%8);
+				out.WriteByte(byte_acc);
+				byte_acc = 0;
+				bit_num = 0;
+			}
+		}
+	}
+}
diff --git a/test/bench/mandelbrot.txt b/test/bench/mandelbrot.txt
new file mode 100644
index 00000000000..2f7bbbc6b0a
Binary files /dev/null and b/test/bench/mandelbrot.txt differ
diff --git a/test/bench/timing.log b/test/bench/timing.log
index d1731386e8f..520b18dd05b 100644
--- a/test/bench/timing.log
+++ b/test/bench/timing.log
@@ -1,4 +1,4 @@
-All tests on r45
+All tests on r45 or r70
 
 Aug 3 2009
 
@@ -73,3 +73,10 @@ k-nucleotide 5000000
 	gcc -O2 -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include k-nucleotide.c -lglib-2.0	k-nucleotide.c: 10.72u 0.01s 10.74r
 	gccgo -O2 k-nucleotide.go	22.69u 0.85s 24.09r
 	gc k-nucleotide	15.63u 0.26s 16.41r
+	gc_B k-nucleotide	17.22u 0.04s 17.28r
+
+mandelbrot 5500
+	gcc -O2 mandelbrot.c	56.13u 0.02s 56.17r
+	gccgo -O2 mandelbrot.go	57.49u 0.01s 57.51r
+	gc mandelbrot	74.32u 0.00s 74.35r
+	gc_B mandelbrot	74.28u 0.01s 74.31r
diff --git a/test/bench/timing.sh b/test/bench/timing.sh
index 7af19194f51..600cacb91c1 100755
--- a/test/bench/timing.sh
+++ b/test/bench/timing.sh
@@ -91,12 +91,21 @@ knucleotide() {
 	run 'gcc -O2 -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include k-nucleotide.c -lglib-2.0' a.out <x
 	run 'gccgo -O2 k-nucleotide.go' a.out <x	# warning: pages badly!
 	run 'gc k-nucleotide' $O.out <x
+	run 'gc_B k-nucleotide' $O.out <x
 	rm x
 }
 
+mandelbrot() {
+	echo 'mandelbrot 16000'
+	run 'gcc -O2 mandelbrot.c' a.out 16000
+	run 'gccgo -O2 mandelbrot.go' a.out -n 16000
+	run 'gc mandelbrot' $O.out -n 16000
+	run 'gc_B mandelbrot' $O.out -n 16000
+}
+
 case $# in
 0)
-	run="fasta revcom nbody binarytree fannkuch regexdna spectralnorm knucleotide"
+	run="fasta revcom nbody binarytree fannkuch regexdna spectralnorm knucleotide mandelbrot"
 	;;
 *)
 	run=$*