diff --git a/SConscript b/SConscript
index 7d8d9f50e..b159d3e36 100644
--- a/SConscript
+++ b/SConscript
@@ -310,7 +310,8 @@ env.Command(Split('''arch/alpha/decoder.cc
 		     arch/alpha/fast_cpu_exec.cc
                      arch/alpha/simple_cpu_exec.cc
                      arch/alpha/full_cpu_exec.cc'''),
-            'arch/alpha/isa_desc',
+            Split('''arch/alpha/isa_desc
+		     arch/isa_parser.py'''),
             '$SRCDIR/arch/isa_parser.py $SOURCE $TARGET.dir arch/alpha')