diff --git a/loopy/target/ispc.py b/loopy/target/ispc.py
index 57c2206379c15de6a9cef7e66c3d4433024febc9..8ab556929b54a0e8b5721300041be0c55432e9af 100644
--- a/loopy/target/ispc.py
+++ b/loopy/target/ispc.py
@@ -184,7 +184,7 @@ class ISPCTarget(CTarget):
         if gsize:
             launch_spec = "[%s]" % ", ".join(
                                 ccm(gs_i, PREC_NONE)
-                                for gs_i in gsize),
+                                for gs_i in gsize)
         else:
             launch_spec = ""