1 files changed, 6 insertions, 1 deletions
diff --git a/compiler/cmm/Cmm.hs b/compiler/cmm/Cmm.hs
index 2dedee0d52..8409f0dbeb 100644
--- a/compiler/cmm/Cmm.hs
+++ b/compiler/cmm/Cmm.hs
@@ -109,9 +109,14 @@ data CmmStackInfo
                -- number of bytes of arguments on the stack on entry to the
                -- the proc.  This is filled in by StgCmm.codeGen, and used
                -- by the stack allocator later.
-       updfr_space :: Maybe ByteOff
+       updfr_space :: Maybe ByteOff,
                -- XXX: this never contains anything useful, but it should.
                -- See comment in CmmLayoutStack.
+       do_layout :: Bool
+               -- Do automatic stack layout for this proc.  This is
+               -- True for all code generated by the code generator,
+               -- but is occasionally False for hand-written Cmm where
+               -- we want to do the stack manipulation manually.
   }
 
 -- | Info table as a haskell data type