X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fmain%2FHscTypes.lhs;h=1d3f4dcc7cac5d95a6c2750ea90082d19f7cefd8;hb=5e0453cad41cb0f004c1680b392d79651053a1d4;hp=0d83a925ee437b11332d418061ad3e999c93e41f;hpb=e06951a75a1f519e8f015880c363a8dedc08ff9c;p=ghc-hetmet.git

diff --git a/compiler/main/HscTypes.lhs b/compiler/main/HscTypes.lhs
index 0d83a92..1d3f4dc 100644
--- a/compiler/main/HscTypes.lhs
+++ b/compiler/main/HscTypes.lhs
@@ -1992,8 +1992,14 @@ data Linkable = LM {
 					-- (i.e. when the bytecodes were produced,
 					--	 or the mod date on the files)
   linkableModule   :: Module,           -- ^ The linkable module itself
-  linkableUnlinked :: [Unlinked]        -- ^ Those files and chunks of code we have
-                                        -- yet to link
+  linkableUnlinked :: [Unlinked]
+    -- ^ Those files and chunks of code we have yet to link.
+    --
+    -- INVARIANT: A valid linkable always has at least one 'Unlinked' item.
+    -- If this list is empty, the Linkable represents a fake linkable, which
+    -- is generated in HscNothing mode to avoid recompiling modules.
+    --
+    -- XXX: Do items get removed from this list when they get linked?
  }
 
 isObjectLinkable :: Linkable -> Bool