[project @ 2005-05-05 12:39:19 by simonpj]

Only compare hi-boot iface with mother module if there *is* an hi-boot iface

diff --git a/ghc/compiler/iface/TcIface.lhs b/ghc/compiler/iface/TcIface.lhs
index 5062fd9..3addc10 100644 (file)
--- a/ghc/compiler/iface/TcIface.lhs
+++ b/ghc/compiler/iface/TcIface.lhs
@@ -237,10 +237,19 @@ tcHiBootIface mod
        ; if not (isOneShot mode)
                -- In --make and interactive mode, if this module has an hs-boot file
                -- we'll have compiled it already, and it'll be in the HPT
+               -- 
+               -- We check wheher the interface is a *boot* interface.
+               -- It can happen (when using GHC from Visual Studio) that we
+               -- compile a module in TypecheckOnly mode, with a stable, 
+               -- fully-populated HPT.  In that case the boot interface isn't there
+               -- (it's been replaced by the mother module) so we can't check it.
+               -- And that's fine, because if M's ModInfo is in the HPT, then 
+               -- it's been compiled once, and we don't need to check the boot iface
          then do { hpt <- getHpt
                  ; case lookupModuleEnv hpt mod of
-                     Just info -> return (hm_details info)
-                     Nothing   -> return emptyModDetails }
+                     Just info | mi_boot (hm_iface info) 
+                               -> return (hm_details info)
+                     other -> return emptyModDetails }
          else do
 
        -- OK, so we're in one-shot mode.