update to current master againwip/T13904

1 files changed, 20 insertions, 7 deletions

diff --git a/compiler/main/HeaderInfo.hs b/compiler/main/HeaderInfo.hs
index be38e53f3d..127cc6d911 100644
--- a/compiler/main/HeaderInfo.hs
+++ b/compiler/main/HeaderInfo.hs
@@ -18,6 +18,8 @@ module HeaderInfo ( getImports
 
 #include "HsVersions.h"
 
+import GhcPrelude
+
 import HscTypes
 import Parser           ( parseHeader )
 import Lexer
@@ -120,7 +122,8 @@ mkPrelImports this_mod loc implicit_prelude import_decls
 
       preludeImportDecl :: LImportDecl GhcPs
       preludeImportDecl
-        = L loc $ ImportDecl { ideclSourceSrc = NoSourceText,
+        = L loc $ ImportDecl { ideclExt       = noExt,
+                               ideclSourceSrc = NoSourceText,
                                ideclName      = L loc pRELUDE_NAME,
                                ideclPkgQual   = Nothing,
                                ideclSource    = False,
@@ -241,7 +244,8 @@ getOptions' dflags toks
               | IToptions_prag str <- getToken open
               , ITclose_prag       <- getToken close
               = case toArgs str of
-                  Left err -> panic ("getOptions'.parseToks: " ++ err)
+                  Left _err -> optionsParseError str dflags $   -- #15053
+                                 combineSrcSpans (getLoc open) (getLoc close)
                   Right args -> map (L (getLoc open)) args ++ parseToks xs
           parseToks (open:close:xs)
               | ITinclude_prag str <- getToken open
@@ -311,17 +315,15 @@ checkExtension dflags (L l ext)
 
 languagePragParseError :: DynFlags -> SrcSpan -> a
 languagePragParseError dflags loc =
-  throw $ mkSrcErr $ unitBag $
-     (mkPlainErrMsg dflags loc $
+    throwErr dflags loc $
        vcat [ text "Cannot parse LANGUAGE pragma"
             , text "Expecting comma-separated list of language options,"
             , text "each starting with a capital letter"
-            , nest 2 (text "E.g. {-# LANGUAGE TemplateHaskell, GADTs #-}") ])
+            , nest 2 (text "E.g. {-# LANGUAGE TemplateHaskell, GADTs #-}") ]
 
 unsupportedExtnError :: DynFlags -> SrcSpan -> String -> a
 unsupportedExtnError dflags loc unsup =
-  throw $ mkSrcErr $ unitBag $
-    mkPlainErrMsg dflags loc $
+    throwErr dflags loc $
         text "Unsupported extension: " <> text unsup $$
         if null suggestions then Outputable.empty else text "Perhaps you meant" <+> quotedListWithOr (map text suggestions)
   where
@@ -337,3 +339,14 @@ optionsErrorMsgs dflags unhandled_flags flags_lines _filename
             ErrUtils.mkPlainErrMsg dflags flagSpan $
                     text "unknown flag in  {-# OPTIONS_GHC #-} pragma:" <+> text flag
 
+optionsParseError :: String -> DynFlags -> SrcSpan -> a     -- #15053
+optionsParseError str dflags loc =
+  throwErr dflags loc $
+      vcat [ text "Error while parsing OPTIONS_GHC pragma."
+           , text "Expecting whitespace-separated list of GHC options."
+           , text "  E.g. {-# OPTIONS_GHC -Wall -O2 #-}"
+           , text ("Input was: " ++ show str) ]
+
+throwErr :: DynFlags -> SrcSpan -> SDoc -> a                -- #15053
+throwErr dflags loc doc =
+  throw $ mkSrcErr $ unitBag $ mkPlainErrMsg dflags loc doc