Substantial improvements to coercion optimisation

[ghc-hetmet.git] / compiler / basicTypes / SrcLoc.lhs

diff --git a/compiler/basicTypes/SrcLoc.lhs b/compiler/basicTypes/SrcLoc.lhs
index e213bef..1a01980 100644 (file)
--- a/compiler/basicTypes/SrcLoc.lhs
+++ b/compiler/basicTypes/SrcLoc.lhs
@@ -126,19 +126,19 @@ srcLocFile _other       = (fsLit "<unknown file")
 -- | Raises an error when used on a "bad" 'SrcLoc'
 srcLocLine :: SrcLoc -> Int
 srcLocLine (SrcLoc _ l _) = l
-srcLocLine _other        = panic "srcLocLine: unknown line"
+srcLocLine (UnhelpfulLoc s) = pprPanic "srcLocLine" (ftext s)
 
 -- | Raises an error when used on a "bad" 'SrcLoc'
 srcLocCol :: SrcLoc -> Int
 srcLocCol (SrcLoc _ _ c) = c
-srcLocCol _other         = panic "srcLocCol: unknown col"
+srcLocCol (UnhelpfulLoc s) = pprPanic "srcLocCol" (ftext s)
 
 -- | Move the 'SrcLoc' down by one line if the character is a newline,
 -- to the next 8-char tabstop if it is a tab, and across by one
 -- character in any other case
 advanceSrcLoc :: SrcLoc -> Char -> SrcLoc
 advanceSrcLoc (SrcLoc f l _) '\n' = SrcLoc f  (l + 1) 1
-advanceSrcLoc (SrcLoc f l c) '\t' = SrcLoc f  l ((((c `shiftR` 3) + 1)
+advanceSrcLoc (SrcLoc f l c) '\t' = SrcLoc f  l (((((c - 1) `shiftR` 3) + 1)
                                                   `shiftL` 3) + 1)
 advanceSrcLoc (SrcLoc f l c) _    = SrcLoc f  l (c + 1)
 advanceSrcLoc loc            _    = loc -- Better than nothing