diff options
author | Simon Peyton Jones <simonpj@microsoft.com> | 2018-08-20 09:48:41 +0100 |
---|---|---|
committer | Simon Peyton Jones <simonpj@microsoft.com> | 2018-08-20 14:21:38 +0100 |
commit | 2dcebe69f07f9b4328bc3dc2131ccf2953ffa21b (patch) | |
tree | 2106ada6f22bd198dc1891f1283740d26bf4047d /compiler/llvmGen/LlvmCodeGen/CodeGen.hs | |
parent | a08b285f74cd49196feb0f819d70ad0508689da3 (diff) | |
download | haskell-wip/T13064.tar.gz |
Fix unused-import warningswip/T13064
This patch fixes a fairly long-standing bug (dating back to 2015) in
RdrName.bestImport, namely
commit 9376249b6b78610db055a10d05f6592d6bbbea2f
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date: Wed Oct 28 17:16:55 2015 +0000
Fix unused-import stuff in a better way
In that patch got the sense of the comparison back to front, and
thereby failed to implement the unused-import rules described in
Note [Choosing the best import declaration] in RdrName
This led to Trac #13064 and #15393
Fixing this bug revealed a bunch of unused imports in libraries;
the ones in the GHC repo are part of this commit.
The two important changes are
* Fix the bug in bestImport
* Modified the rules by adding (a) in
Note [Choosing the best import declaration] in RdrName
Reason: the previosu rules made Trac #5211 go bad again. And
the new rule (a) makes sense to me.
In unravalling this I also ended up doing a few other things
* Refactor RnNames.ImportDeclUsage to use a [GlobalRdrElt] for the
things that are used, rather than [AvailInfo]. This is simpler
and more direct.
* Rename greParentName to greParent_maybe, to follow GHC
naming conventions
* Delete dead code RdrName.greUsedRdrName
* Slightly change the spec of the unused function
HsImpExpr.ieLWrappedName, and use it in RnNames.findImportUsage
Diffstat (limited to 'compiler/llvmGen/LlvmCodeGen/CodeGen.hs')
-rw-r--r-- | compiler/llvmGen/LlvmCodeGen/CodeGen.hs | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/compiler/llvmGen/LlvmCodeGen/CodeGen.hs b/compiler/llvmGen/LlvmCodeGen/CodeGen.hs index 51de1f6850..7c6de7fe43 100644 --- a/compiler/llvmGen/LlvmCodeGen/CodeGen.hs +++ b/compiler/llvmGen/LlvmCodeGen/CodeGen.hs @@ -38,7 +38,6 @@ import Util import Control.Monad.Trans.Class import Control.Monad.Trans.Writer -import Data.Semigroup ( Semigroup ) import qualified Data.Semigroup as Semigroup import Data.List ( nub ) import Data.Maybe ( catMaybes ) |