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| 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/main/DynamicLoading.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/main/DynamicLoading.hs')
| -rw-r--r-- | compiler/main/DynamicLoading.hs | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/compiler/main/DynamicLoading.hs b/compiler/main/DynamicLoading.hs index 764bf2dd41..7420f7cc01 100644 --- a/compiler/main/DynamicLoading.hs +++ b/compiler/main/DynamicLoading.hs @@ -25,7 +25,6 @@ module DynamicLoading ( ) where import GhcPrelude -import HscTypes ( HscEnv ) import DynFlags #if defined(GHCI) @@ -63,6 +62,7 @@ import GHC.Exts ( unsafeCoerce# ) #else +import HscTypes ( HscEnv ) import Module ( ModuleName, moduleNameString ) import Panic @@ -76,12 +76,13 @@ import Control.Monad ( unless ) -- actual compilation starts. Idempotent operation. Should be re-called if -- pluginModNames or pluginModNameOpts changes. initializePlugins :: HscEnv -> DynFlags -> IO DynFlags -initializePlugins hsc_env df #if !defined(GHCI) +initializePlugins _ df = do let pluginMods = pluginModNames df unless (null pluginMods) (pluginError pluginMods) return df #else +initializePlugins hsc_env df | map lpModuleName (plugins df) == pluginModNames df -- plugins not changed && all (\p -> lpArguments p == argumentsForPlugin p (pluginModNameOpts df)) (plugins df) -- arguments not changed |