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author | Simon Peyton Jones <simonpj@microsoft.com> | 2018-08-20 09:48:41 +0100 |
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committer | Simon Peyton Jones <simonpj@microsoft.com> | 2018-08-20 14:21:38 +0100 |
commit | 2dcebe69f07f9b4328bc3dc2131ccf2953ffa21b (patch) | |
tree | 2106ada6f22bd198dc1891f1283740d26bf4047d /compiler/main/DynFlags.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/DynFlags.hs')
-rw-r--r-- | compiler/main/DynFlags.hs | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/compiler/main/DynFlags.hs b/compiler/main/DynFlags.hs index 66c67c352e..0bb796bb82 100644 --- a/compiler/main/DynFlags.hs +++ b/compiler/main/DynFlags.hs @@ -244,7 +244,9 @@ import qualified EnumSet import GHC.Foreign (withCString, peekCString) import qualified GHC.LanguageExtensions as LangExt +#if defined(GHCI) import Foreign (Ptr) -- needed for 2nd stage +#endif -- Note [Updating flag description in the User's Guide] -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |