Introduce isBoxedTupleDataCon and use it to fix #18644

The code that converts promoted tuple data constructors to
`IfaceType`s in `GHC.CoreToIface` was using `isTupleDataCon`, which
conflates boxed and unboxed tuple data constructors. To avoid this,
this patch introduces `isBoxedTupleDataCon`, which is like
`isTupleDataCon` but only works for _boxed_ tuple data constructors.

While I was in town, I was horribly confused by the fact that there
were separate functions named `isUnboxedTupleCon` and
`isUnboxedTupleTyCon` (similarly, `isUnboxedSumCon` and
`isUnboxedSumTyCon`). It turns out that the former only works for
data constructors, despite its very general name! I opted to rename
`isUnboxedTupleCon` to `isUnboxedTupleDataCon` (similarly, I renamed
`isUnboxedSumCon` to `isUnboxedSumDataCon`) to avoid this potential
confusion, as well as to be more consistent with
the naming convention I used for `isBoxedTupleDataCon`.

Fixes #18644.

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler/GHC/Stg/Lint.hs b/compiler/GHC/Stg/Lint.hs
index 206dd39187..2ce2c9b4d1 100644
--- a/compiler/GHC/Stg/Lint.hs
+++ b/compiler/GHC/Stg/Lint.hs
@@ -164,7 +164,7 @@ lintStgRhs (StgRhsClosure _ _ _ binders expr)
         lintStgExpr expr
 
 lintStgRhs rhs@(StgRhsCon _ con args) = do
-    when (isUnboxedTupleCon con || isUnboxedSumCon con) $ do
+    when (isUnboxedTupleDataCon con || isUnboxedSumDataCon con) $ do
       opts <- getStgPprOpts
       addErrL (text "StgRhsCon is an unboxed tuple or sum application" $$
                pprStgRhs opts rhs)
@@ -182,7 +182,7 @@ lintStgExpr (StgApp fun args) = do
 lintStgExpr app@(StgConApp con args _arg_tys) = do
     -- unboxed sums should vanish during unarise
     lf <- getLintFlags
-    when (lf_unarised lf && isUnboxedSumCon con) $ do
+    when (lf_unarised lf && isUnboxedSumDataCon con) $ do
       opts <- getStgPprOpts
       addErrL (text "Unboxed sum after unarise:" $$
                pprStgExpr opts app)