-ddump-splices truncates Integer literals to Int literals

I trusted that the splice results shown by -ddump-splices were correct. They weren't, which caused me to waste a lot of time debugging my Template Haskell expressions when they were already correct.

$ ghc --version
The Glorious Glasgow Haskell Compilation System, version 8.4.3

Example program

{-# OPTIONS_GHC -ddump-splices #-}
{-# LANGUAGE TemplateHaskell #-}

module Main where

import Language.Haskell.TH.Syntax  (Lift(lift))

main = print ( $( lift (toInteger (maxBound :: Int) + 1) )
             , $( lift (minBound :: Int) )
             )

Output of runghc

Note that the output of the program on the bottom line below is correct. The two splice results shown by -ddump-splices incorrectly match each other:

Example.hs:8:19-56: Splicing expression
    lift (toInteger (maxBound :: Int) + 1) ======> -9223372036854775808
Example.hs:9:19-40: Splicing expression
    lift (minBound :: Int) ======> (-9223372036854775808)
(9223372036854775808,-9223372036854775808)

Trac metadata

Trac field	Value
Version	8.4.3
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture

changed milestone to %8.6.1

changed weight to 5

added Tbug Trac import labels

changed weight to 7

That indeed looks bad. I'm bumping up the priority because it surely can't be hard to find and fix. Is anyone up for that?

Trac metadata

Trac field	Value
Priority	normal → high

D5089 ought to do it.

Trac metadata

Trac field	Value
Differential revisions	- → D5089

mentioned in commit 7a3cda53

If it's not too late, this can be merged to 8.6.

added 1 deleted label

Trac metadata

Trac field	Value
Differential revisions	D5089 → D5089, D5151

mentioned in commit ecbe26b6

closed

Merged #15502 (closed) with 6cad8e31 and #15502 (closed) with 8344588e.

Trac metadata

Trac field	Value
Resolution	Unresolved → ResolvedFixed

removed 1 deleted label

added Phigh label

mentioned in commit 8344588e

mentioned in commit 6cad8e31