Bug#1069980: haskell-futhark FTBFS: Missing build dependency on alex

[Adrian Bunk]

Source: haskell-futhark
Version: 0.25.15-1
Severity: serious
Tags: ftbfs

https://buildd.debian.org/status/logs.php?pkg=haskell-futhark&ver=0.25.15-1

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CallStack (from HasCallStack):
  withMetadata, called at libraries/Cabal/Cabal/src/Distribution/Simple/Utils.hs:370:14 in Cabal-3.8.1.0:Distribution.Simple.Utils
Error: hlibrary.setup: The program 'alex' is required but it could not be
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