Bug#899208: pandoc: FTBFS on armel/armhf: Identifier `InvalidYaml' used as a constructor-like thing

[John MacFarlane]

I don't understand this error.  InvalidYaml *is* a constructor for the
type ParseException in Data.Yaml (yaml package).  So it's not clear why
the compiler would complain about it being used as a "constructor-like
thing."

What version of ghc is being used to compile?

What version of the Haskell yaml package is being used?

Emilio Pozuelo Monfort <pochu at debian.org> writes:

> Source: pandoc
> Version: 2.2-1
> Severity: serious
>
> pandoc fails to build on armel and armhf:
>
> [117 of 131] Compiling Text.Pandoc.Readers.Markdown ( src/Text/Pandoc/Readers/Markdown.hs, dist-ghc/build/Text/Pandoc/Readers/Markdown.o )
>
> src/Text/Pandoc/Readers/Markdown.hs:275:20: error:
>     * Identifier `InvalidYaml' used as a constructor-like thing
>     * In the pattern:
>         InvalidYaml (Just YamlParseException {yamlProblem = problem,
>                                               yamlContext = _ctxt,
>                                               yamlProblemMark = YamlMark {yamlLine = yline,
>                                                                           yamlColumn = ycol}})
>       In a case alternative:
>           InvalidYaml (Just YamlParseException {yamlProblem = problem,
>                                                 yamlContext = _ctxt,
>                                                 yamlProblemMark = YamlMark {yamlLine = yline,
>                                                                             yamlColumn = ycol}})
>             -> logMessage
>                  $ CouldNotParseYamlMetadata
>                      problem
>                      (setSourceLine
>                         (setSourceColumn pos (sourceColumn pos + ycol))
>                         (sourceLine pos + 1 + yline))
>       In a stmt of a 'do' block:
>         case err' of
>           InvalidYaml (Just YamlParseException {yamlProblem = problem,
>                                                 yamlContext = _ctxt,
>                                                 yamlProblemMark = YamlMark {yamlLine = yline,
>                                                                             yamlColumn = ycol}})
>             -> logMessage
>                  $ CouldNotParseYamlMetadata
>                      problem
>                      (setSourceLine
>                         (setSourceColumn pos (sourceColumn pos + ycol))
>                         (sourceLine pos + 1 + yline))
>           _ -> logMessage $ CouldNotParseYamlMetadata (show err') pos
>     |
> 275 |                    InvalidYaml (Just YamlParseException{
>     |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^...
>
>
> Full logs at https://buildd.debian.org/status/package.php?p=pandoc&suite=sid
>
> Emilio
>
> -- System Information:
> Debian Release: buster/sid
>   APT prefers unstable
>   APT policy: (800, 'unstable'), (700, 'experimental'), (650, 'testing'), (500, 'unstable-debug'), (500, 'testing-debug')
> Architecture: amd64 (x86_64)
> Foreign Architectures: i386, armhf
>
> Kernel: Linux 4.16.0-1-amd64 (SMP w/4 CPU cores)
> Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8), LANGUAGE=en_GB.utf8 (charmap=UTF-8)
> Shell: /bin/sh linked to /bin/dash
> Init: systemd (via /run/systemd/system)
> LSM: AppArmor: enabled