Bug#964400: haskell-yesod-core: build fails on IPv6-only buildds

[Adrian Bunk]

Source: haskell-yesod-core
Version: 1.6.18-1
Severity: serious
Tags: ftbfs

https://buildd.debian.org/status/fetch.php?pkg=haskell-yesod-core&arch=i386&ver=1.6.18-1&stamp=1593282031&raw=0

...
Failures:

  test/YesodCoreTest/RawResponse.hs:63:9: 
  1) RawResponse works
       uncaught exception: IOException of type NoSuchThing
       Network.Socket.getAddrInfo (called with preferred socket type/protocol: AddrInfo {addrFlags = [AI_PASSIVE,AI_ADDRCONFIG], addrFamily = AF_UNSPEC, addrSocketType = Stream, addrProtocol = 0, addrAddress = <assumed to be undefined>, addrCanonName = <assumed to be undefined>}, host name: Just "127.0.0.1", service name: Just "0"): does not exist (Address family for hostname not supported)

  To rerun use: --match "/RawResponse/works/"

  test/YesodCoreTest/RawResponse.hs:89:5: 
  2) sendWaiResponse + responseStream
       uncaught exception: IOException of type NoSuchThing
       Network.Socket.getAddrInfo (called with preferred socket type/protocol: AddrInfo {addrFlags = [AI_PASSIVE,AI_ADDRCONFIG], addrFamily = AF_UNSPEC, addrSocketType = Stream, addrProtocol = 0, addrAddress = <assumed to be undefined>, addrCanonName = <assumed to be undefined>}, host name: Just "127.0.0.1", service name: Just "0"): does not exist (Address family for hostname not supported)

  To rerun use: --match "/sendWaiResponse + responseStream/"

  test/YesodCoreTest/RawResponse.hs:91:5: 
  3) sendWaiApplication + responseStream
       uncaught exception: IOException of type NoSuchThing
       Network.Socket.getAddrInfo (called with preferred socket type/protocol: AddrInfo {addrFlags = [AI_PASSIVE,AI_ADDRCONFIG], addrFamily = AF_UNSPEC, addrSocketType = Stream, addrProtocol = 0, addrAddress = <assumed to be undefined>, addrCanonName = <assumed to be undefined>}, host name: Just "127.0.0.1", service name: Just "0"): does not exist (Address family for hostname not supported)

  To rerun use: --match "/sendWaiApplication + responseStream/"

Randomized with seed 920512437

Finished in 0.0724 seconds
157 examples, 3 failures
Test suite tests: FAIL
Test suite logged to: dist-ghc/test/yesod-core-1.6.18-tests.log
1 of 2 test suites (1 of 2 test cases) passed.
make: *** [/usr/share/cdbs/1/class/hlibrary.mk:154: check-ghc-stamp] Error 1


See #962019 for a discussion of a similar bug.