[Pkg-haskell-maintainers] Bug#714458: ghc-mod: Error:No entry for "target has .ident directive" in "/usr/lib/ghc/settings"

[Paolo Inaudi]

Package: ghc-mod
Version: 2.0.2-1
Severity: grave
Justification: renders package unusable

Dear Maintainer,
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Launching
ghc-mod check file.hs
produces the following output
Error:No entry for "target has .ident directive" in "/usr/lib/ghc/settings"

I've added the required entry, and also other two, at the end of the file. It
now looks like:

[("GCC extra via C opts", " -fwrapv"),
 ("C compiler command", "/usr/bin/gcc"),
 ("C compiler flags", " -fno-stack-protector  -Wl,--hash-size=31 -Wl,--reduce-
memory-overheads"),
 ("ar command", "/usr/bin/ar"),
 ("ar flags", "q"),
 ("ar supports at file", "YES"),
 ("touch command", "touch"),
 ("dllwrap command", "/bin/false"),
 ("windres command", "/bin/false"),
 ("perl command", "/usr/bin/perl"),
 ("target os", "OSLinux"),
 ("target arch", "ArchX86"),
 ("target word size", "4"),
 ("target has GNU nonexec stack", "True"),
 ("target has subsections via symbols", "False"),
 ("target has .ident directive", "True"),
 ("LLVM llc command","llc"),
 ("LLVM opt command","opt")
]

I've added the last three lines, due to followings requirements from ghc-mod.
now the above command reports

Bad interface file: /usr/lib/ghc/base-4.5.0.0/Prelude.hi    mismatched
interface file versions (wanted "7063", got "7041")

And I cannot go on with patching since I don't understand the error anymore.

I was using ghc-mod with emacs



-- System Information:
Debian Release: jessie/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: i386 (i686)

Kernel: Linux 3.2.0-4-686-pae (SMP w/1 CPU core)
Locale: LANG=it_IT.UTF-8, LC_CTYPE=it_IT.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages ghc-mod depends on:
ii  haskell-mode  2.8.0-2
ii  libc6         2.17-3
ii  libffi6       3.0.13-4
ii  libgmp10      2:5.1.2+dfsg-1

Versions of packages ghc-mod recommends:
ii  ghc  7.4.1-4+b1

ghc-mod suggests no packages.

-- no debconf information