Bug#786727: crashes with segfault when drawLineH is called

[John Millikin]

I've uploaded version 0.2.12 to Hackage and my site with a fix for this
crash. It replaces the c2hs-based setters with a plain call to a C
function, which handles the struct initialization.

Version 0.2.12 also has unrelated changes to add new functionality. If
you'd prefer to cherrypick the fixes for this bug, they are:

* b44ae6e41bab47442d6fad8871d3f4e6e705aa40 to fix the crash.
* 2ac5b471a5d9a242a7591e8611d6d6385cbb2a89 to fix the build in c2hs<=0.18.0

On Sat, Jun 6, 2015 at 6:49 PM, John Millikin <jmillikin at gmail.com> wrote:

> I've verified the crash occurs when building with c2hs-0.25.2, and does
> not occur when building with c2hs-0.18.2.
>
> The generated code for withGlyph in 0.18.2 is:
>
>         (\(CCharT ptr) val -> do {pokeByteOff ptr 0 (val::CULong)})
> (CCharT pBuf) cAttrs
>         (\(CCharT ptr) val -> do {pokeByteOff ptr 8 (val::(CWString))})
> (CCharT pBuf) (wordPtrToPtr (fromIntegral (ord char)))
>         io (CCharT pBuf)
>
> The generated code for withGlyph in 0.25.2 is:
>
>         (\(CCharT ptr) val -> do {pokeByteOff ptr 0 (val :: CULong)})
> (CCharT pBuf) cAttrs
>         (\(CCharT ptr) val -> do {copyArray (ptr `plusPtr` 8) (val ::
> (CWString)) 5}) (CCharT pBuf) (wordPtrToPtr (fromIntegral (ord char)))
>         io (CCharT pBuf)
>
> The 0.25.2 code is definitely not going to work.
>
> Looking through the c2hs changelog, there are a number of
> suspicious-sounding entries that could be related:
>
> * [0.21.1] Fix treatment of arrays within structs [#115]
> * [0.21.1] Add default marshallers for C types [#83]
> * [0.22.1] Default marshallers for Char types [#98]
> * [0.24.1] Arrays in structuress bug [#123]
>
> My recommendation is to revert to an older c2hs version, because any
> package that uses c2hs to set the contents of an array is likely to be
> silently broken right now.
>
> Some time in the next few days, I will build a bunch of c2hs binaries and
> run that crash test to see which version in particular needs to be ifdef'd
> in haskell-ncurses.
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.alioth.debian.org/pipermail/pkg-haskell-maintainers/attachments/20151013/5dd8d47a/attachment.html>