bug#11701: 24.1.50; SIGBUS in libMagickCore when reconverting pdf files in doc-view-mode

[Lars Ingebrigtsen]

Andreas Politz <politza@fh-trier.de> writes:

> When reverting a doc-view buffer, Emacs crashes receiving a SIGBUS error
> (below is a back-trace).  I am not able to reproduce it without loading
> my init file, but am able to reproduce it on a certain file constantly
> otherwise.
>
> The crash happens after doc-view deletes its cache files in
> `doc-view-reconvert-doc' and starts to convert the PDF pages to PNG
> files (and indirectly calling functions in the magick library).  It
> seems that the deleted file is still mmapped and accessed in the library
> at this point, leading to the error.
>
> A. Politz
>
> Program received signal SIGBUS, Bus error.
> 0x00007ffff44d99af in CopyMagickMemory () from /usr/lib/libMagickCore.so.3
> (gdb) quit[K(gdb) bt
> #0  0x00007ffff44d99af in CopyMagickMemory () from /usr/lib/libMagickCore.so.3
> #1  0x00007ffff4419704 in ReadBlob () from /usr/lib/libMagickCore.so.3
> #2  0x00007fffeb10068e in ?? () from 
> /usr/lib/ImageMagick-6.6.0/modules-Q16/coders/png.so

(I'm going through old bug reports that have unfortunately gotten no
responses yet.)

This crash wasn't handled at the time, and as this was reported more
than seven years ago, I don't think there's much chance of making any
progress here, so I'm closing this bug report.  If you're still seeing
similar crashes in modern Emacs versions, please reopen.

(And Emacs 27, by default, isn't built with ImageMagick support, so
these types of crashes are less likely now.)

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no