[Antik-devel] Memory corruption when loading an SBCL core containing antik (patch included)

[James Wright]

Hi,

When I dump an SBCL core from an image that has antik loaded, I get a
memory corruption error when loading the core:
  *** glibc detected *** sbcl: free(): invalid pointer: 0x0808d588 ***
This happens even with a minimal project that does nothing but load
antik; I've attached a script to reproduce the problem.

I did some investigation, and it looks like the problem is the
`*formatting-test-grid*' variable in `format-grid.lisp'.  It contains
a list of grids, including some foreign arrays.  Presumably the
foreign pointers in these arrays will be pointing to random/unowned
memory when the core is loaded.  I've run into similar problems before
in my own code (attempting to dump a global `*rng*' variable that
contained a GSLL random number generator).

I've attached a patch that replaces the problem `defparameter' form
with a function instead.  I can't find any references to this variable
in the source tree, so I assume it's just there for manual testing.

Thanks,
      James
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