[MLton] Re: [MLton-commit] r6978

[Matthew Fluet]

On Wed, 5 Nov 2008, Wesley Terpstra wrote:
> Ensure that the current thread's stack is traceable by the collector.
> It (might be) possible to pass an object to MLton.size that can reach the
> current thread. If we don't have a valid return address and an up-to-date
> used value for the stack, the collector will segfault tracing the stack.

Please test more thoroughly, and ensure that the
<>/regression/size.sml (and related) regression tests pass.  Currently:

[fluet at shadow temp]$ ../build/bin/mlton -type-check true -debug true size.sml
invalid transfer: CCall {args = (<GCState>, global_0),
                          func = {args = (GCState, Objptr (opt_23)),
                                  bytesNeeded = None,
                                  convention = cdecl,
                                  ensuresBytesFree = false,
                                  mayGC = false,
                                  maySwitchThreads = true,
                                  modifiesFrontier = false,
                                  prototype = {args = (CPointer, CPointer),
                                               res = Some Word64},
                                  readsStackTop = true,
                                  return = Word64,
                                  symbolScope = private,
                                  target = GC_size,
                                  writesStackTop = false},
                          return = Some L_0}
...
Rssa.typeCheck
[fluet at shadow temp]$ ../build/bin/mlton -type-check false -debug true size.sml
[fluet at shadow temp]$ ./size
size: gc/invariant.c:10: assertIsObjptrInFromSpace: Assertion `isObjptrInFromSpace (s, *opp)' failed.
Aborted
[fluet at shadow temp]$ ../build/bin/mlton -type-check false -debug false 
size.sml
[fluet at shadow temp]$ ./size
MLton bug: control shouldn't reach here
Please send a bug report to MLton at mlton.org.