Fix segfault in GC finalisers - #18
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| ] | ||
| match exprs with | ||
| | [] -> body | ||
| | [x] -> [%expr Vk__helpers.keep_alive [%e Exp.array [x]] [%e owner]; [%e body]] |
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Even a size-one array can be pick up the flotarray optimized layout. I would suggest to use a ref or a ( (), x) tuple.
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Does it matter if it does? The optimised layout only causes a problem if it treats non-floats as floats.
Probably there should be a function to say whether a type needs to be kept alive and we could use that to skip floats completely.
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Actually, there's no reason to wrap a single value in anything. I've updated the PR.
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When a C struct refers to other C memory, we need to keep the targets alive. This is done by attaching a finaliser to the OCaml value pointing at the first struct, where the finaliser holds an OCaml value that points at the targets. Previously, this was done using [| Obj.repr field1; Obj.repr field2 |]. However, this fails if `field1` is a float and `field2` isn't as OCaml will try to convert it to a float-array. This will cause a segfault. It now uses a tuple instead when there are multiple fields, and adds the missing `Sys.opaque_identity` (as suggested by Florian Angeletti). Fixes Octachron#17.
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When a C struct refers to other C memory, we need to keep the targets alive. This is done by attaching a finaliser to the OCaml value pointing at the first struct, where the finaliser holds an OCaml value that points at the targets.
Previously, this was done using
[| Obj.repr field1; Obj.repr field2 |]. However, this fails iffield1is a float andfield2isn't as OCaml will try to convert it to a float-array. This will cause a segfault.It now uses a tuple instead when there are multiple fields, and adds the missing
Sys.opaque_identity(as suggested by Florian Angeletti).The old code was also catching and ignoringAdded a comment about when this happens.Invalid_argument(6b636fb). I removed this as I don't think it can happen, and if it does we probably want to know about it.Fixes #17.