Make Val::to_raw a safe function
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This commit updates Wasmtime's core `Val::to_raw` function a safe function. This was previously marked as `unsafe` with documentation that the raw pointer could be invalid, but that's not a reason for the function itself to be `unsafe`. Usage of the returned value is still `unsafe`, but simply acquiring the value is not itself an unsafe operation. This additionally marks a number of GC-related `from_raw` functions as safe. Wasmtime's GC is safe in the face of heap corruption, so it's memory safe to pass in any 32-bit value. Documentation still indicates that panics are possible, however.
fitzgen
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Jul 24, 2025
bongjunj
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Oct 20, 2025
This commit updates Wasmtime's core `Val::to_raw` function a safe function. This was previously marked as `unsafe` with documentation that the raw pointer could be invalid, but that's not a reason for the function itself to be `unsafe`. Usage of the returned value is still `unsafe`, but simply acquiring the value is not itself an unsafe operation. This additionally marks a number of GC-related `from_raw` functions as safe. Wasmtime's GC is safe in the face of heap corruption, so it's memory safe to pass in any 32-bit value. Documentation still indicates that panics are possible, however.
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This commit updates Wasmtime's core
Val::to_rawfunction a safe function. This was previously marked asunsafewith documentation that the raw pointer could be invalid, but that's not a reason for the function itself to beunsafe. Usage of the returned value is stillunsafe, but simply acquiring the value is not itself an unsafe operation.This additionally marks a number of GC-related
from_rawfunctions as safe. Wasmtime's GC is safe in the face of heap corruption, so it's memory safe to pass in any 32-bit value. Documentation still indicates that panics are possible, however.