Debugging: set vmctx slot before top-of-function epoch yield point.#12664
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cfallin merged 1 commit intobytecodealliance:mainfrom Feb 25, 2026
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Epoch yields emit debug events, and the debug event handler can walk the stack and look at the instance associated with each frame, which requires `vmctx`. We weren't setting the `vmctx` slot until after the epoch check in the function preamble, exposing a null or uninitialized slot to the accessor. This PR fixes that by hoisting the initialization to the very top of the preamble.
alexcrichton
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Feb 25, 2026
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Epoch yields emit debug events, and the debug event handler can walk the stack and look at the instance associated with each frame, which requires
vmctx. We weren't setting thevmctxslot until after the epoch check in the function preamble, exposing a null or uninitialized slot to the accessor. This PR fixes that by hoisting the initialization to the very top of the preamble.