Do not skip locals init in state machines #14984
Merged
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Fixes #13386.
The problem turned out not to be the
initobjforTaskAwaiter, but the fact that the code emitted by task builder relies on locals being initialized. Randomly initialized bool flags could result in semi-arbitrary code being executed, like an exception handler despite no exception being thrown.An alternative solution would have been to manually initialize every local used by the state machine in
MoveNext, enabling user code, which is inlined, to potentially benefit from no initialization.