Key each foreach step to its activation so generator instances don't … - #382
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…clash foreach iteration state lives in ph7_foreach_info.aStep, a per-STATEMENT stack shared by every activation, and OP_FOREACH_STEP peeked the last entry. Two suspended activations of the same textual foreach — two generator instances, two fibers, or a recursive call paused in the same loop — resume out of LIFO order and grab each other's step, so $g1 = g([1,2,3]); $g2 = g([10,20]) with interleaved next()/current() printed 11020 where php prints 110220 (a silent wrong answer). Record the owning activation frame on each step (ph7_foreach_step.pFrame, normalized past exception frames via VmSkipExceptionFrames, stamped at OP_FOREACH_INIT). OP_FOREACH_STEP now scans aStep top-down for the step whose pFrame matches the running activation — the most-recent push wins, so a leaked step that shares a recycled frame address never shadows the live one. The step teardown paths remove by pointer (new VmForeachStepUnlink) instead of popping the tail, order-preserving so a live step is never reordered below a leaked sibling. This mirrors the per-exec-context cursor the yield-from opcode already keeps for delegation. Byte-verified vs php 8.5.7 across two-instance, recursive, two-fiber, nested-in-generator, and break-leak-interleave scenarios; cross-engine test foreach_same_generator_two_instances; test-compat green; docker ASan+UBSan clean; full and tiny builds warning-free.
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Details: https://github.com/alganet/PHL/actions/runs/30112170816 |
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…clash
foreach iteration state lives in ph7_foreach_info.aStep, a per-STATEMENT stack shared by every activation, and OP_FOREACH_STEP peeked the last entry. Two suspended activations of the same textual foreach — two generator instances, two fibers, or a recursive call paused in the same loop — resume out of LIFO order and grab each other's step, so $g1 = g([1,2,3]); $g2 = g([10,20]) with interleaved next()/current() printed 11020 where php prints 110220 (a silent wrong answer).
Record the owning activation frame on each step (ph7_foreach_step.pFrame, normalized past exception frames via VmSkipExceptionFrames, stamped at OP_FOREACH_INIT). OP_FOREACH_STEP now scans aStep top-down for the step whose pFrame matches the running activation — the most-recent push wins, so a leaked step that shares a recycled frame address never shadows the live one. The step teardown paths remove by pointer (new VmForeachStepUnlink) instead of popping the tail, order-preserving so a live step is never reordered below a leaked sibling. This mirrors the per-exec-context cursor the yield-from opcode already keeps for delegation.
Byte-verified vs php 8.5.7 across two-instance, recursive, two-fiber, nested-in-generator, and break-leak-interleave scenarios; cross-engine test foreach_same_generator_two_instances; test-compat green; docker ASan+UBSan clean; full and tiny builds warning-free.