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… build Restores TT chomp.t / directive.t / text.t "Can't call method clone on undef" that the earlier commit "drop asymmetric incref in RuntimeScalar.addToArray" exposed — without reintroducing the DBIC TxnScopeGuard #18 refcount leak. ## Root cause During `my $arr = [ Foo->new(1), Foo->new(2) ]`: 1. Foo->new(1) returns a RuntimeScalar referencing a blessed hash. It's added to the literal's RuntimeArray. 2. Foo->new(2) constructs its value. Somewhere inside, `setLarge*` triggers MortalList.flush() to process pending deferred decrefs. 3. If the Foo(1) element is marked as mortal pending and hasn't yet been tied down by createReferenceWithTrackedElements (which runs only at literal-end), the mid-build flush decrements its refCount to 0 and fires DESTROY on Foo(1). 4. The anon-array-literal ends up with a DESTROYed Foo(1) — later accesses fail with "Can't call method X on undefined". ## Previous (incorrect) approach c8f669b solved this by adding a refcount-incref to every RuntimeScalar.addToArray call. The incref PINS each element so the mid-build flush can't drop refCount to 0. Unfortunately the incref also applies to paths that are NOT anon-array-literal construction — e.g. RuntimeList iteration used by some arg-flattening paths — and no matching decref exists, leaking +1 refCount per blessed value. That phantom refCount broke DBIC's zombie-ref double-DESTROY detection (t/storage/txn_scope_guard.t test 18). ## New approach: narrow envelope at the emit site Wrap the *entire* anon-array-literal construction in MortalList.suppressFlush(true) ... suppressFlush(prev); if (prev) flush(). Keeps the window of "mid-build flush cannot fire" as short as possible, and affects *only* the anon-array-literal call site (EmitLiteral), not every addToArray caller. Refcount accounting in every other path stays symmetric — DBIC's zombie-refs test keeps passing. Bytecode emitted (prolog): ICONST_1 INVOKESTATIC MortalList.suppressFlush(Z)Z ISTORE wasFlushingSlot <... existing element-add loop + createReferenceWithTrackedElements ...> Bytecode emitted (epilog, keeping the reference on TOS): ILOAD wasFlushingSlot INVOKESTATIC MortalList.suppressFlush(Z)Z POP ILOAD wasFlushingSlot IFNE skipFlush INVOKESTATIC MortalList.flush()V skipFlush: The IFNE ensures we don't flush when flushing was previously suppressed by an OUTER context — in that case the outer unwinder will handle it. ## Test plan - make dev — PASS - DBIC 15-test indicator set — **15/15 PASS (0 real failures)** - Template t/chomp.t — 78/78 PASS (was "Can't call method clone on undef" after the revert) - DBIC t/storage/txn_scope_guard.t — 18/18 PASS Generated with [Devin](https://cli.devin.ai/docs) Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
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