← WebKit Silent-Fix Report — 2026-W22

cdfa73fdc3  [JSC] DFG object allocation sinking shouldn't insert a check when given a PutByVal node

severity medium class TypeConfusion confidence 0.50 JSC DFG allocation sinking
Kai Tamkun Fri May 29 09:38:26 2026 -0700 full: cdfa73fdc391180a7fe3b00eb01dd1d2b410956a bug report ↗ view on GitHub ↗
Primitive: invalid exit state / graph in object allocation sinking
Triage note: Fixes DFG allocation-sinking exit-state clobberization and removes an over-strict validation rule, a JIT soundness area.

Security-relevant, below the exploitable-grade bar for a full root-cause writeup. The triage verdict is above; the side-by-side patch is below.

Before / after

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