)]}'
{
  "commit": "bbfbb2531cdf32fb65b8e3754e440f687df00767",
  "tree": "8962f975410a71c6aad96b34242c37b2b0de0740",
  "parents": [
    "a57023617dbcba31727211d312cec8835602894a"
  ],
  "author": {
    "name": "Thomas Lively",
    "email": "tlively@google.com",
    "time": "Wed Jul 29 20:57:16 2026"
  },
  "committer": {
    "name": "GitHub",
    "email": "noreply@github.com",
    "time": "Wed Jul 29 20:57:16 2026"
  },
  "message": "Fix unreachable br_on_cast parse bug (#8948)\n\nThe br_on_cast* family of instructions take input and output type\nimmediates. We do not store the input type in the IR, so IRBuilder has\nto check the type of the `ref` operand against the input type before the\ninput type is lost. For br_on_cast_desc_eq{_fail} instructions with\nunreachable descriptor operands, we had a bug that would allow us to pop\na `ref` operand with an incorrect type, which would then immediately\nfail that type check. This was incorrect because the unreachable `desc`\noperand should have created a polymorphic stack that allowed popping any\nvalid type. Fix the bug by threading the expected input type through\nIRBuilder to ChildTyper, where we can note the proper type constraint on\nthe `ref` operand.",
  "tree_diff": [
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      "new_id": "70613347acb453dad37f36dd45c02b050a35e9b3",
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      "new_path": "test/lit/basic/unreachable-br-on-cast-desc.wast"
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}