Fix crash lowering a global const object literal with a mutating method - #246
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The #246 isBoundMethodTupleConstant special case in GlobalOpLowering decided whether a global's initializer needs the constructor path based on whether any ConstantOp in it had a bound-method-shaped tuple field. Since PR #249 boxes every method-bearing object literal, such a literal's initializer always contains a NewOp (the boxing recipe), which the walk's existing NewOp case already forces onto the constructor path -- making the bound-method check redundant. Verified via a diagnostic probe at that call site across every test file (zero hits) before removing it for real. Investigated but did NOT remove needsIdentityStorage/boundRefMaterializedCache: contrary to the original plan (docs/object-literal-boxing-design.md), these are still load-bearing. Whenever a boxed literal is unboxed back into a plain tuple to match a declared/inferred type (annotated const, parameter, interface-cast fallback, generic intersection/inference), the resulting tuple's method field is still bound-method-shaped even though the tuple itself is a plain value -- that machinery is what makes calling through it work correctly instead of crash. Root-caused via site-tagged diagnostic probes across the full test corpus; documented in the design doc so this isn't re-attempted without re-deriving the same finding. Full suite green: 353/353 JIT + 357/357 AOT. Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
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Summary
const obj = { ..., method() { this.x = ... } }crashed the compiler (0xC0000005) at JIT materialization time.letat global scope andconstdeclared locally inside a function were both unaffected, which is why this went unnoticed until now.GlobalOpLoweringdecides whether a global needs a runtime constructor function or can be a plain static LLVMconstantinitializer by walking its initializer region against a fixed allowlist of op kinds — but had no case for aConstantOpwhoseTupleType/ConstTupleTyperesult has a bound-method field. Such a field lowers viaLLVM::AddressOfOp+LLVM::InsertValueOp(LLVMCodeHelper::getTupleFromArrayAttr), which is not valid inside a static global initializer region — only inside real code (a function) — so the global ended up with a corrupted struct layout and crashed on the first indirect call through it.TupleType/ConstTupleTypeconstants with a bound-method field (MLIRTypeHelper::hasBoundMethodField, from Give const bindings with bound-method fields (generators) real identity storage #244), not "any constant referencing a symbol." An earlier, broader attempt keyed on "does the constant's attribute contain aFlatSymbolRefAttranywhere" also caught MSVC RTTI/EH type-descriptor globals (e.g.??_R0PEAD@8, which reference thetype_infovtable symbol) that were already lowering correctly as static data — forcing those through the constructor path broke JIT symbol materialization for the whole module. That regression was caught and fixed before this PR by narrowing the check to the type-based predicate.Test plan
constobject with a mutating method) now runs cleanlytest/tester/tests/00global_const_object_method.ts(compile + JIT)00try_finally_break_continueand 11 others) is resolved🤖 Generated with Claude Code