Method visitLet

src/ast/ast_escape_analysis.cpp:295–313

            return Visitor::visit(block);
        }
        virtual VariablePtr visitLet ( ExprLet * expr, const VariablePtr & var, bool last ) override {
            if ( var->does_not_escape && !blocks.empty() ) {
                // put the pointee in the stack frame instead of the heap; idempotent so the
                // notInferred re-infer loop terminates once the flag is already set
                if ( forceStack && setAllocateOnStack(var->init) ) {
                    anyWork = true;
                    func->notInferred();
                }
                // emit the scope-free only when it frees something real: a heap shell (not stack-
                // allocated) or owned heap members (arrays/tables) inside the pointee. a stack-
                // allocated POD frees nothing, so skip it - else every scope pays an interop call.
                bool stacked = forceStack && initIsAllocatedOnStack(var->init);
                bool ownsHeap = !( var->type->firstType && var->type->firstType->isNoHeapType() );
                if ( !stacked || ownsHeap ) {
                    pending.push_back({var, blocks.back()});
                }
            }
            return Visitor::visitLet(expr,var,last);
        }
        void emitScopeFree ( ExprBlock * block, Variable * var ) {
            if ( var->type->firstType->getSizeOf64() > 0x7fffffffull ) return;  // skip pointees over the 2^31 (32-bit) size limit - oversized/invalid types that error out anyway
            anyWork = true;