[ASDAlexander77]

Indexing a generic-class field of an imported class failed to lower. Found in Document.ts of the BrowserLib sources attached to #231. It is the SymbolCallInternal error listed there.

// node.ts
export class Node {
    get toStringTag(): string { return "Node"; }
    childNodes: Array<Node>;
    constructor() { this.childNodes = new Array<Node>(); }
}

// doc.ts, compiled on its own with --emit=obj
import { Node } from "./node";
export function at(n: Node, i: number): Node {
    return n.childNodes[i];   // error: failed to legalize operation 'ts.SymbolCallInternal'
}

Cause

When a file's discovery pass meets an import of a source file, mlirGenInclude compiles the imported file in full, both its discovery and its real pass. At that point theModule is the importer's discovery module, which is erased afterwards.

A generic class specialized there (Array<Node>, the type of childNodes) had its members generated into that throwaway module, but its processing state stayed set. When the importer's real pass reached Array<Node>, mlirGen(ClassLikeDeclaration) saw it as already processed and returned early. The module that used the class never got any of its members. The index access became a call to Array<Node>.get, a symbol the module did not have.

Temporary tracing showed the sequence. The specialization's real-pass generation (allowPartialResolve=0) ran inside module=discovery_module, and the later pass in the importer's own module found processing=11 and skipped it.

Non-generic classes never hit this, because they are regenerated every time. Only specializations have the early return.

Fix

• The actual fix: ClassInfo records the module its processing state was reached in (processingModule). A specialization is skipped only when it was processed in the current module; in another module it is generated again. Discovery (allowPartialResolve) keeps its own state, which is unchanged.
• Also changed: instantiateSpecializedClassType (both overloads) turns declarationMode off while it generates the specialization. The members are linkonce_odr and belong to every module that uses them. An importer should not rely on the imported module's object happening to keep the members it needs.

Tests

• New test-compile-import-specialization: a Tree class with a children: Box<Tree> field, where Box<T> has an indexer, imported and walked recursively through children[i]. It uses a user-defined generic because the suite runs without the default lib. It fails on main with the same SymbolCallInternal error.
• Full release suite: 2988/2988 passed.
• TypeScriptCompilerDefaultLib tests, release jit and compile: 156/156 each.

Not in this PR

The same test through a -shared library (test-compile-shared-… / test-jit-shared-…) fails on main with generic type Box can't be found. The importer cannot name a generic class declared in the library it imports. That is a separate gap, so only the static variant is registered.

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