# RESOLVED — 0130: `#library` declared behind two aliased imports is dropped — no `-l` flag, no JIT dlopen

> **RESOLVED** (2026-06-12). Root cause as filed: `extractLibraries`
> and `extractFrameworks` (src/main.zig) walked the merged root's
> decls plus exactly ONE `namespace_decl` level, while aliased imports
> nest namespaces arbitrarily deep — a `#library`/`#framework` two or
> more aliases down never reached the AOT link args or the JIT dlopen
> loop. Both walks are now recursive over `namespace_decl` children
> (same `seen`-set dedup as before). Regression test:
> `examples/1617-modules-library-nested-namespace.sx` (+ its module
> dir) — `main → b :: #import → c :: #import` where c.sx declares
> `#library "pcap"`; libpcap is NOT in the compiler process's loaded
> images (unlike libz/libbz2/libsqlite3, which CoreServices/LLVM pull
> in and which mask the bug under `sx run`), so the pre-fix JIT fails
> symbol materialization and the pre-fix AOT link dies with undefined
> `_pcap_lib_version`. Gates: zig build test 426/426,
> tests/run_examples.sh 605/605, distribution repo `make test` 21/21
> at its HEAD plus a successful `make build` of its P5.2 branch state
> (dist.sx → ops → db → sqlite, the original failing chain).

## Symptom

A `#library` declaration in a module that is reached through TWO (or
more) levels of aliased `#import` never makes it into the build's
library list: `sx build` emits no `-l<name>` on the link line (link
fails with `Undefined symbols` for every `extern` fn of that
library), and `sx run` skips the dlopen of that library (the JIT then
resolves the extern symbol only if some already-loaded image happens
to export them).

- Observed: `main → b :: #import "b.sx" → c :: #import "c.sx"` where
  c.sx declares `zlib :: #library "z"` → link line ends `-lc` (no
  `-lz`), `ld: symbol(s) not found: _zlibVersion`.
- Expected: every `#library` reachable through the import graph is
  linked (AOT) / dlopened (JIT), regardless of import depth or
  aliasing.
- Control: aliasing c.sx DIRECTLY from main (one namespace level)
  produces `-lz` and links fine. A plain (unaliased) `#import` of c.sx
  from a module that main aliases also works — the merged decls sit at
  one namespace level.

## Reproduction

Three files in one directory; build `a.sx`.

```sx
// c.sx — declares the library + a extern fn
#import "modules/std.sx";

zlib :: #library "z";
zlibVersion :: () -> ?cstring extern zlib "zlibVersion";

zver :: () -> string {
    p := zlibVersion();
    if p == null { return ""; }
    return from_cstring(p!);
}
```

```sx
// b.sx — first namespace level
#import "modules/std.sx";
c :: #import "c.sx";

ver_via_b :: () -> string { return c.zver(); }
```

```sx
// a.sx — main; c.sx's library now sits two namespace levels deep
#import "modules/std.sx";
b :: #import "b.sx";

main :: () -> i32 {
    print("zlib {}\n", b.ver_via_b());
    return 0;
}
```

```
$ sx build -o a a.sx
Undefined symbols for architecture arm64:
  "_zlibVersion", referenced from: ...
error: linking failed
```

Replacing a.sx's import with `c :: #import "c.sx"` (and calling
`c.zver()` directly) links and prints the zlib version — same code,
one namespace level less.

Found in the distribution repo the first time a product chain nested
the SQLite bindings two aliases deep: `dist.sx → ops :: #import
"release/ops.sx" → db :: #import "../repo/db.sx" → #import
"../db/sqlite.sx"` loses `-lsqlite3` even though the bindings compile
fine (the extern wrappers ARE in main.o; only the link flag is gone).

## Investigation prompt

> In /Users/agra/projects/sx: `extractLibraries` (src/main.zig, ~line
> 877) walks `root.data.root.decls` and exactly ONE level of
> `namespace_decl` children. Aliased imports lower to nested
> `namespace_decl` nodes, so a `#library` (or, same pattern,
> `#framework` — see `extractFrameworks` right below it, ~line 904)
> sitting two or more namespace levels deep is never collected. Both
> consumers are affected: the AOT link args (`link(...)` in
> src/target.zig receives this list) and the JIT dlopen loop
> (src/main.zig ~line 274). Fix: make the walk recursive over
> `namespace_decl` (a small explicit stack or recursive helper over
> `ns.decls`), dedup as today via the `seen` set; apply the same to
> `extractFrameworks`. Verify with the three-file libz repro from
> issues/0130-library-decl-nested-namespace-dropped.md: `sx build`
> must emit `-lz` and link, `sx run` must dlopen libz; add an
> examples/ regression mirroring the repro (one library decl behind
> two aliased imports) that fails on pre-fix master. Then re-run the
> distribution repo's `make test` (which now links SQLite through
> dist.sx's ops→db→sqlite chain) to confirm the original failure is
> gone.
