fix(examples): don't unref the MainLoop in glib-timeout (#429)#431
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The example followed the C idiom of balancing g_main_loop_new() with g_main_loop_unref(), but node-gtk's boxed wrapper already owns that reference and releases it on GC. The explicit loop.unref() drops it a second time, and the resulting double-free of the GMainLoop corrupts the heap — which, with gi.startLoop() active, faults during node's loop teardown at process exit (SIGSEGV in uv_close). Verified on Ubuntu 26 (libffi 3.5): 30/30 runs crash with the unref, 0/30 without. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
This was referenced Jun 14, 2026
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Summary
Fixes the crash in
node examples/glib-timeout.jstracked by #429.The example balanced
new GLib.MainLoop()withloop.unref()(the C idiom). But node-gtk's boxed wrapper already owns that reference andg_main_loop_unref()s it on GC, so the explicitloop.unref()drops it a second time → double-free of theGMainLoop. Standalone that's only ag_main_loop_unref: ref_count > 0warning, but withgi.startLoop()active the heap corruption faults during Node's loop teardown at exit (SIGSEGV inuv_close).This removes the
loop.unref()(and fixes the stalecallback.jsheader).Verified on Ubuntu 26.04 (rootless podman; libffi 3.5.2 / gir 1.86.0 / glib 2.88 / node 22)
loop.unref())Full run is clean:
Run loop. → count 0..3 → Loop ran., exit 0.Note (separate, not in this PR)
This is a narrow fix for the example. The underlying hazard — node-gtk exposing C
ref()/unref()/free()on GC-owned boxed wrappers, so following normal C ownership idioms double-frees — is left as an open design question in #429.🤖 Generated with Claude Code