Fixes a segfault with callbacks seen on Ubuntu 26#391
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romgrk merged 2 commits intoMay 30, 2026
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Fixes romgrk#390. Disclaimer: I used Claude to debug this. Claude failed twice but then got on the right path when I ran gdb and pin-pointed the line in function.cc where it happens. It then produced a patch that was much to large, including all its failed attempts before. Those changes may still have merit, but they weren't essential for fixing this, so I narrowed it down to what appears the essential change. Tested with both reported cases, which now work.
- needed in Ubuntu 26
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Jun 14, 2026
On libffi 3.4+ the executable trampoline is a separate memory mapping from the writable ffi_closure, so the closure pointer itself is not callable; passing it to C as the callback function pointer segfaults when the callback fires. This is reproducible on Ubuntu 26 (libffi 3.5) and matches the `node examples/glib-timeout.js` crash in the report. Pass g_callable_info_get_closure_native_address() instead of the raw closure. This re-applies #391, which was reverted in #393 because it broke startup — guarded here by falling back to the closure pointer when introspection returns NULL, so a callback pointer is never NULL at bootstrap. On platforms where the two addresses coincide (older libffi, or where the closure is already executable) the behavior is unchanged. Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Fixes #390.
Disclaimer: I used Claude to debug this. Claude failed twice but then got on the right path when I ran gdb and pin-pointed the line in function.cc where it happens. It then produced a patch that was much to large, including all its failed attempts before. Those changes may still have merit, but they weren't essential for fixing this, so I narrowed it down to what appears the essential change.
Tested with both reported cases, which now work.
PS: also updated the test cases to use the newly required parameter for
Gst.init.