Segfault when reloading VST on linux

[alec-deason]

I'm seeing segfaults when I reload a vst built with vst-rs. I can reproduce the behavior with the sine_synth example hosted in Carla:

To reproduce: Build the example and copy the so to your vst directory Open Carla and load the vst copy the so into the vst directory again, replacing the file Carla segfaults with the following trace:

Thread 18 "carla" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fffa9363640 (LWP 1260517)]
0x000000000000ed40 in ?? ()
(gdb) bt
#0  0x000000000000ed40 in  ()
#1  0x00007fffd4019d56 in vst::interfaces::process_replacing
    (effect=0x555556971f70, raw_inputs=0x7fffa9362b20, raw_outputs=0x555556971f50, samples=1024)
    at /home/alec/Code/Vendor/vst-rs/src/interfaces.rs:32
#2  0x00007fffea511013 in  () at /usr/lib/carla/libcarla_standalone2.so
#3  0x00007fffea5197da in  () at /usr/lib/carla/libcarla_standalone2.so
#4  0x00007fffea4898f0 in  () at /usr/lib/carla/libcarla_standalone2.so
#5  0x00007fffea489d76 in  () at /usr/lib/carla/libcarla_standalone2.so
#6  0x00007fffea184230 in  () at /usr/lib/libjack.so.0
#7  0x00007fffea183ef8 in  () at /usr/lib/libjack.so.0
#8  0x00007fffea1a08fd in  () at /usr/lib/libjack.so.0
#9  0x00007ffff79e7299 in start_thread () at /usr/lib/libpthread.so.0
#10 0x00007ffff7afe053 in clone () at /usr/lib/libc.so.6

I see what appears to be the same segfault when hosting plugins in Reaper as well.

I'm on Arch linux and commit a39869 of vst-rs