Godot 4.5-Beta1 to 4.5-RC2 crashes immediately when loading project

[Quantx]

Tested versions

• Reproducible in: v4.5.rc.custom_build.ee87ee833, 4.5-RC2, 4.5-RC1, 4.5-Beta7, 4.5-Beta6, 4.5-Beta5, 4.5-Beta4, 4.5-Beta3, 4.5-Beta2, 4.5-Beta1
• Not reproducible in: 4.4.1-Stable

System information

Godot v4.5-rc2 - Windows 10 (build 19045) - Multi-window, 2 monitors - Direct3D 12 (Forward+) - dedicated AMD Radeon RX 5700 XT (Advanced Micro Devices, Inc.; 32.0.21025.10016) - AMD Ryzen 9 7900X3D 12-Core Processor (24 threads) | Godot v4.5.rc (ee87ee8) - Ubuntu 24.04.2 LTS 24.04 on Wayland - X11 display driver, Multi-window, 1 monitor - Vulkan (Forward+) - integrated AMD Radeon Vega 10 Graphics (RADV RAVEN) - AMD Ryzen 7 3700U with Radeon Vega Mobile Gfx (8 threads) - 13.56 GiB memory

Issue description

Godot crashes immediately on loading project. Issue encountered on two unrelated systems running 4.5-RC2, one running Windows and the other Linux.

Godot Engine v4.5.rc.custom_build.ee87ee833 (2025-09-12 14:16:27 UTC) - https://godotengine.org
Vulkan 1.3.289 - Forward+ - Using Device #0: AMD - AMD Radeon Vega 10 Graphics (RADV RAVEN)

ERROR: FATAL: Index p_index = 4061 is out of bounds (count = 4061).
   at: operator[] (./core/templates/local_vector.h:199)

================================================================
handle_crash: Program crashed with signal 4
Engine version: Godot Engine v4.5.rc.custom_build (ee87ee8332280a45473e96cc5acf6d9dd6130292)
Dumping the backtrace. Please include this when reporting the bug on: https://github.com/godotengine/godot/issues
[1] /lib/x86_64-linux-gnu/libc.so.6(+0x45330) [0x79718d645330] (??:0)
[2] ./godot.linuxbsd.editor.x86_64(+0x3edaa10) [0x55fb9b55aa10] (/home/quantx/godot-engine/core/templates/local_vector.h:199 (discriminator 2))
[3] ./godot.linuxbsd.editor.x86_64(+0x484d380) [0x55fb9becd380] (/home/quantx/godot-engine/servers/audio/audio_stream.cpp:235)
[4] ./godot.linuxbsd.editor.x86_64(+0x249edef) [0x55fb99b1edef] (/home/quantx/godot-engine/core/object/ref_counted.h:119)
[5] ./godot.linuxbsd.editor.x86_64(+0x2544669) [0x55fb99bc4669] (/home/quantx/godot-engine/core/object/ref_counted.h:220)
[6] ./godot.linuxbsd.editor.x86_64(+0x25471a5) [0x55fb99bc71a5] (/home/quantx/godot-engine/core/object/ref_counted.h:135)
[7] ./godot.linuxbsd.editor.x86_64(+0x2548560) [0x55fb99bc8560] (/home/quantx/godot-engine/editor/inspector/editor_resource_preview.cpp:392)
[8] ./godot.linuxbsd.editor.x86_64(+0x2548bec) [0x55fb99bc8bec] (/usr/include/c++/13/bits/atomic_base.h:505)
[9] ./godot.linuxbsd.editor.x86_64(+0x518f485) [0x55fb9c80f485] (/home/quantx/godot-engine/core/os/thread.cpp:64)
[10] ./godot.linuxbsd.editor.x86_64(+0x5bc9da4) [0x55fb9d249da4] (thread.o:?)
[11] /lib/x86_64-linux-gnu/libc.so.6(+0x9caa4) [0x79718d69caa4] (??:0)
[12] /lib/x86_64-linux-gnu/libc.so.6(+0x129c3c) [0x79718d729c3c] (??:0)
-- END OF C++ BACKTRACE --
================================================================
Aborted (core dumped)

Steps to reproduce

Open the attached project, observe that Godot 4.5-RC2 immediately crashes.

Minimal reproduction project (MRP)

test.zip

[beicause]

More detailed call stack in dev build:

================================================================
handle_crash: Program crashed with signal 4
Engine version: Godot Engine v4.5.rc.custom_build (3618632314732eee4700086105a64f99131b49f5)
Dumping the backtrace. Please include this when reporting the bug on: https://github.com/godotengine/godot/issues
[1] /usr/lib/libc.so.6(+0x3e540) [0x7ffff7c3e540] (??:0)
[2] LocalVector<short, unsigned int, false, true>::operator[](unsigned int) (/home/luo/godot/core/templates/local_vector.h:199)
[3] void AudioStreamPlaybackWAV::decode_samples<unsigned char, false, false, true>(unsigned char const*, AudioFrame*, long&, signed char&, unsigned int, AudioStreamPlaybackWAV::IMA_ADPCM_State*, AudioStreamPlaybackWAV::QOA_State*) (/home/luo/godot/scene/resources/audio_stream_wav.cpp:187)
[4] AudioStreamPlaybackWAV::_mix_internal(AudioFrame*, int) (/home/luo/godot/scene/resources/audio_stream_wav.cpp:384)
[5] AudioStreamPlaybackResampled::mix(AudioFrame*, float, int) (/home/luo/godot/servers/audio/audio_stream.cpp:232)
[6] EditorAudioStreamPreviewPlugin::generate(Ref<Resource> const&, Vector2 const&, Dictionary&) const (/home/luo/godot/editor/inspector/editor_preview_plugins.cpp:670)
[7] EditorResourcePreviewGenerator::generate_from_path(String const&, Vector2 const&, Dictionary&) const (/home/luo/godot/editor/inspector/editor_resource_preview.cpp:73)
[8] EditorResourcePreview::_generate_preview(Ref<ImageTexture>&, Ref<ImageTexture>&, EditorResourcePreview::QueueItem const&, String const&, Dictionary&) (/home/luo/godot/editor/inspector/editor_resource_preview.cpp:202)
[9] EditorResourcePreview::_iterate() (/home/luo/godot/editor/inspector/editor_resource_preview.cpp:323)
[10] EditorResourcePreview::_thread() (/home/luo/godot/editor/inspector/editor_resource_preview.cpp:418)
[11] EditorResourcePreview::_thread_func(void*) (/home/luo/godot/editor/inspector/editor_resource_preview.cpp:137)
[12] Thread::callback(unsigned long, Thread::Settings const&, void (*)(void*), void*) (/home/luo/godot/core/os/thread.cpp:66)
[13] void std::__invoke_impl<void, void (*)(unsigned long, Thread::Settings const&, void (*)(void*), void*), unsigned long, Thread::Settings, void (*)(void*), void*>(std::__invoke_other, void (*&&)(unsigned long, Thread::Settings const&, void (*)(void*), void*), unsigned long&&, Thread::Settings&&, void (*&&)(void*), void*&&) (/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/15.2.1/../../../../include/c++/15.2.1/bits/invoke.h:63)
[14] std::__invoke_result<void (*)(unsigned long, Thread::Settings const&, void (*)(void*), void*), unsigned long, Thread::Settings, void (*)(void*), void*>::type std::__invoke<void (*)(unsigned long, Thread::Settings const&, void (*)(void*), void*), unsigned long, Thread::Settings, void (*)(void*), void*>(void (*&&)(unsigned long, Thread::Settings const&, void (*)(void*), void*), unsigned long&&, Thread::Settings&&, void (*&&)(void*), void*&&) (/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/15.2.1/../../../../include/c++/15.2.1/bits/invoke.h:98)
[15] void std::thread::_Invoker<std::tuple<void (*)(unsigned long, Thread::Settings const&, void (*)(void*), void*), unsigned long, Thread::Settings, void (*)(void*), void*> >::_M_invoke<0ul, 1ul, 2ul, 3ul, 4ul>(std::_Index_tuple<0ul, 1ul, 2ul, 3ul, 4ul>) (/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/15.2.1/../../../../include/c++/15.2.1/bits/std_thread.h:303)
[16] std::thread::_Invoker<std::tuple<void (*)(unsigned long, Thread::Settings const&, void (*)(void*), void*), unsigned long, Thread::Settings, void (*)(void*), void*> >::operator()() (/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/15.2.1/../../../../include/c++/15.2.1/bits/std_thread.h:310)
[17] std::thread::_State_impl<std::thread::_Invoker<std::tuple<void (*)(unsigned long, Thread::Settings const&, void (*)(void*), void*), unsigned long, Thread::Settings, void (*)(void*), void*> > >::_M_run() (/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/15.2.1/../../../../include/c++/15.2.1/bits/std_thread.h:255)
[18] /home/luo/godot/bin/godot.linuxbsd.editor.dev.x86_64.llvm(+0xc7ce974) [0x555561d22974] (msdf-error-correction.cpp:?)
[19] /usr/lib/libc.so.6(+0x969cb) [0x7ffff7c969cb] (??:0)
[20] /usr/lib/libc.so.6(+0x11aa0c) [0x7ffff7d1aa0c] (??:0)
-- END OF C++ BACKTRACE --
================================================================

[bruvzg]

Seems like it's reading the buffer directly after the end, not sure what's exactly wrong, but adding an extra sample to the buffer (probably is not a correct place to fix it) prevents the crash and WAV is playing:

diff --git a/scene/resources/audio_stream_wav.cpp b/scene/resources/audio_stream_wav.cpp
index 6ecf9992c0..cabcba1df6 100644
--- a/scene/resources/audio_stream_wav.cpp
+++ b/scene/resources/audio_stream_wav.cpp
@@ -616,7 +616,7 @@ Ref<AudioStreamPlayback> AudioStreamWAV::instantiate_playback() {
                uint32_t ffp = qoa_decode_header(data.ptr(), data_bytes, &sample->qoa.desc);
                ERR_FAIL_COND_V(ffp != 8, Ref<AudioStreamPlaybackWAV>());
                sample->qoa.frame_len = qoa_max_frame_size(&sample->qoa.desc);
-               int samples_len = (sample->qoa.desc.samples > QOA_FRAME_LEN ? QOA_FRAME_LEN : sample->qoa.desc.samples);
+               int samples_len = (sample->qoa.desc.samples > QOA_FRAME_LEN ? QOA_FRAME_LEN : sample->qoa.desc.samples) + 1;
                int dec_len = sample->qoa.desc.channels * samples_len;
                sample->qoa.dec.resize(dec_len);
        }

[zhangjiangen11]

#110497
Similar to my own issue, I've been troubleshooting these strange crashes for a while now, and they're all caused by multi-threaded loading, specifically multi-threaded material processing and ArrayMesh surface initialization, which calls material data, leading to memory out-of-bounds and wild pointer access.
Because EditorResourcePreview is a separate thread, it also involves multi-threaded loading issues.

[matheusmdx]

The regression started between 4.4 stable and 4.5 dev1, bisecting.

[matheusmdx]

Reverting pr #100652 fixes the issue. CC @DeeJayLSP

I also tested with other .wav files and i was unable to reproduce the bug, so seems to be something specifically with the file provided in the mrp.

---

@zhangjiangen11 I don't think your issue is related to this one as this issue is related to the audio import

[DeeJayLSP]

It seems to happen because the provided test.wav has a baked loop end offset right at the end of the file. And it only happens with QOA-compressed streams.

For now, I submitted bruvzg's suggestion. Shouldn't have any issue outside of this specific case other than 2 or 4 more bytes per stream playback added.

[Calinou]

I can confirm this on 4.5.rc 2b832e9 (Linux).