Crash in WebAssembly Instruction Selection

[rune-scape]

Version of emscripten/emsdk:

emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 4.0.22 (0f3d2e62bccf8e14497ff19e05a1202c51eb0c65)
clang version 22.0.0git (https:/github.com/llvm/llvm-project c7706d9472fe880ba1d3418919ad4185710c9559)
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: /mnt/cute/git/emsdk/upstream/bin

Failing command:

Stack dump:
0.      Program arguments: /mnt/cute/git/emsdk/upstream/bin/wasm-ld -o bin/godot.web.editor.wasm32.nothreads.rune-custom-4.5.wasm -mllvm -combiner-global-alias-analysis=false -mllvm -wasm-enable-sjlj -mllvm -disable-lsr -mllvm -exception-model=wasm /tmp/tmpb4ne5vrplibemscripten_js_symbols.so --export=free --export=malloc --export=_emscripten_stack_alloc --export=__funcs_on_exit --export=__wasm_call_ctors --export=_emscripten_stack_restore --export=emscripten_stack_get_current --export-if-defined=__start_em_asm --export-if-defined=__stop_em_asm --export-if-defined=__start_em_lib_deps --export-if-defined=__stop_em_lib_deps --export-if-defined=__start_em_js --export-if-defined=__stop_em_js --export-if-defined=main --export-if-defined=__main_argc_argv --export-if-defined=fflush --export-table -z stack-size=5242880 --max-memory=2147483648 --initial-memory=67108864 --no-entry --no-stack-first --table-base=1 --global-base=1024 -u _emscripten_run_callback_on_thread bin/obj/platform/web/audio_driver_web.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/platform/web/webmidi_driver.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/platform/web/display_server_web.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/platform/web/http_client_web.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/platform/web/javascript_bridge_singleton.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/platform/web/web_main.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/platform/web/ip_web.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/platform/web/net_socket_web.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/platform/web/os_web.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/platform/web/editor/web_tools_editor_plugin.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/platform/web/web_runtime.web.editor.wasm32.nothreads.rune-custom-4.5.o bin/obj/main/libmain.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodules.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_text_server_adv.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_fbx.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_gltf.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_ktx.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_svg.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_theora.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_vorbis.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_astcenc.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_basis_universal.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_bcdec.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_betsy.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_bmp.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_csg.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_cvtt.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_dds.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_enet.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_etcpak.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_gdscript.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_godot_physics_2d.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_godot_physics_3d.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_gridmap.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_hdr.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_interactive_music.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_jolt_physics.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_jpg.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_jsonrpc.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_lightmapper_rd.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_mbedtls.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_meshoptimizer.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_minimp3.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_mobile_vr.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_multiplayer.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_navigation_2d.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_navigation_3d.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_noise.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_ogg.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_regex.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_tga.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_tinyexr.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_upnp.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_vhacd.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_webp.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_webrtc.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_websocket.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_webxr.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_xatlas_unwrap.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/libmodule_zip.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/platform/libplatform.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/drivers/libdrivers.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/editor/libeditor.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/scene/libscene.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/servers/libservers.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/core/libcore.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/freetype/libfreetype_builtin.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/msdfgen/libmsdfgen_builtin.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/text_server_adv/libharfbuzz_builtin.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/text_server_adv/libgraphite_builtin.web.editor.wasm32.nothreads.rune-custom-4.5.a bin/obj/modules/text_server_adv/libicu_builtin.web.editor.wasm32.nothreads.rune-custom-4.5.a -L/mnt/cute/git/emsdk/upstream/emscripten/cache/sysroot/lib/wasm32-emscripten/lto -L/mnt/cute/git/emsdk/upstream/emscripten/src/lib -lGL-webgl2-ofb -lal -lhtml5 -lstubs -lc -ldlmalloc -lcompiler_rt-legacysjlj -lc++-noexcept -lc++abi-noexcept -lsockets
1.      Running pass 'Function Pass Manager' on module 'ld-temp.o'.
2.      Running pass 'WebAssembly Instruction Selection' on function '@_ZN23VariantUtilityFunctions23cubic_interpolate_angleEddddd'
#0 0x000056542276a998 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/mnt/cute/git/emsdk/upstream/bin/wasm-ld+0x1124998)
#1 0x00005654227676a5 llvm::sys::RunSignalHandlers() (/mnt/cute/git/emsdk/upstream/bin/wasm-ld+0x11216a5)
#2 0x000056542276b546 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
#3 0x00007efce499edf0 (/lib/x86_64-linux-gnu/libc.so.6+0x3fdf0)
#4 0x0000565422ceefd4 (/mnt/cute/git/emsdk/upstream/bin/wasm-ld+0x16a8fd4)

i was compiling my godot branch at https://github.com/rune-scape/godot/tree/rune-custom-4.5 with scons platform=web debug_symbols=yes threads=no target=editor prodection=yes optimize=size lto=full

[sbc100]

Because this is an LTO build the repro is likely to pretty large. Does the issue reproduce without LTO?

If LTO is the only way to reproduce, if will help if you can link with -Wl,-save-temps and then attach the resulting bitcode file.

[kleisauke]

Does this reproduce with Emscripten 4.0.21? It might be the same as issue reported in llvm/llvm-project#170719 (comment).

Edit: looking at https://github.com/godotengine/godot/blob/4.5.1-stable/core/math/math_funcs.h#L358-L371, this is likely the same issue.

[rune-scape]

Yes! it does not reproduce with 4.0.21! thank you! turning lto off did not seem to do anything, only debug optimization avoided this