drawArrays buffer error on compiled opengl code

**Version of emscripten/emsdk:**
emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 4.0.7-git
clang version 21.0.0git
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: /opt/homebrew/Cellar/emscripten/4.0.7/libexec/llvm/bin

**Failing command line in full:**
```
git clone https://github.com/timhutton/opengl-canvas-wasm.git

cd opengl-canvas-wasm

emcc main.cpp -std=c++11 -s WASM=1 -s USE_SDL=2 -O3 -o index.js

python -m http.server 8888

```
Then open `localhost:8888`, the triangle is not normally shown, only a black rectangle is shown（`127.0.0.1:8888` will work normally)

**Full link command and output with `-v` appended:**
The following is shown in browser console
```
WebGL: INVALID_OPERATION: drawArrays: no buffer is bound to enabled attribute

_glDrawArrays @ index.js:1

WebGL: too many errors, no more errors will be reported to the console for this context.
```
If I visit this webpage from 127.0.0.1:8888, this error will not show up.

If I compile the OpenGL C++ code with older version emcc, this error will not show up.