SKIP: FAILED #version 310 es precision mediump float; int x_1 = 0; void main_1() { int x_2 = x_1; return; } struct tint_symbol_2 { uint x_1_param; }; void tint_symbol_inner(uint x_1_param) { x_1 = int(x_1_param); main_1(); } void tint_symbol(tint_symbol_2 tint_symbol_1) { tint_symbol_inner(tint_symbol_1.x_1_param); return; } void main() { tint_symbol_2 inputs; inputs.x_1_param = uint(gl_SampleID); tint_symbol(inputs); } Error parsing GLSL shader: ERROR: 0:27: 'gl_SampleID' : required extension not requested: GL_OES_sample_variables ERROR: 0:27: '' : compilation terminated ERROR: 2 compilation errors. No code generated.