SKIP: FAILED #version 310 es precision mediump float; uint x_1 = 0u; void main_1() { uint x_2 = x_1; return; } void tint_symbol(uint x_1_param) { x_1 = x_1_param; main_1(); } void main() { tint_symbol(uint(gl_SampleID)); return; } Error parsing GLSL shader: ERROR: 0:16: 'gl_SampleID' : required extension not requested: GL_OES_sample_variables ERROR: 0:16: '' : compilation terminated ERROR: 2 compilation errors. No code generated.