SKIP: FAILED

#version 310 es
precision mediump float;

struct buf0 {
  float two;
};

vec4 tint_symbol = vec4(0.0f, 0.0f, 0.0f, 0.0f);
layout(binding = 0) uniform buf0_1 {
  float two;
} x_8;

vec4 x_GLF_color = vec4(0.0f, 0.0f, 0.0f, 0.0f);
void main_1() {
  float a = 0.0f;
  float b = 0.0f;
  float x_33 = tint_symbol.x;
  a = ddx(cos(x_33));
  float x_37 = x_8.two;
  b = mix(2.0f, x_37, a);
  bool tint_tmp = (b >= 1.899999976f);
  if (tint_tmp) {
    tint_tmp = (b <= 2.099999905f);
  }
  if ((tint_tmp)) {
    x_GLF_color = vec4(1.0f, 0.0f, 0.0f, 1.0f);
  } else {
    x_GLF_color = vec4(0.0f, 0.0f, 0.0f, 0.0f);
  }
  return;
}

struct main_out {
  vec4 x_GLF_color_1;
};

struct tint_symbol_4 {
  vec4 tint_symbol_2;
};

struct tint_symbol_5 {
  vec4 x_GLF_color_1;
};

main_out tint_symbol_1_inner(vec4 tint_symbol_2) {
  tint_symbol = tint_symbol_2;
  main_1();
  main_out tint_symbol_6 = main_out(x_GLF_color);
  return tint_symbol_6;
}

tint_symbol_5 tint_symbol_1(tint_symbol_4 tint_symbol_3) {
  main_out inner_result = tint_symbol_1_inner(tint_symbol_3.tint_symbol_2);
  tint_symbol_5 wrapper_result = tint_symbol_5(vec4(0.0f, 0.0f, 0.0f, 0.0f));
  wrapper_result.x_GLF_color_1 = inner_result.x_GLF_color_1;
  return wrapper_result;
}

layout(location = 0) out vec4 x_GLF_color_1;

void main() {
  tint_symbol_4 inputs;
  inputs.tint_symbol_2 = gl_FragCoord;
  tint_symbol_5 outputs;
  outputs = tint_symbol_1(inputs);
  x_GLF_color_1 = outputs.x_GLF_color_1;
}

Error parsing GLSL shader:
ERROR: 0:18: 'ddx' : no matching overloaded function found 
ERROR: 0:18: '' : compilation terminated 
ERROR: 2 compilation errors.  No code generated.