8 /* Section 4.3.8.1 (Input Layout Qualifiers) of the GLSL 1.50 spec says:
11 * "Within any shader, the first redeclarations of gl_FragCoord must appear
12 * before any use of gl_FragCoord."
14 * Tests using gl_FragCoord before the redeclaration.
19 vec4 p = gl_FragCoord;
20 layout(origin_upper_left, pixel_center_integer) in vec4 gl_FragCoord;