#version 450 struct S1 { float a; int b; }; layout(location = 0) flat in S1 in1; layout(location = 2) flat in S1 in2; layout(location = 4) flat in int cond; layout(location = 0) out float outv; void fun1(){} void fun2(){} void main() { // glslang will only make OpSelect for very trivial looking expressions float f1 = 1.0; float f2 = 2.0; outv = cond < 8 ? f1 : f2; // in all versions ivec4 iv1 = ivec4(f1); ivec4 iv2 = ivec4(f2); outv *= (cond > 0 ? iv1 : iv2).z; // in all versions, but in 1.4 as scalar condition, not smeared ala mix() mat3 m1 = mat3(1.0); mat3 m2 = mat3(2.0); outv *= (cond < 20 ? m1 : m2)[2][1]; // in 1.4, but not before S1 fv = cond > 5 ? in1 : in2; // in 1.4, but not before outv *= fv.a; cond > 0 ? fun1() : fun2(); // not allowed by any version }