Bad GLSL from shared term in conditional

[floybix]

Hi, I found this failure case. If a term appears multiple times within one branch of an if, the shared term gets emitted without an assignment to a variable.

(require '[gamma.api :as g])
(require '[gamma.program :as p])

(def ans2
  (let [g-elem (g/* 5 5)
        sh {(g/gl-position) (g/vec4 (g/if (g/== 0 0)
                                          (g/+ g-elem g-elem)
                                          0.0))}]
    (:glsl (p/shader sh {:float :highp}))))

(println ans2)

precision highp float;

void main(void){
float v387;
float v394;
if((0.0 == 0.0)){
  (5.0 * 5.0);                       <----- note missing assignment
  (v387 = (v394 + v394));}
  else {
    (v387 = 0.0);}
(gl_Position = vec4(v387));
}

I tried to track it down in the code but got lost in the compiler.