CPU and GPU renders are different for a simple curve scene

[xiamengqi2012]

I tried to render the following simple scene with 50 straight curves side by side but found CPU and GPU renders are different. My CUDA version is 11.5.

Integrator "path"
    "integer maxdepth" [ 1 ]
LookAt 0 0 -6
    0 0 0
    0 1 0
Camera "perspective"
    "float fov" [ 18 ]
Sampler "halton"
    "integer pixelsamples" [ 64 ]
Film "rgb"
    "string filename" [ "1layer_back.png" ]
    "integer yresolution" [ 400 ]
    "integer xresolution" [ 400 ]
    "float iso" [ 110 ]
WorldBegin
AttributeBegin
    Material "hair"
        "float eta" [ 1.55 ]
        "float beta_n" [ 0.3 ]
        "float beta_m" [ 0.3 ]
        "float alpha" [ 0 ]
        "rgb sigma_a" [ 0 0 0 ]
    Include "scenes/hair50.pbrt"
AttributeEnd
AttributeBegin
    LightSource "point"
        "point3 from" [ 0 0 -1 ]
        "rgb I" [ 10 10 10 ]
AttributeEnd

CPU render

GPU render

[mmp]

Yep, this is a known discrepancy (for now at least). See issues #201 and #7. PRs are welcome if you're familiar with OptiX. :-)