Using texture sample values in a critical section of WGSL fragment shader

I am getting errors when using a variable that is dependent on the value of a texture sample in the critical section of my fragment shader.

From what I understand, one should not sample textures in the critical section of the code because of diverging paths. As a result, I moved the initialization of fragData to the beginning so getPBRColor() is outside of the critical section. But I think that because fragData is still dependent on color when I use it in the critical section it still suffers from the error. Is there no way to use the value of a sampled texture inside the critical section?

Edit: Ignore the actual usage of the aBuffer. The important part is that I cannot write the color into it.

struct FragData {
    color: vec4<f32>,
    depth: f32,
}

@group(0) @binding(0) var baseColorTexture: texture_2d<f32>;
@group(0) @binding(1) var baseColorSampler: sampler;

// Accumulation buffer that I want to write a fragment's color and depth to
@group(1) @binding(0) var<storage, read_write> aBuffer: array<FragData>;

// A lock for each pixel. Has byte size = resolution.x * resolution.y * sizeOf(u32)
@group(1) @binding(1) var<storage, read_write> spinLock: array<atomic<u32>>;

@fragment
fn_main(input: FragmentInput) {
    let color: vec4<f32> = getPBRColor(input) // samples baseColorTexture to get color
    let fragDepth = input.position.z;
    let fragData = FragData(color, fragDepth); // causes crash
    //let fragData = FragData(vec4(0.0f), fragDepth); // runs fine

    let pixelIndex = input.position.y * resolution.x + input.position.x

    var keepWaiting = true;
    while (keepWaiting) {
        // CRITICAL SECTION: Attempt to acquire the lock
        if (atomicCompareExchangeWeak(&spinLock[pixelIndex], 0u, 1u).exchanged) {
            // This will cause the error depending if fragData.color uses a sampled value or not
            aBuffer[pixelIndex] = fragData;
        
            // Release the lock
            atomicStore(&spinLock[pixelIndex], 0u);
            keepWaiting = false;
        }
    }
}

Resulting error: GLDRendererMetal command buffer completion error: Error Domain=MTLCommandBufferErrorDomain Code=1 "Discarded (victim of GPU error/recovery) (00000005:kIOGPUCommandBufferCallbackErrorInnocentVictim)" UserInfo={NSLocalizedDescription=Discarded (victim of GPU error/recovery) (00000005:kIOGPUCommandBufferCallbackErrorInnocentVictim)