Nvidia miscompiles the buffer increment

[AaronGhost]

Description

The following code containing an array copy and a conversion from a boolean to an integer crashes.

#version 450

layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;

layout(std430, binding = 0) buffer buffer_0 {
 int ext_4[3]; // 1 1 1
};

void main()
{
 bool var_0[6] = bool[6](true, true, true, true, false, true);
 int var_1[3] = ext_4; // 1 1 1
 ++ ext_4[int(var_0[var_1[1]]) % 3];
}

NVIDIA output:

buffer_0 3 2 1

Expected output:

buffer_0 1 2 1

Thinking process

• var_1[1] = 1
• var_0[var_1[1]] = var_0[1] = true
• int(var_0[var_1[1]]) = int(true) = 1
• ext_4[int(var_0[var_1[1]]) % 3] = ext_4[1]
• ++ ext_4[1] so ext_4[1] is set to 2

Code link

For the related code in the shadertrap test format, see: nvidia/miscompilation/shader17.shadertrap