#version 450
#extension GL_EXT_scalar_block_layout : require
layout(local_size_x = 1) in;

struct Foo
{
	vec3 a;
};

layout(scalar, set = 0, binding = 0) buffer SSBOScalar
{
	Foo v[];
} buffer_scalar;

void main()
{
	buffer_scalar.v[1].a.y = 1.0;
}