Geometry shader is passing for without in layout

Geometry shader is passing for without in layout

Here is my geometry shader without input layout
#version 150
layout( points, max_vertices = 1 ) out;
void main()
{
for( int i = 0; i < gl_in.length(); i++ )
{
vec4 vert = gl_in[ i ].gl_Position;
gl_Position = vert;
gl_PointSize = gl_in[ i ].gl_PointSize;
EmitVertex();
}
}
This shader is compiling successfully. As far as know, It should fail as
no input is given