7 // From section 4.3.7 (Interface Blocks) of the GLSL 1.50 spec:
9 // If an instance name (instance-name) is not used, the names
10 // declared inside the block are scoped at the global level and
11 // accessed as if they were declared outside the block.
13 // Consequently, inside an interface block lacking an instance-name,
14 // it is illegal to use a name that was previously declared inside a
15 // different interface block lacking an instance-name (just as it
16 // would be illegal to redeclare the name outside an interface block).