Meaning of 'debugging symbols' with respect to GDB

Wikipedia says:

A debug symbol is information that expresses which programming-language constructs generated a specific piece of machin开发者_开发知识库e code in a given executable module.

1. Any examples of what kind of programming-language constructs are used for the purpose?

2. What is the meaning of "constructs" in this context? Functions?

The programming language constructs reffered to are things like if statements, while loops, assignment statements, etc etc.

Debug symbols are usually files that map addresses of executable chunks of machine bytecode with the original source code file and line number they represent. This is what allows you to do things like put a breakpoint on an if statement, and have the machine stop when the execution reached that particular bit of bytecode.