C++: Compiler and Linker functionality

Question

I want to understand exactly which part of a program compiler looks at and which the linker looks at. So I wrote the following code:

#include          


        

Answer 1

Compiler checks that the source code is language conformant and adheres to the semantics of the language. The output from compiler is object code.

Linker links the different object modules together to form a exe. The definitions of functions are located in this phase and the appropriate code to call them is added in this phase.

The compiler compiles code in the form of translation units. It will compile all the code that is included in a source .cppfile,
DefinedIncorrectFunction() is defined in your source file, So compiler checks it for language validity.
NonDefinedFunction() does have any definition in the source file so the compiler does not need to compile it, if the definition is present in some other source file, the function will be compiled as a part of that translation unit and further the linker will link to it, if at linking stage the definition is not found by the linker then it will raise a linking error.