Hi,

I had been working on a CPP code for sometime now, without being aware that some parts of its code, especially security related were not being compiled.

Problem was like my product did not work for SSL mode. On analysis, I found that some part of CPP codes inside a switch(ENABLE_SSL_LIBRARY)were not getting compiled at all. And also that this gets set when we do newgrp crypto command on the box.

This left me without lots of doubts. I wanted to understand how these switches work and if this switch was propreitary to my code or something related to Linux.

My questions now are:

1. Switches like the one mentioned above , are they user defined, for my particular code or are they related to Linux/GCC or makefiles?

2.If a user can define such switches to control code compilation, then need to know the concepts/procedures behind it. How is it done ?

Kindly excuse if these are very very basic. But since I could not get proper stuffs on google, I thought I should ask some experts here who could either explain me or point me to appropriate resources (links of articles / tutorials)

Is that a switch like the C control structure switch? I would guess that the compiler can figure out the value of ENABLE_SSL_LIBRARY at compile time so it decides that some cases of the switch will never be taken and they don't need to be compiled. Hard to say for sure without more context. gcc will warn about such cases if you pass the -Wunreachable-code option to it.

What does "this" refer to here?