What is the significance of the inline keyword in the context of the linker and program module compilation?

The keyword inline in C/C++ indicates to the compiler that the function should ideally be embedded at the call site to avoid the overhead of a function call. This can improve performance by eliminating jumps and call stacks.

From the linker and build perspective:

• Functions declared as inline are usually defined in header files so that the compiler can see their body during the compilation of each module.
• The linker, during the linking process, combines all definitions, avoiding multiple definition errors thanks to special rules for inline.
• inline does not guarantee that the function will be embedded; it is only a recommendation to the compiler.

Example:

inline int add(int a, int b) {
    return a + b;
}

// Can be used in multiple files without conflicts