What is inline function?

An inline function is one for which the compiler copies the code from the function definition directly into the code of the calling function rather than creating a separate set of instructions in memory. This eliminates call-linkage overhead and can expose significant optimization opportunities.

Is it possible to have recursive inline function?

Inline functions can also be recursive. Since the call to an inline function is replaced with the function itself, the overhead of building a parameter list and calling the function is eliminated in the calling function. Below is an example of a program that calls an inline function.

What is inline function Kotlin?

An inline function is declare with a keyword inline. The use of inline function enhances the performance of higher order function. The inline function tells the compiler to copy parameters and functions to the call site. The virtual function or local function cannot be declared as inline.

Why Inline functions are used in C?

When functions are inlined, the compiler substitutes the function itself for the call of the function. This can speed up your software because you don’t waste time calling a function and then returning its values. You simply run the function in line with your code.

Can inline function contain static variables?

Static local variables are not allowed to be defined within the body of an inline function. C++ functions implemented inside of a class declaration are automatically defined inline.

What does-fno-gnu89-inline mean?

See An Inline Function is As Fast As a Macro . Using this option is roughly equivalent to adding the gnu_inline function attribute to all inline functions (see Function Attributes ). The option -fno-gnu89-inline explicitly tells GCC to use the C99 semantics for inline when in C99 or gnu99 mode (i.e., it specifies the default behavior).

What does the-fgnu89-inline option do?

The option -fgnu89-inline tells GCC to use the traditional GNU semantics for inline functions when in C99 mode. See An Inline Function is As Fast As a Macro . Using this option is roughly equivalent to adding the gnu_inline function attribute to all inline functions (see Function Attributes ).

How do I declare a function inline in GCC?

GCC implements three different semantics of declaring a function inline. One is available with -std=gnu89 or -fgnu89-inline or when gnu_inline attribute is present on all inline declarations, another when -std=c99 , -std=gnu99 or an option for a later C version is used (without -fgnu89-inline ), and the third is used when compiling C++.

What is the C99 specification for inline declarations?

The specification for inline is section 6.7.4 of the C99 standard (ISO/IEC 9899:1999). Unfortunately this isn’t freely available. The following possibilities exist: A function where all the declarations (including the definition) mention inline and never extern. There must be a definition in the same translation unit.