Macros can even accept arguments and such macros are known as function-like macros. This is much better, but it won’t save you if you invoke SQUARE with an expression having side effects.SQUARE(++i) evaluates to ((++i)*(++i)) when the effect you probably wanted was more like (++i, (i*i)). Sure, they have a bit of a strange syntax, but they “behave” like normal functions.Then what is the difference?Well, macros are a text processing feature. Whenever calling to inline function is made, function call would be replaced by definition of inline function.Macro SQUARE above is typical of naive macro usage and demonstrates one of the weaknesses of C macros. It is possible for a C program to print the currently executing line of source code, the file of the source code, and the name of the current function. An empty formal parameter list is legal: such a macro can be used to simulate a function that takes no arguments. Der Makro-Funktion werden die zwei Namen der Variablen und der Datentyp im Parameter mitgeteilt. Awesome job. It allows variable arguments list and displays arguments on standard output as per format specified.Here, TRACE_LOG is the macro defined. Lerne besser zu programmieren und nimm am kostenlosen Email-Kurs teil: C99 adds support for function-like macros with a variable number of arguments. Variable arguments are supported with the use of “…” in input argument of macro and ##args in input argument of macro value.Conditional macros are very useful to apply conditions. Macros are used for short operations and it avoids function call overhead. Compiler interprets the inline keyword as a mere hint or request to substitute the code of function into its function call. Macros provide text replacement functionality at pre-processing time.Now let’s see an example through which we will confirm that macros are replaced by their values at pre-processing time. If compiler optimization has been disabled, then inline functions would not serve their purpose and their function call would not be replaced by their function definition.To have GCC inline your function regardless of optimization level, declare the function with the “always_inline” attribute:Inline functions provides following advantages over macros.It is a common misconception that inlining always equals faster code. I’m on a phone that suspiciously doesn’t like c/ping so this is paraphrased, but what you have is kinda like this:The problem is that the curly braces you wrapped around int s[2]; are that variable’s scope. If some part of code needs to be executed for release 1 of project and some other part of code needs to be executed for release 2, then it can be easily achieved through conditional macros.To comment multiples lines of code, macro is used commonly in way given below :Here, we will understand above features of macro through working program that is given below.Here, we can see that “commented code 1”, “commented code 2” are not printed because these lines of code are commented under #if 0 macro. To invoke a macro that takes arguments, you write the name of the macro followed by a list of actual arguments in parentheses, separated by commas. Da es sich hier um Textersetzungen handelt, werden Datentypen nicht beachtet.Dieses Beispiel teilt einen Variablen-Wert mittels einer Makro-Funktion durch zwei.Nach dem Präprozessor sieht der Quelltext wie folgt aus. but whether an inline function serves your purpose in a positive or in a negative way depends purely on your code design and is largely debatable.Compiler does inlining for performing optimizations. Wenn der Name eines Makros im Programm Quelltext oder in den Argumenten bestimmter anderer Präprozessorbefehle erkannt wird, wird er als ein Aufrufvorgang dieses Makros behandelt.

Man kann diesen Makros, wie bei normalen Funktionen auch,  Argumente übergeben. Only, we need to specify “inline” keyword in its definition. Basically they are inlined with its function call.Even there is no guarantee that the function will actually be inlined. Macros are categorized into two main groups: object-like macros and function-like macros. This expression uses the rather obscure C comma operator, about which more could be written.These difficulties with macros are why C has evolved inline functions.Hi, all your posts there are very useful on my work! 1. It can be useful if tokens are concatenated into code to simplify some complex declarations. The … ILE C++ supports function-like macros … Here is a C program :The command above will produce all the intermediate files in the So you see that the macro MAX_SIZE was replaced with it’s value (10) in preprocessing stage of the compilation process.Macros are handled by the pre-compiler, and are thus guaranteed to be inlined. // This is an object-like macro #define PI 3.14159265358979 // This is a function-like macro. C macros __LINE__, __FILE__ and __func__. c) Macro don’t have namespace, so a macro in one section of code can affect other section. So its scope ends before you actually do anything with it. First, character string is logged by TRACE_LOG macro, then multiple arguments of different types are also logged as shown in second call of TRACE_LOG macro. The Concept of C Macros.