C language preprocessor behavior

Posted by khanna_param on Stack Overflow See other posts from Stack Overflow or by khanna_param
Published on 2010-05-29T03:56:20Z Indexed on 2010/05/29 6:02 UTC
Read the original article Hit count: 309

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preprocessor

There are different kind of macros in C language, nested macro is one of them.

Considering a program with the following macro

#define HYPE(x,y) (SQUR(x)+SQUR(y))
#define SQUR(x)   (x*x)

Using this we can successfully compile to get the result.

As we all know the C preprocessor replaces all the occurrence of the identifiers with the replacement-string. Considering the above example I would like to know how many times the C preprocessor traverses the program to replace the macro with the replacement values. I assume it cannot be done in one go.

C language preprocessor behavior

Posted by khanna_param on Super User See other posts from Super User or by khanna_param
Published on 2010-05-29T03:56:20Z Indexed on 2010/05/29 4:12 UTC
Read the original article Hit count: 309

Filed under:

macros

|

c

|

preprocessor

There are different kind of macros in C language, nested macro is one of them.

Considering a program with the following macro

#define HYPE(x,y) (SQUR(x)+SQUR(y))
#define SQUR(x)   (x*x)

Using this we can successfully compile to get the result.

As we all know the C preprocessor replaces all the occurrence of the identifiers with the replacement-string. Considering the above example I would like to know how many times the C preprocessor traverses the program to replace the macro with the replacement values. I assume it cannot be done in one go.

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