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Not sure why I didn't think to test that out first, but thanks =) Works fine
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Not sure why I didn't think to test that out first, but thanks =) Works fine

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I have some code that I share between visual c++ 2005 and gcc. Within the code, there are a few variadic macros. The problem I have is in the different way gcc and vs handle variadic macro argument lists. VS correctly formats the argument list automatically (inserting leading commas when necessary) by simply using __VA_ARGS__. In gcc, however, ##__VA_ARGS__ is required if a leading comma is needed.<br />
<br />
To deal with this, I was just going to write something like this<br />
<br />
#ifdef WIN32<br />
#define VA_ARGS __VA_ARGS__<br />
#else<br />
#define VA_ARGS ##__VA_ARGS__<br />
#endif /* WIN32*/<br />
<br />
When I compile the code in VS, it seems to work fine. However, gcc &nbsp;gives these errors<br />
<br />
/mnt/backupdrive1/Programm<wbr />ing/pmc_li<wbr />bs/pmc.c:2<wbr />9:17: '##' cannot appear at either end of a macro expansion<br />
/mnt/backupdrive1/Programm<wbr />ing/pmc_li<wbr />bs/pmc.c:2<wbr />9:19: warning: __VA_ARGS__ can only appear in the expansion of a C99 variadic macro<br />
<br />
How can I get the desired result? I appreciate any help
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I have some code that I share between visual c++ 2005 and gcc. Within the code, there are a few variadic macros. The problem I have is in the different way gcc and vs handle variadic macro argument lists. VS correctly formats the argument list automatically (inserting leading commas when necessary) by simply using __VA_ARGS__. In gcc, however, ##__VA_ARGS__ is required if a leading comma is needed.

To deal with this, I was just going to write something like this

#ifdef WIN32
#define VA_ARGS __VA_ARGS__
#else
#define VA_ARGS ##__VA_ARGS__
#endif /* WIN32*/

When I compile the code in VS, it seems to work fine. However, gcc  gives these errors

/mnt/backupdrive1/Programming/pmc_libs/pmc.c:29:17: '##' cannot appear at either end of a macro expansion
/mnt/backupdrive1/Programming/pmc_libs/pmc.c:29:19: warning: __VA_ARGS__ can only appear in the expansion of a C99 variadic macro

How can I get the desired result? I appreciate any help

How to make macros that expand to other special macros (##__VA_ARGS__)

C is a general-purpose, imperative computer programming language, supporting structured programming, lexical variable scope and recursion, while a static type system prevents many unintended operations. By design, C provides constructs that map efficiently to typical machine instructions, so it has found lasting use in applications that had formerly been coded in assembly language, including operating systems as well as various application software for computers ranging from supercomputers to embedded systems. It is distinct from C++ (which has its roots in C) and C#, and many later languages have borrowed directly or indirectly from C.