Thread: pragma pack in a preprocessing directive

I want to put #pragma pack(n) as a preprocessor define.
eg

Code:

#define PACK_ON(n)                  _Pragma("pack(n)")
PACK_ON(2)

I get the compile warning:

Code:

warning: unknown action 'n' for '#pragma pack' - ignored

I've also tried this

Code:

DO_PRAGMA(x)                  _Pragma(#x)
#define PACK_ON(n)                  DO_PRAGMA(pack(n))
PACK_ON(2)

but get error:

Code:

_Pragma takes a parenthesized string literal

How do I get around this ?