c - How to concatenate strings in the arguments of _Pragma -


the argument of _pragma string think when paste strings in normal c-preprocessor way (ie putting them right next eachother) form new string argument of _pragma. however

_pragma("gcc poison " "puts")

fails error

error: _pragma takes parenthesized string literal

how can circumvented?

this particular example isn't useful , has trivial solution of making them 1 string begin with, end goal stringize macro it

the do_pragma macro in gnu docs defined this

#define do_pragma(x) _pragma (#x)

using this, if put 2 seperate token unstringized next eachother, become stringized. expand macros within definition, must go through 1 level of indirection, define as

#define do_pragma_(x) _pragma (#x) #define do_pragma(x) do_pragma_(x)

using can create shorthands various pragmas this

#define poison(name) do_pragma(gcc poison name) poision(puts)//becomse _pragma("gcc poison puts")

thanks eugene sh. pointing me do_pragma macro


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