c++ - Calling a macro only once in the project -


i trying set easylogging++ in project, , run following issue:

macro initialize_easyloggingpp should called once in project. now, if call macro main.cpp , include easylogging++.h in main.cpp - works fine. however, when try include easylogging++.h in more .cpp files, linker issues undefined references (as if macro hasn't been called). if place call macro in file alphabetically before main.cpp, linker resolves normally. in linking phase objects sorted alphabetically.

is there nice way solve issue? or have try force different order of files @ linking time?

i not experienced sort of issues, tried googling it, couldn't find solution. if there similar question, sorry, couldn't find it.

thanks help!

maybe wrap call in function invoke using std::call_once(), example:

void setup_logging() {   static std::once_flag once;   std::call_once(once, [] () { initialize_easyloggingpp(); }); }

that way can call setup_logging() multiple times, macro invoked once.


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