dll linkage madness

[bryce]

Hello i have been asked to look at a dll "issue" and i cant see why its acting up. However, when the dll builds the linker throws a headcase and spews out a bunch of errors ClientState.obj : error LNK2005: "char const * * RPD_APP_FILE_EXT" (?RPD_APP_FILE_EXT@@3PAPBDA) already defined in ClientControl.obj DisplayControl.obj : error LNK2005: "char const * * RPD_APP_FILE_EXT" (?RPD_APP_FILE_EXT@@3PAPBDA) already defined in ClientControl.obj EquipmentID.obj : error LNK2005: "char const * * RPD_APP_FILE_EXT" (?RPD_APP_FILE_EXT@@3PAPBDA) already defined in ClientControl.obj FaultData.obj : error LNK2005: "char const * * RPD_APP_FILE_EXT" (?RPD_APP_FILE_EXT@@3PAPBDA) already defined in ClientControl.obj MSCIntraInterface.obj : error LNK2005: "char const * * RPD_APP_FILE_EXT" (?RPD_APP_FILE_EXT@@3PAPBDA) already defined in ClientControl.obj MsgQueue.obj : error LNK2005: "char const * * RPD_APP_FILE_EXT" (?RPD_APP_FILE_EXT@@3PAPBDA) already defined in ClientControl.obj TcpListener.obj : error LNK2005: "char const * * RPD_APP_FILE_EXT" (?RPD_APP_FILE_EXT@@3PAPBDA) already defined in ClientControl.obj Sort of thing The RPD_APP_EXT is defined in "globaldefines.h" which uses #ifndef GlobalDefines_h #define GlobalDefines_h const char * RPD_APP_FILE_EXT[] = {".RPD", ".RVR", ".UDO", ".RDO", ".ZRP"}; etc etc #endif And as well as that the header files for every class all correctly use #ifndef < sometag > #define < some tag > . (.class definitions etc) #endif also,The compiler settings are set with the multithreaded /md option I was wondering if anyone had any suggestions as to what one might do to fix this issue? regards Bryce --- Publitor, making Pubmed easy. http://www.sohocode.com/publitor

[twing]

Maybe char* const RPD_APP_FILE_EXT[] = {".RPD", ".RVR", ".UDO", ".RDO", ".ZRP"}; Hello World!

[bryce]

yep did that didnt help (much) ;) Bryce --- Publitor, making Pubmed easy. http://www.sohocode.com/publitor

[rpins]

Try this...in globaldefines.h, say #ifndef GlobalDefines_h #define GlobalDefines_h ...other code... extern const char* RPD_APP_FILE_EXT[]; ...other code... #endif And then in some other .cpp file (perhaps globaldefines.cpp), do the actual definition of RPD_APP_FILE_EXT, i.e. in the cpp file: #include "globaldefines.h" const char* RPD_APP_FILE_EXT[] = {".RPD", ".RVR", ".UDO", ".RDO", ".ZRP"}; ...other code... Even if you have include-guards on your headers, if they're included in multiple places and have variable definitions (not just declarations), then you'll usually get those link errors. HTH

[PJ Arends]

maybe because you can not initialize variables in header files?

---

[

](http://www.canucks.com)Sonork 100.11743 Chicken Little "You're obviously a superstar." - Christian Graus about me - 12 Feb '03 Within you lies the power for good - Use it!

[bryce]

all fixed now, turns out one of the developers had been messing with the project settings cheers all bryce --- Publitor, making Pubmed easy. http://www.sohocode.com/publitor