I am trying to link library xy.a composed of x.o containing function x() and y.o containing function y() with d.o giving executable d

I call both x() and y() from d.cpp. When I comment out the function call to y() in d.cpp it links just fine with library xy.a giving executable d BUT when I uncomment the function call to y() I get duplicate variable declaration errors.

Note that I need x.o and y.o in a library because I also link them with e.o to give executable e . Both x() and y() are called from both d and e executables.

I use the same custom include files in x.o y.o d.o and e.o. I am getting duplicate variable errors from the variables declared in these custom include files.

I also include standard include files such as <stdio.h> and <math.h> etc. etc. in all 4 .o's but I don't get duplicate variable errors from these.

I am #ifndef ing the entire include file just as is done with <stdio.h> etc. What am I doing wrong, that at link time I get duplicate variable errors?

Thanks for your help!

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Best Regards,
Lynn P. Tilby
Ph: 480 632-8635
unixprgrmr01@gmail.com