Greetings all!
I seem have run into a rather sticky issue here, and I'm not finding the answers I'm looking for. I'm hoping someone here has the answer to my woes.
I'm building an embedded linux shared library. I've done this many times before. Difference this time is that we are trying to standardize on some debug macro's in the code. In a header file, I have:
#define LIB_ERR(fmtStr,args...) { printf("ERROR: "); (void) printf(fmtStr , ##args );}
I compile this just fine as a shared library, no errors. When I then go to link my application to this, I get:
/home/Proj/Install/usr/local/lib/brd/libBoard.so: undefined reference to `LIB_ERR'
I include <stdio.h> and <stdarg.h> in the header file to find the printf and varadic info.
Compiler is PPC7xx, version 3.3.1 from Montavista, so it "should" be able to support this setup.
We have a different project, using ARM (4.2.x) in a similar setup and there's no issues.
I've read the GNU specs on varadic macro's, tried different spacing in the definition. Removed the first printf (there is a different macro with the 2 printf's that I don't seem to have a problem with, it's only invoked once though.
Using Eclipse, when I roll-over the Macro, it will expand correctly.
Any insight would be greatly appreciated!
Thanks in Advance for your comments!
Steve

That the linker is reporting an undefined symbol for what you have defined as a macro, indicates that in at least one of your files you are not including the needed header file or 'ifdefs' are causing the definition of the macro to be skipped.

That sounds like LIB_ERR is getting interpreted as a function call instead of a macro. Maybe you forgot to #include the definition in one of libBoard's sources? If you compile with -Wall and -Wextra you should get a warning about it, something like "implicit declaration of function LIB_ERR".

EDIT: whoops, ninja'd by z1p

1 members found this post helpful.

z1p, you nailed it! One (of ~ 12) files was missing the necessary include. I could have sworn it was there. . . (too many files, so little time. . . )
ntubski, the warning's were not enabled for the library build, that's why it was not picked up. I will tweak the build system (not mine, someone else's) to get these turned on!
MANY THANKS! I now have the test application linked and ready for testing.
Regards,
Steve