Created attachment 222435 [details]
Add -fcommon to CFLAGS
CLANG has changed its default behaviour by setting -fno-common as the default option, to meet GCC10 behaviour:
"[...] With this change, C code that uses tentative definitions as definitions of a variable in multiple translation units will trigger multiple-definition linker errors. Generally, this occurs when the use of the extern keyword is neglected in the declaration of a variable in a header file. In some cases, no specific translation unit provides a definition of the variable. The previous behavior can be restored by specifying -fcommon. [...]
As a "quick and dirty" workaround I added -fcommon to CFALGS to restore the previous behaviour. A more sophisticated solution (which implies a deeper insight into the codebase of refdb) would be desireable.
Additionaly, I allowed to change the E-Mail address.
Maintainer informed via mail
Created attachment 223661 [details]
mitigate linker error
The applied patchfile (residing in refdb/files) mutually solves the problem occuring on FreeBSD-13 and -14 as well as CURRENT due to changes to linker behaviour of used LLVM11 compiler suite as described above.
Created attachment 223663 [details]
Solving the -fno-common issue on LLVM10+
Given the attached patch, the -fno-common problematic with the reported issue on newer LLVM10+ compiler suites seems to be solved. Not tested thoroughly on FreeBSD < 13.