g++ linkage on 64 bit

/usr/bin/ld: /home/nix/KdeDev/kdevelop/build/lib/libqxcppunit.a(testrunner.o):
relocation R_X86_64_32S against `vtable for QxCppUnit::TestRunner' can not be
used when making a shared object; recompile with -fPIC
/home/nix/KdeDev/kdevelop/build/lib/libqxcppunit.a: could not read symbols:
Bad value
collect2: ld returned 1 exit status
make[2]: *** [lib/kdevxtest.so] Error 1

A cookie for those that decipher this g++ gibberish. And yes, "-fPIC" was present. Apaku, who's mentoring me, told me this happens when you try to link a static library into a shared one. Apparently this is not supported in the 64bit gcc implementation and hence forbidden in KDE. Funnily enough the same construct runs without a hitch on x86.

Related to this I learned about gcc's DSO visibility concept. Marking symbols as visible in a shared library is typically done with an export macro. In the original QxRunner this macro was activated externally by the buildsystem, which I overlooked when converting to CMake. This resulted in totally mangled shared libs ... not good.