Hi :)

Op gets C:\perl\c\x86_64-w64-mingw32\lib\libkernel32.a(dusfs01262.o): bad reloc address 0x7373622e in section `.text'

So, while "reloc" is mentioned http://search.cpan.org/grep?cpanid=PYTHIAN&release=DBD-Oracle-1.74&string=reloc&i=1&n=1&C=9

1644:       If sqlplus failed due to a linker/symbol/relocation/librar
+y error or similar problem
1645-       then it's likely that you've not configured your environme
+nt correctly.
1646-       $ldlib_note
1647-       set to include the directory containing the Oracle librari
+es.
[download]

What the OP has seems to be more related to version of mingw/gcc toolchain... than oracle paths issue

And http://strawberryperl.com/release-notes/5.20.0.1-64bit.html says New gcc 4.8.2 toolchain + new mingw-w64 v3 runtime and Newly added DBD::Oracle - you have to install 64bit Oracle Instant Client 11.x and make sure you have OCI.DLL in your PATH

So, first thing I'd try is to install a new portable 5.20.0.1-64bit, it can coexist with OPs existing strawberry perl (if installed in a different path), and the OP can migrate his apps one by one to the new install (as soon as he install all the modules he needs, and tests his apps)

Its nice when someone else does the hard work :)