$ ORIGIN=/usr/local/foo/bar perl Makefile.PL 
Writing Makefile for XML::Parser::Expat
Writing Makefile for XML::Parser

$ make
...
rm -f ../blib/arch/auto/XML/Parser/Expat/Expat.so
LD_RUN_PATH="/lib" gcc   -shared -O2 -L/usr/local/lib -fstack-protector Expat.o -Wl,-rpath,/usr/local/foo/bar/../lib -o ../blib/arch/auto/XML/Parser/Expat/Expat.so     \
           -lexpat      \
...

$ readelf -d ./blib/arch/auto/XML/Parser/Expat/Expat.so | grep Lib
 0x000000000000000f (RPATH)              Library rpath: [/usr/local/foo/bar/../lib]
 0x000000000000001d (RUNPATH)            Library runpath: [/usr/local/foo/bar/../lib]