Right, let's scratch this itch!! I check whether the 'strip' program (which might presumably be applied to the executables at installation time) would yield executables with different checksums... no it does not. Staying with 'cp': a hexdump has the exact same size for two different copies. A 'hexdump -C' and subsequent 'diff' reveals a lot of differences. Question: what sections of the ELF file are the differing ones? A dissassembly using "objdump --disassemble /bin/cp" and subsequent diff shows no difference (as hoped). However, two "objdump --full-contents" and a perl program later (to align the results and check the difference), the truth is revealed: Section ".gnu.liblist" differs almost entirely Section ".gnu.conflict" differs almost entirely Section ".got" differs almost entirely Section ".got.plt" differs almost entirely These are the only sections that differ. Why? These sections are probably set by "prelink". Seems obvious in retrospect. Let's verify with 'prelink' On Machine 1: $ prelink --verify /bin/cp > prelinked_cp $ echo $? 0 $ md5sum prelinked_cp 78aa4c9712040c29ac2f1d464fffbfac prelinked_cp On Machine 2: $ prelink --verify /bin/cp > prelinked_cp $ echo $? 0 $ md5sum prelinked_cp 78aa4c9712040c29ac2f1d464fffbfac prelinked_cp Voilà, that's it. The non-prelinked /bin/cp yields identical Md5 sums. Now, I'm still not sure why 'prelink' would create differing binaries, but I can live with that. -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
