Bug#962474: CMAKE_SKIP_RPATH=ON improves reproducibility of CMake builds

[Timo Röhling]

Control: user reproducible-builds at lists.alioth.debian.org
Control: usertag -1 + buildpath toolchain


>> By default, CMake adds an RPATH entry to ELF binaries and deletes it
>> again at install time. However, due to the limitations of some
>> platforms, CMake will actually zero out the RPATH entry in the binary,
>> leaking the original path length and thus making the build not
>> reproducible (see the attached diffoscope output for an example).
>>
>> CMAKE_SKIP_RPATH disables the RPATH machinery and fixes the issue, and
>> since most package won't ever ship with an RPATH entry anyway, I propose
>> adding -DCMAKE_SKIP_RPATH=ON to the default build options.
> Thanks for the suggestion.
>
> Has this proposal been tested on an archive-wide rebuild test to see how
> much breaks with this option set?
I don't know, but I don't think so. I'm not directly involved with the
Reproducible Builds Team, I just pinged them on IRC after I filed this
bug. Cc'ing them now.