submit/tizen/20160831.052250

Store build_date in .tizen.build-id section to avoid unnecessary rebuilds

    - PROBLEM
    We use OBS to build packages in Tizen.
    There is a mechanism not to rebuild if the result binary is the same.
    For example, there is a dependency graph: A->B->C.
    If A is modified, B would be built.
    If the result RPM of B is not changed, OBS does not trigger a build of C.
    To effectively use this mechanism, each packages make sure that
    the result binary should be the same if the input source is the same.

    This package uses __DATE__ and __TIME__ which make the result binary
    is different everytime it is built.
    To efficiently utilize OBS build mechanism and to modify the package
    as little as possible, I propose to store this macro in .tizen.build-id
    section. OBS build-compare tool does not check *.build-id section
    in the binary.