Is there any information about when this [%{?_isa}] should be used?
I don't
think I've ever written a spec file that uses it.
*EACH* dependency (*EVERY SINGLE ONE*) should use %{_isa}
unless you are in .noarch land, or unless you will be happy
with any compatible architecture [and this is unlikely
given the frequent cases of un-synchronized mirrors, maintainers
who update branches and rawhide separately, mistakes in
ABI changes, etc.]
This is a ridiculous default. The 3 most common hardware families
all have "compat" architectures which are incompatible in such usage:
i686 and x86_64
ppc and ppc64
armhfp and armv5tel
yum (and/or rpm) should *help* the packager take care of the
99% usual case, instead of laying a trap. The multilib feature
simply didn't think hard enough about the horrendous Usability
problems that multilib creates for packagers and sysadmins
(anyone who updates using the mirror system.)
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