The [http://fedoraproject.org/wiki/Packaging:Guidelines#Packaging_Static_Libraries Packaging Guidelines on "Packaging Static Libraries"] mandate

{{{
%package devel
Provides: foo-static = %{version}-%{release}
}}}

while the [http://fedoraproject.org/wiki/PackagingGuidelines#Explicit_Requires
Packaging Guidelines on "Explicit Requires"] mandate using %{?_isa} for arch specific requirements:

{{{
Requires: libfubar%{?_isa} >= 0:1.2.3-7
}}}

Aren't static library dependencies (and thus the "Provides:" tag) also
arch dependent, and thus in need of %{?_isa}?