architecture wildcards, type-handling, etc.
Since etch, dpkg has supported architecture wildcards such as "linux-any" and
"any-powerpc", which can, among other things, be used to express Linux-only
build dependencies like this:
Build-Depends: libcap2-dev [linux-any]
instead of one of the previous approaches:
Build-Depends: libcap2-dev | not+linux-gnu # works, but not documented(?)
or using type-handling to expand the wildcard manually:
Build-Depends: libcap2-dev [alpha amd64 arm armeb armel hppa i386 ia64 lpia
m32r m68k mips mipsel powerpc ppc64 s390 s390x sh3 sh3eb sh4 sh4eb sparc]
The latter two approaches have obvious flaws, but it seems that no one is using
the built-in dpkg approach. Is there anything wrong with it? Are people just
not aware of it?
Partial answer: pbuilder doesn't support that style yet, so you can't build
packages that way (bug #363193).