parse specific-arch dependencies correctly on single-arch systems

On single-arch the parsing was creating groupnames like 'apt:amd64' even
through it should be 'apt' and a package in it belonging to architecture
amd64. The result for foreign architectures was as expected: The
dependency isn't satisfiable, but for native architecture it means the
wrong package (ala apt:amd64:amd64) is linked so this is also not
satisfiable, which is very much not expected.

No longer excluding single-arch from this codepath allows the generation
of the correct links, which still link to non-exisiting packages for
foreign dependencies, but natives link to the expected native package
just as if no architecture was given.

For negative arch-specific dependencies ala Conflicts this matter was
worse as apt will believe there isn't a Conflict to resolve, tricking it
into calculating a solution dpkg will refuse.

Architecture specific positive dependencies are rare in jessie – the
only one in amd64 main is foreign –, negative dependencies do not even
exist. Neither class has a native specimen, so no package in jessie is
effected by this bug, but it might be interesting for stretch upgrades.
This also means the regression potential is very low.

Closes: 777760

1 files changed, 1 insertions, 1 deletions

diff --git a/apt-pkg/deb/deblistparser.cc b/apt-pkg/deb/deblistparser.cc
index 4eef66c2b..213235c2b 100644
--- a/apt-pkg/deb/deblistparser.cc
+++ b/apt-pkg/deb/deblistparser.cc
@@ -770,7 +770,7 @@ bool debListParser::ParseDepends(pkgCache::VerIterator &Ver,
 	 if (NewDepends(Ver,Package,"none",Version,Op,Type) == false)
 	    return false;
       }
-      else if (MultiArchEnabled == true && found != string::npos &&
+      else if (found != string::npos &&
 	       strcmp(Package.c_str() + found, ":any") != 0)
       {
 	 string Arch = Package.substr(found+1, string::npos);