prefer upgrading installed provides satisfier

If you have chosen to install a foreign architecture provider it is
more reasonable to keep this provider instead of removing this one to
replace it with a newer version from a (usually) more preferred arch.

Git-Dch: Ignore

diff --git a/apt-pkg/depcache.cc b/apt-pkg/depcache.cc
index c6fb63be1002ab8a54157205bd33d56c355a1d7e..8281949f97c5e776030a018d7bd44f2ae6958d5f 100644 (file)
--- a/apt-pkg/depcache.cc
+++ b/apt-pkg/depcache.cc
@@ -1016,6 +1016,8 @@ struct CompareProviders {
         if (instA != instB)
            return instA == false;
       }
+      if ((A->CurrentVer == 0 || B->CurrentVer == 0) && A->CurrentVer != B->CurrentVer)
+        return A->CurrentVer == 0;
       // Prefer packages in the same group as the target; e.g. foo:i386, foo:amd64
       if (A->Group != B->Group)
       {