* apt-pkg/pkgcache.cc:

  - ignore negative dependencies applying in the same group for
    M-A:same packages on the real package name as self-conflicts

apt-pkg/depcache.cc

@@ -346,7 +346,7 @@ bool pkgDepCache::CheckDep(DepIterator Dep,int Type,PkgIterator &Res)
    /* Check simple depends. A depends -should- never self match but 
       we allow it anyhow because dpkg does. Technically it is a packaging
       bug. Conflicts may never self match */
-   if (Dep.TargetPkg() != Dep.ParentPkg() || Dep.IsNegative() == false)
+   if (Dep.IsIgnorable(Res) == false)
    {
       PkgIterator Pkg = Dep.TargetPkg();
       // Check the base package

apt-pkg/pkgcache.cc

@@ -690,8 +690,29 @@ void pkgCache::DepIterator::GlobOr(DepIterator &Start,DepIterator &End)
    on virtual packages. */
 bool pkgCache::DepIterator::IsIgnorable(PkgIterator const &Pkg) const
 {
-   if (ParentPkg() == TargetPkg())
-      return IsNegative();
+   if (IsNegative() == false)
+      return false;
+
+   pkgCache::PkgIterator PP = ParentPkg();
+   pkgCache::PkgIterator PT = TargetPkg();
+   if (PP->Group != PT->Group)
+      return false;
+   // self-conflict
+   if (PP == PT)
+      return true;
+   pkgCache::VerIterator PV = ParentVer();
+   // ignore group-conflict on a M-A:same package - but not our implicit dependencies
+   // so that we can have M-A:same packages conflicting with their own real name
+   if ((PV->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
+   {
+      // Replaces: ${self}:other ( << ${binary:Version})
+      if (S->Type == pkgCache::Dep::Replaces && S->CompareOp == pkgCache::Dep::Less && strcmp(PV.VerStr(), TargetVer()) == 0)
+	 return false;
+      // Breaks: ${self}:other (!= ${binary:Version})
+      if (S->Type == pkgCache::Dep::DpkgBreaks && S->CompareOp == pkgCache::Dep::NotEquals && strcmp(PV.VerStr(), TargetVer()) == 0)
+	 return false;
+      return true;
+   }
 
    return false;
 }

debian/changelog

@@ -5,6 +5,9 @@ apt (0.9.7.6) UNRELEASED; urgency=low
     - ensure that dependencies for packages:none are always generated
     - add 3 missing remap registrations causing a segfault in case
       we use the not remapped iterators after a move of the mmap again
+  * apt-pkg/pkgcache.cc:
+    - ignore negative dependencies applying in the same group for
+      M-A:same packages on the real package name as self-conflicts
 
  -- David Kalnischkies <kalnischkies@gmail.com>  Wed, 19 Sep 2012 11:29:56 +0200
 

test/integration/test-conflicts-real-multiarch-same

@@ -0,0 +1,50 @@
+#!/bin/sh
+set -e
+
+TESTDIR=$(readlink -f $(dirname $0))
+. $TESTDIR/framework
+setupenvironment
+configarchitecture 'amd64' 'i386'
+
+insertpackage 'unstable' 'virtual-provider' 'amd64,i386' '2' 'Provides: virtual
+Conflicts: virtual
+Multi-Arch: same'
+insertpackage 'unstable' 'real' 'amd64,i386' '2' 'Conflicts: real
+Multi-Arch: same'
+insertpackage 'unstable' 'real-provider' 'amd64,i386' '2' 'Provides: real-provider
+Conflicts: real-provider
+Multi-Arch: same'
+setupaptarchive
+
+testequal "Reading package lists...
+Building dependency tree...
+Note, selecting 'virtual-provider' instead of 'virtual'
+Note, selecting 'virtual-provider:i386' instead of 'virtual:i386'
+The following NEW packages will be installed:
+  virtual-provider virtual-provider:i386
+0 upgraded, 2 newly installed, 0 to remove and 0 not upgraded.
+Inst virtual-provider (2 unstable [amd64])
+Inst virtual-provider:i386 (2 unstable [i386])
+Conf virtual-provider (2 unstable [amd64])
+Conf virtual-provider:i386 (2 unstable [i386])" aptget install virtual:* -s -q=0
+
+testequal 'Reading package lists...
+Building dependency tree...
+The following NEW packages will be installed:
+  real real:i386
+0 upgraded, 2 newly installed, 0 to remove and 0 not upgraded.
+Inst real (2 unstable [amd64])
+Inst real:i386 (2 unstable [i386])
+Conf real (2 unstable [amd64])
+Conf real:i386 (2 unstable [i386])' aptget install real:* -s -q=0
+
+# ensure that we are not confused by the provides
+testequal 'Reading package lists...
+Building dependency tree...
+The following NEW packages will be installed:
+  real-provider real-provider:i386
+0 upgraded, 2 newly installed, 0 to remove and 0 not upgraded.
+Inst real-provider (2 unstable [amd64])
+Inst real-provider:i386 (2 unstable [i386])
+Conf real-provider (2 unstable [amd64])
+Conf real-provider:i386 (2 unstable [i386])' aptget install real-provider:* -s -q=0