Don't copy libraries that are already in prime.

integration_tests/snaps/rpath-test/snapcraft.yaml

@@ -0,0 +1,10 @@
+name: rpath-test
+version: 1
+summary: summary
+description: description
+confinement: strict
+
+parts:
+  rpath-test:
+    plugin: make
+    source: src/

integration_tests/snaps/rpath-test/src/Makefile

@@ -0,0 +1,19 @@
+all: main
+
+libfoo.so: foo.h foo.cpp
+	@g++ -fPIC -c foo.cpp
+	@g++ -shared foo.o -o libfoo.so
+	@mkdir -p lib
+	@mv libfoo.so lib/
+
+main: libfoo.so
+	@g++ main.cpp -o binary -Wl,-rpath=\$$ORIGIN/lib -Llib -lfoo
+
+install: main
+	@mkdir -p $(DESTDIR)/lib
+	@cp binary $(DESTDIR)/
+	@cp lib/* $(DESTDIR)/lib/
+
+clean:
+	@rm *.o binary
+	@rm -rf lib

integration_tests/snaps/rpath-test/src/foo.cpp

@@ -0,0 +1,6 @@
+#include "foo.h"
+
+std::string foo()
+{
+	return "hello world";
+}

integration_tests/snaps/rpath-test/src/foo.h

@@ -0,0 +1,3 @@
+#include <string>
+
+std::string foo();

integration_tests/snaps/rpath-test/src/main.cpp

@@ -0,0 +1,8 @@
+#include <iostream>
+#include "foo.h"
+
+int main()
+{
+	std::cout << foo() << std::endl;
+	return 0;
+}

integration_tests/test_rpath.py

@@ -0,0 +1,43 @@
+# -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
+#
+# Copyright (C) 2016 Canonical Ltd
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import os
+
+import integration_tests
+
+from testtools.matchers import (
+    DirExists,
+    FileExists,
+    Not,
+)
+
+
+class RpathTestCase(integration_tests.TestCase):
+
+    def test_origin_rpath(self):
+        project_dir = 'rpath-test'
+        self.run_snapcraft('prime', project_dir)
+
+        primedir = os.path.join(project_dir, 'prime')
+        self.assertThat(os.path.join(primedir, 'binary'), FileExists())
+        self.assertThat(
+            os.path.join(primedir, 'lib', 'libfoo.so'), FileExists())
+
+        # Assert that the $ORIGIN rpath did not result in the library being pulled
+        # in twice.
+        self.assertThat(
+            os.path.join(primedir, os.path.abspath(primedir).lstrip('/')),
+            Not(DirExists()))

snapcraft/internal/pluginhandler.py

@@ -391,6 +391,7 @@ def prime(self, force=False):
         # potentially override the `stage` or `snap` filtering.
         part_dependencies = set()
         staged_dependencies = set()
+        primed_dependencies = set()
         system_dependencies = set()
         for file_path in dependencies:
             if file_path.startswith(self.installdir):
@@ -399,6 +400,9 @@ def prime(self, force=False):
             elif file_path.startswith(self.stagedir):
                 staged_dependencies.add(
                     os.path.relpath(file_path, self.stagedir))
+            elif file_path.startswith(self.snapdir):
+                primed_dependencies.add(
+                    os.path.relpath(file_path, self.snapdir))
             else:
                 system_dependencies.add(file_path.lstrip('/'))