From 36b3dd8cfe1b932bd60f13606e9bfe23d8d91ffd Mon Sep 17 00:00:00 2001
From: Todd Gamblin <tgamblin@llnl.gov>
Date: Sun, 5 Mar 2017 21:41:18 -0800
Subject: [PATCH] Package.possible_dependencies() descends into virtuals.

---
 lib/spack/spack/package.py | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/lib/spack/spack/package.py b/lib/spack/spack/package.py
index 57298368738..ff8c629ee7d 100644
--- a/lib/spack/spack/package.py
+++ b/lib/spack/spack/package.py
@@ -601,10 +601,19 @@ def possible_dependencies(self, visited=None):
 
         visited.add(self.name)
         for name in self.dependencies:
-            if name not in visited and not spack.spec.Spec(name).virtual:
+            if name in visited:
+                continue
+
+            spec = spack.spec.Spec(name)
+            if not spec.virtual:
                 pkg = spack.repo.get(name)
                 for name in pkg.possible_dependencies(visited):
                     visited.add(name)
+            else:
+                for provider in spack.repo.providers_for(spec):
+                    pkg = spack.repo.get(provider.name)
+                    for name in pkg.possible_dependencies(visited):
+                        visited.add(name)
 
         return visited