diff --git a/src/solver.rs b/src/solver.rs
index ebbe89ef..92c1c0ba 100644
--- a/src/solver.rs
+++ b/src/solver.rs
@@ -393,7 +393,7 @@ impl<P: Package, VS: VersionSet> DependencyProvider for OfflineDependencyProvide
         &self,
         package: &P,
         version: &VS::V,
-    ) -> Result<Dependencies<Self::P, Self::VS, Self::M>, Self::Err> {
+    ) -> Result<Dependencies<P, VS, Self::M>, Infallible> {
         Ok(match self.dependencies(package, version) {
             None => {
                 Dependencies::Unavailable("its dependencies could not be determined".to_string())