diff --git a/internal/lsp/source/diagnostics.go b/internal/lsp/source/diagnostics.go
index 4b3b94c..032c4af 100644
--- a/internal/lsp/source/diagnostics.go
+++ b/internal/lsp/source/diagnostics.go
@@ -74,6 +74,9 @@
 	// Updates to the diagnostics for this package may need to be propagated.
 	for _, f := range f.GetActiveReverseDeps(ctx) {
 		pkg := f.GetPackage(ctx)
+		if pkg == nil {
+			continue
+		}
 		for _, filename := range pkg.GetFilenames() {
 			reports[span.FileURI(filename)] = []Diagnostic{}
 		}