diff --git a/src/ir/named.rs b/src/ir/named.rs
index 1af98a26ba..2bab5e4e9e 100644
--- a/src/ir/named.rs
+++ b/src/ir/named.rs
@@ -322,12 +322,14 @@ impl<'ctx, 'gen> MonotoneFramework for UsedTemplateParameters<'ctx, 'gen> {
 
         for item in whitelisted_items.iter().cloned() {
             dependencies.entry(item).or_insert(vec![]);
-            used.insert(item, Some(ItemSet::new()));
+            used.entry(item).or_insert(Some(ItemSet::new()));
 
             {
                 // We reverse our natural IR graph edges to find dependencies
                 // between nodes.
                 item.trace(ctx, &mut |sub_item, _| {
+                    used.entry(sub_item).or_insert(Some(ItemSet::new()));
+
                     // We won't be generating code for items that aren't
                     // whitelisted, so don't bother keeping track of their
                     // template parameters. But isn't whitelisting the
@@ -353,12 +355,17 @@ impl<'ctx, 'gen> MonotoneFramework for UsedTemplateParameters<'ctx, 'gen> {
                     &TypeKind::TemplateInstantiation(ref inst) => {
                         let decl = ctx.resolve_type(inst.template_definition());
                         let args = inst.template_arguments();
+
                         // Although template definitions should always have
                         // template parameters, there is a single exception:
                         // opaque templates. Hence the unwrap_or.
                         let params = decl.self_template_params(ctx)
                             .unwrap_or(vec![]);
+
                         for (arg, param) in args.iter().zip(params.iter()) {
+                            used.entry(*arg).or_insert(Some(ItemSet::new()));
+                            used.entry(*param).or_insert(Some(ItemSet::new()));
+
                             dependencies.entry(*arg)
                                 .or_insert(vec![])
                                 .push(*param);
@@ -368,6 +375,28 @@ impl<'ctx, 'gen> MonotoneFramework for UsedTemplateParameters<'ctx, 'gen> {
                 });
         }
 
+        if cfg!(feature = "testing_only_extra_assertions") {
+            // Invariant: The `used` map has an entry for every whitelisted
+            // item, as well as all explicitly blacklisted items that are
+            // reachable from whitelisted items.
+            //
+            // (This is so that every item we call `constrain` on is guaranteed
+            // to have a set of template parameters, and we can allow
+            // blacklisted templates to use all of their parameters).
+            for item in whitelisted_items.iter() {
+                extra_assert!(used.contains_key(item));
+                item.trace(ctx, &mut |sub_item, _| {
+                    extra_assert!(used.contains_key(&sub_item));
+                }, &())
+            }
+
+            // Invariant: the `dependencies` map has an entry for every
+            // whitelisted item.
+            for item in whitelisted_items.iter() {
+                extra_assert!(dependencies.contains_key(item));
+            }
+        }
+
         UsedTemplateParameters {
             ctx: ctx,
             used: used,
diff --git a/src/lib.rs b/src/lib.rs
index 993cd1c0c0..1e762f72ed 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -235,11 +235,11 @@ impl Builder {
         if !self.options.whitelist_recursively {
             output_vector.push("--no-recursive-whitelist".into());
         }
-  
+
         if self.options.objc_extern_crate {
             output_vector.push("--objc-extern-crate".into());
         }
-    
+
         if self.options.builtins {
             output_vector.push("--builtins".into());
         }
@@ -249,15 +249,6 @@ impl Builder {
             output_vector.push(prefix.clone());
         }
 
-        self.options
-            .clang_args
-            .iter()
-            .map(|item| {
-                     output_vector.push("--clang-args".into());
-                     output_vector.push(item.trim_left_matches("^").trim_right_matches("$").into());
-                 })
-            .count();
-
         if let Some(ref dummy) = self.options.dummy_uses {
             output_vector.push("--dummy-uses".into());
             output_vector.push(dummy.clone());
@@ -316,7 +307,7 @@ impl Builder {
         if self.options.codegen_config.destructors {
             options.push("destructors".into());
         }
-        
+
         output_vector.push(options.join(","));
 
         if !self.options.codegen_config.methods {
@@ -410,6 +401,18 @@ impl Builder {
                  })
             .count();
 
+        if !self.options.clang_args.is_empty() {
+            output_vector.push("--".into());
+            self.options
+                .clang_args
+                .iter()
+                .cloned()
+                .map(|item| {
+                    output_vector.push(item);
+                })
+                .count();
+        }
+
         output_vector
     }
 
@@ -1243,7 +1246,7 @@ fn commandline_flag_unit_test_function() {
 
     assert!(test_cases.iter().all(|ref x| command_line_flags.contains(x)) );
 
-    //Test 2 
+    //Test 2
     let bindings = ::builder().header("input_header")
                               .whitelisted_type("Distinct_Type")
                               .whitelisted_function("safe_function");