2 files changed, 11 insertions, 0 deletions
diff --git a/src/librustc_data_structures/accumulate_vec.rs b/src/librustc_data_structures/accumulate_vec.rs
index f50b8cadf15..2e8cca3f4f9 100644
--- a/src/librustc_data_structures/accumulate_vec.rs
+++ b/src/librustc_data_structures/accumulate_vec.rs
@@ -46,6 +46,13 @@ impl<A: Array> AccumulateVec<A> {
         AccumulateVec::Array(ArrayVec::new())
     }
 
+    pub fn is_array(&self) -> bool {
+        match self {
+            AccumulateVec::Array(..) => true,
+            AccumulateVec::Heap(..) => false,
+        }
+    }
+
     pub fn one(el: A::Element) -> Self {
         iter::once(el).collect()
     }
diff --git a/src/librustc_data_structures/small_vec.rs b/src/librustc_data_structures/small_vec.rs
index 74738e61b44..83eb54fade1 100644
--- a/src/librustc_data_structures/small_vec.rs
+++ b/src/librustc_data_structures/small_vec.rs
@@ -50,6 +50,10 @@ impl<A: Array> SmallVec<A> {
         SmallVec(AccumulateVec::new())
     }
 
+    pub fn is_array(&self) -> bool {
+        self.0.is_array()
+    }
+
     pub fn with_capacity(cap: usize) -> Self {
         let mut vec = SmallVec::new();
         vec.reserve(cap);