diff --git a/source/containers.tex b/source/containers.tex
index 5e4ba77219..727e239cd0 100644
--- a/source/containers.tex
+++ b/source/containers.tex
@@ -18635,7 +18635,7 @@
       constexpr flat_multimap(sorted_equivalent_t, initializer_list<value_type> il,
                               const key_compare& comp, const Alloc& a);
 
-    flat_multimap& operator=(initializer_list<value_type>);
+    constexpr flat_multimap& operator=(initializer_list<value_type>);
 
     // iterators
     constexpr iterator               begin() noexcept;