diff --git a/include/nlohmann/detail/view/builder.hpp b/include/nlohmann/detail/view/builder.hpp
index 1722dcc34..ce0336549 100644
--- a/include/nlohmann/detail/view/builder.hpp
+++ b/include/nlohmann/detail/view/builder.hpp
@@ -836,7 +836,10 @@ indent_done:
 
         NLOHMANN_VIEW_ALWAYS_INLINE void open(value_t k)
         {
-            const auto idx = static_cast<std::uint32_t>(emit(k, 0, 0, static_cast<std::size_t>(p - b), 0) - base);
+            // (base is read after emit(), which moves the node array when it
+            // grows; in one expression the order of the two is unspecified)
+            const node* const n = emit(k, 0, 0, static_cast<std::size_t>(p - b), 0);
+            const auto idx = static_cast<std::uint32_t>(n - base);
             if (depth != 0)
             {
                 if (NLOHMANN_VIEW_LIKELY(depth <= 64))
diff --git a/single_include/nlohmann/json_view.hpp b/single_include/nlohmann/json_view.hpp
index cdae60903..9338f691c 100644
--- a/single_include/nlohmann/json_view.hpp
+++ b/single_include/nlohmann/json_view.hpp
@@ -1981,7 +1981,10 @@ indent_done:
 
         NLOHMANN_VIEW_ALWAYS_INLINE void open(value_t k)
         {
-            const auto idx = static_cast<std::uint32_t>(emit(k, 0, 0, static_cast<std::size_t>(p - b), 0) - base);
+            // (base is read after emit(), which moves the node array when it
+            // grows; in one expression the order of the two is unspecified)
+            const node* const n = emit(k, 0, 0, static_cast<std::size_t>(p - b), 0);
+            const auto idx = static_cast<std::uint32_t>(n - base);
             if (depth != 0)
             {
                 if (NLOHMANN_VIEW_LIKELY(depth <= 64))