1 files changed, 14 insertions, 15 deletions
diff --git a/src/corelib/tools/qvarlengtharray.h b/src/corelib/tools/qvarlengtharray.h
index 2c88fbef2b..02015be904 100644
--- a/src/corelib/tools/qvarlengtharray.h
+++ b/src/corelib/tools/qvarlengtharray.h
@@ -653,23 +653,22 @@ QVarLengthArray(InputIterator, InputIterator) -> QVarLengthArray<ValueType>;
 
 template <class T, qsizetype Prealloc>
 Q_INLINE_TEMPLATE QVarLengthArray<T, Prealloc>::QVarLengthArray(qsizetype asize)
+    : QVarLengthArray()
 {
-    this->s = asize;
-    static_assert(Prealloc > 0, "QVarLengthArray Prealloc must be greater than 0.");
-    Q_ASSERT_X(size() >= 0, "QVarLengthArray::QVarLengthArray()", "Size must be greater than or equal to 0.");
-    if (size() > Prealloc) {
-        this->ptr = malloc(size() * sizeof(T));
-        Q_CHECK_PTR(data());
-        this->a = size();
-    } else {
-        this->ptr = this->array;
-        this->a = Prealloc;
-    }
-    if constexpr (QTypeInfo<T>::isComplex) {
-        T *i = end();
-        while (i != begin())
-            new (--i) T;
+    Q_ASSERT_X(asize >= 0, "QVarLengthArray::QVarLengthArray(qsizetype)",
+               "Size must be greater than or equal to 0.");
+
+    // historically, this ctor worked for non-copyable/non-movable T, so keep it working, why not?
+    // resize(asize) // this requires a movable or copyable T, can't use, need to do it by hand
+
+    if (asize > Prealloc) {
+        this->ptr = malloc(asize * sizeof(T));
+        Q_CHECK_PTR(this->ptr);
+        this->a = asize;
     }
+    if constexpr (QTypeInfo<T>::isComplex)
+        std::uninitialized_default_construct_n(data(), asize);
+    this->s = asize;
 }
 
 template <class T>