diff --git a/gcc/d/d-convert.cc b/gcc/d/d-convert.cc
index d43485dca77..cd6551e64f3 100644
--- a/gcc/d/d-convert.cc
+++ b/gcc/d/d-convert.cc
@@ -502,6 +502,15 @@ convert_expr (tree exp, Type *etype, Type *totype)
 	  gcc_assert (totype->size () == etype->size ());
 	  result = build_vconvert (build_ctype (totype), exp);
 	}
+      else if (tbtype->ty == Tvector && tbtype->size () == ebtype->size ())
+	{
+	  /* Allow casting from array to vector as if its an unaligned load.  */
+	  tree type = build_ctype (totype);
+	  tree unaligned_type = build_variant_type_copy (type);
+	  SET_TYPE_ALIGN (unaligned_type, 1 * BITS_PER_UNIT);
+	  TYPE_USER_ALIGN (unaligned_type) = 1;
+	  result = convert (type, build_vconvert (unaligned_type, exp));
+	}
       else
 	{
 	  error ("cannot cast expression of type %qs to type %qs",
@@ -636,6 +645,39 @@ convert_for_rvalue (tree expr, Type *etype, Type *totype)
       break;
     }
 
+  if (tbtype->ty == Tsarray
+      && ebtype->ty == Tsarray
+      && tbtype->nextOf ()->ty == ebtype->nextOf ()->ty
+      && INDIRECT_REF_P (expr)
+      && CONVERT_EXPR_CODE_P (TREE_CODE (TREE_OPERAND (expr, 0)))
+      && TREE_CODE (TREE_OPERAND (TREE_OPERAND (expr, 0), 0)) == ADDR_EXPR)
+    {
+      /* If expression is a vector that was casted to an array either by
+	 explicit type cast or by taking the vector's `.array' value, strip the
+	 reinterpret cast and build a constructor instead.  */
+      tree ptr = TREE_OPERAND (TREE_OPERAND (expr, 0), 0);
+
+      if (VECTOR_TYPE_P (TREE_TYPE (TREE_TYPE (ptr))))
+	{
+	  /* Rewrite: `*(Array *)&vector'
+		into: `{ vector[0], vector[1], ... }'  */
+	  tree array = d_save_expr (TREE_OPERAND (ptr, 0));
+	  array = build1 (VIEW_CONVERT_EXPR, TREE_TYPE (expr), array);
+
+	  uinteger_t dim = tbtype->isTypeSArray ()->dim->toUInteger ();
+	  vec <constructor_elt, va_gc> *elms = NULL;
+	  for (uinteger_t i = 0; i < dim; i++)
+	    {
+	      tree index = size_int (i);
+	      tree value = build4 (ARRAY_REF, TREE_TYPE (TREE_TYPE (array)),
+				   array, index, NULL_TREE, NULL_TREE);
+	      CONSTRUCTOR_APPEND_ELT (elms, index, value);
+	    }
+
+	  return build_constructor (build_ctype (totype), elms);
+	}
+    }
+
   return result ? result : convert_expr (expr, etype, totype);
 }
 
@@ -696,7 +738,7 @@ convert_for_assignment (tree expr, Type *etype, Type *totype)
       return expr;
     }
 
-  return convert_expr (expr, etype, totype);
+  return convert_for_rvalue (expr, etype, totype);
 }
 
 /* Return a TREE representation of EXPR converted to represent
diff --git a/gcc/d/dmd/expressionsem.c b/gcc/d/dmd/expressionsem.c
index 5ae5fe6a717..fe90039d6f0 100644
--- a/gcc/d/dmd/expressionsem.c
+++ b/gcc/d/dmd/expressionsem.c
@@ -6330,6 +6330,7 @@ public:
         if (tob->ty == Tvector && t1b->ty != Tvector)
         {
             result = new VectorExp(exp->loc, exp->e1, exp->to);
+            result = expressionSemantic(result, sc);
             return;
         }
 
diff --git a/gcc/d/expr.cc b/gcc/d/expr.cc
index 85269c6b2be..eb5feffef6a 100644
--- a/gcc/d/expr.cc
+++ b/gcc/d/expr.cc
@@ -3034,14 +3034,13 @@ public:
 
   void visit (VectorExp *e)
   {
-    tree type = build_ctype (e->type);
-
     /* First handle array literal expressions.  */
     if (e->e1->op == TOKarrayliteral)
       {
 	ArrayLiteralExp *ale = e->e1->isArrayLiteralExp ();
 	vec <constructor_elt, va_gc> *elms = NULL;
 	bool constant_p = true;
+	tree type = build_ctype (e->type);
 
 	vec_safe_reserve (elms, ale->elements->length);
 	for (size_t i = 0; i < ale->elements->length; i++)
@@ -3061,9 +3060,16 @@ public:
 	else
 	  this->result_ = build_constructor (type, elms);
       }
+    else if (e->e1->type->toBasetype ()->ty == Tsarray)
+      {
+	/* Build a vector representation from a static array.  */
+	this->result_ = convert_expr (build_expr (e->e1, this->constp_),
+				      e->e1->type, e->type);
+      }
     else
       {
 	/* Build constructor from single value.  */
+	tree type = build_ctype (e->type);
 	tree value = d_convert (TREE_TYPE (type),
 				build_expr (e->e1, this->constp_, true));
 	this->result_ = build_vector_from_val (type, value);
diff --git a/gcc/d/toir.cc b/gcc/d/toir.cc
index eaee6f7e803..460edc15143 100644
--- a/gcc/d/toir.cc
+++ b/gcc/d/toir.cc
@@ -1090,6 +1090,7 @@ public:
 	    /* Generate: (<retval> = expr, return <retval>);  */
 	    tree expr = build_expr_dtor (s->exp);
 	    tree init = stabilize_expr (&expr);
+	    expr = convert_for_rvalue (expr, s->exp->type, type);
 	    expr = build_assign (INIT_EXPR, this->func_->shidden, expr);
 	    add_stmt (compound_expr (init, expr));
 	  }
diff --git a/gcc/testsuite/gdc.dg/pr106139a.d b/gcc/testsuite/gdc.dg/pr106139a.d
new file mode 100644
index 00000000000..f635eabc745
--- /dev/null
+++ b/gcc/testsuite/gdc.dg/pr106139a.d
@@ -0,0 +1,36 @@
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106139
+// { dg-do compile }
+
+alias A = int[4];
+
+static if (__traits(compiles, __vector(A))):
+
+A vector2array(__vector(A) v)
+{
+    return cast(A)v;
+}
+
+void vector2array(ref A a, __vector(A) v)
+{
+    a = cast(A)v;
+}
+
+__vector(A) array2vector(A a)
+{
+    return cast(__vector(A)) a;
+}
+
+void array2vector(ref __vector(A) v, A a)
+{
+    v = cast(__vector(A))a;
+}
+
+A vector2array_array(__vector(A) v)
+{
+    return v.array;
+}
+
+void vector2array_array(ref A a, __vector(A) v)
+{
+    a = v.array;
+}
diff --git a/gcc/testsuite/gdc.dg/pr106139b.d b/gcc/testsuite/gdc.dg/pr106139b.d
new file mode 100644
index 00000000000..f9caf026f86
--- /dev/null
+++ b/gcc/testsuite/gdc.dg/pr106139b.d
@@ -0,0 +1,36 @@
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106139
+// { dg-do compile }
+
+alias A = float[4];
+
+static if (__traits(compiles, __vector(A))):
+
+A vector2array(__vector(A) v)
+{
+    return cast(A)v;
+}
+
+void vector2array(ref A a, __vector(A) v)
+{
+    a = cast(A)v;
+}
+
+__vector(A) array2vector(A a)
+{
+    return cast(__vector(A)) a;
+}
+
+void array2vector(ref __vector(A) v, A a)
+{
+    v = cast(__vector(A))a;
+}
+
+A vector2array_array(__vector(A) v)
+{
+    return v.array;
+}
+
+void vector2array_array(ref A a, __vector(A) v)
+{
+    a = v.array;
+}
diff --git a/gcc/testsuite/gdc.dg/pr106139c.d b/gcc/testsuite/gdc.dg/pr106139c.d
new file mode 100644
index 00000000000..3b6b7a83341
--- /dev/null
+++ b/gcc/testsuite/gdc.dg/pr106139c.d
@@ -0,0 +1,27 @@
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106139
+// { dg-do compile }
+
+alias V = int[4];
+alias A = float[4];
+
+static if (__traits(compiles, __vector(V))):
+
+A vector2array(__vector(V) v)
+{
+    return cast(A)v;
+}
+
+void vector2array(ref A a, __vector(V) v)
+{
+    a = cast(A)v;
+}
+
+__vector(V) array2vector(A a)
+{
+    return cast(__vector(V)) a;
+}
+
+void array2vector(ref __vector(V) v, A a)
+{
+    v = cast(__vector(V))a;
+}
diff --git a/gcc/testsuite/gdc.dg/pr106139d.d b/gcc/testsuite/gdc.dg/pr106139d.d
new file mode 100644
index 00000000000..4c6f0ef3a3a
--- /dev/null
+++ b/gcc/testsuite/gdc.dg/pr106139d.d
@@ -0,0 +1,27 @@
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106139
+// { dg-do compile }
+
+alias V = float[4];
+alias A = int[4];
+
+static if (__traits(compiles, __vector(V))):
+
+A vector2array(__vector(V) v)
+{
+    return cast(A)v;
+}
+
+void vector2array(ref A a, __vector(V) v)
+{
+    a = cast(A)v;
+}
+
+__vector(V) array2vector(A a)
+{
+    return cast(__vector(V)) a;
+}
+
+void array2vector(ref __vector(V) v, A a)
+{
+    v = cast(__vector(V))a;
+}
diff --git a/gcc/testsuite/gdc.test/fail_compilation/ice20264.d b/gcc/testsuite/gdc.test/fail_compilation/ice20264.d
new file mode 100644
index 00000000000..0d697e22c9f
--- /dev/null
+++ b/gcc/testsuite/gdc.test/fail_compilation/ice20264.d
@@ -0,0 +1,13 @@
+/*
+DISABLED: freebsd32 linux32 osx32 win32
+TEST_OUTPUT:
+---
+fail_compilation/ice20264.d(12): Error: `cast(__vector(float[4]))a` is not an lvalue and cannot be modified
+---
+*/
+
+void foo(float *a)
+{
+    alias float4 = __vector(float[4]);
+    cast(float4)(a) = 1.0f;
+}
