diff --git a/gcc/config/aarch64/aarch64-builtins.cc b/gcc/config/aarch64/aarch64-builtins.cc
index 9b23b6b8c33f1..dacfe74917606 100644
--- a/gcc/config/aarch64/aarch64-builtins.cc
+++ b/gcc/config/aarch64/aarch64-builtins.cc
@@ -1110,6 +1110,8 @@ aarch64_init_simd_builtin_types (void)
 
       if (aarch64_simd_types[i].itype == NULL)
 	{
+          // FIXME: problem happens when we execute this a second time.
+          // Currently fixed by not initializing builtins more than once in dummy-frontend.cc.
 	  tree type = build_vector_type (eltype, GET_MODE_NUNITS (mode));
 	  type = build_distinct_type_copy (type);
 	  SET_TYPE_STRUCTURAL_EQUALITY (type);
diff --git a/gcc/jit/dummy-frontend.cc b/gcc/jit/dummy-frontend.cc
index e9e20a08ae878..c5e54fe9dabd8 100644
--- a/gcc/jit/dummy-frontend.cc
+++ b/gcc/jit/dummy-frontend.cc
@@ -1035,6 +1035,8 @@ jit_end_diagnostic (diagnostic_context *context,
   gcc::jit::active_playback_ctxt->add_diagnostic (context, *diagnostic);
 }
 
+static bool builtins_initialized = false;
+
 /* Language hooks.  */
 
 static bool
@@ -1073,7 +1075,12 @@ jit_langhook_init (void)
      eventually be controllable by a command line option.  */
   mpfr_set_default_prec (256);
 
-  targetm.init_builtins ();
+  // TODO: check if this is a good fix.
+  if (!builtins_initialized)
+  {
+    targetm.init_builtins ();
+    builtins_initialized = true;
+  }
 
   return true;
 }
@@ -1291,6 +1298,39 @@ recording::type* tree_type_to_jit_type (tree type)
     recording::type* element_type = tree_type_to_jit_type (inner_type);
     return element_type->get_pointer();
   }
+  else if (type == unsigned_intTI_type_node)
+  {
+    // TODO: check if this is the correct type.
+    return new recording::memento_of_get_type (&target_builtins_ctxt, GCC_JIT_TYPE_UINT128_T);
+  }
+  else if (INTEGRAL_TYPE_P (type))
+  {
+    // TODO: check if this is the correct type.
+    unsigned int size = tree_to_uhwi (TYPE_SIZE_UNIT (type));
+    return target_builtins_ctxt.get_int_type (size, TYPE_UNSIGNED (type));
+  }
+  else if (SCALAR_FLOAT_TYPE_P (type))
+  {
+    // TODO: check if this is the correct type.
+    unsigned int size = tree_to_uhwi (TYPE_SIZE_UNIT (type));
+    enum gcc_jit_types type;
+    switch (size) {
+        case 2:
+            type = GCC_JIT_TYPE_FLOAT16;
+            break;
+        case 4:
+            type = GCC_JIT_TYPE_FLOAT32;
+            break;
+        case 8:
+            type = GCC_JIT_TYPE_FLOAT64;
+            break;
+        default:
+            fprintf (stderr, "Unexpected float size: %d\n", size);
+            abort ();
+            break;
+    }
+    return new recording::memento_of_get_type (&target_builtins_ctxt, type);
+  }
   else
   {
     // Attempt to find an unqualified type when the current type has qualifiers.
@@ -1380,7 +1420,8 @@ jit_langhook_global_bindings_p (void)
 static tree
 jit_langhook_pushdecl (tree decl ATTRIBUTE_UNUSED)
 {
-  gcc_unreachable ();
+  /* Do nothing to avoid crashing on some targets.  */
+  return NULL_TREE;
 }
 
 static tree