test: Add test to Verify storage size for implicit struct declarations

Signed-off-by: Eugene Loh <eugene.loh@oracle.com
Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>
Reviewed-by: Kris Van Hees <kris.van.hees@oracle.com>

test/unittest/struct/tst.implicit_decl.d

@@ -0,0 +1,85 @@
+/*
+ * Oracle Linux DTrace.
+ * Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.
+ * Licensed under the Universal Permissive License v 1.0 as shown at
+ * http://oss.oracle.com/licenses/upl.
+ */
+
+/*
+ * ASSERTION: Verify assignments when structs are implicitly declared.
+ *
+ * SECTION: Structs and Unions/Structs
+ */
+
+#pragma D option quiet
+
+/*
+ * Declare some structs, including a struct of structs.
+ */
+
+struct coords {
+	int x, y;
+};
+struct particle {
+	struct coords position;
+	struct coords velocity;
+};
+
+/*
+ * Declare some global (uppercase) and clause-local (lowercase) variables.
+ * The "dummy" variables are declared just so we can test nonzero offsets.
+ */
+     struct coords   C_DUMMY, C_DECLD;
+this struct coords   c_dummy, c_decld;
+     struct particle P_DUMMY, P_DECLD;
+this struct particle p_dummy, p_decld;
+
+BEGIN {
+	/* Initialize the declared variables. */
+	      C_DECLD.x          = 11;
+	      C_DECLD.y          = 12;
+	      P_DECLD.position.x = 13;
+	      P_DECLD.position.y = 14;
+	      P_DECLD.velocity.x = 15;
+	      P_DECLD.velocity.y = 16;
+	this->c_decld.x          = 21;
+	this->c_decld.y          = 22;
+	this->p_decld.position.x = 23;
+	this->p_decld.position.y = 24;
+	this->p_decld.velocity.x = 25;
+	this->p_decld.velocity.y = 26;
+
+	/* These structs are declared implicitly via their first assignments. */
+
+	      C_IMPL1          =       C_DECLD;
+	this->c_impl1          = this->c_decld;
+	      C_IMPL2          = this->c_impl1;
+	this->c_impl2          =       C_IMPL1;
+
+	      P_IMPL1          =       P_DECLD;
+	this->p_impl1          = this->p_decld;
+	      P_IMPL2          = this->p_impl1;
+	this->p_impl2          =       P_IMPL1;
+
+	      P_IMPL2.velocity = this->c_impl2;
+	this->p_impl2.velocity =       C_IMPL2;
+
+	/* print results */
+
+	printf("%d %d %d %d %d %d %d %d\n",
+	          P_IMPL2.position.x,
+	          P_IMPL2.position.y,
+	          P_IMPL2.velocity.x,
+	          P_IMPL2.velocity.y,
+	    this->p_impl2.position.x,
+	    this->p_impl2.position.y,
+	    this->p_impl2.velocity.x,
+	    this->p_impl2.velocity.y);
+
+	exit(0);
+}
+
+ERROR
+{
+	exit(1);
+}

test/unittest/struct/tst.implicit_decl.r

@@ -0,0 +1,2 @@
+23 24 11 12 13 14 21 22
+