Added tests for different cases

Added cases for union types, for anonymous structs and for volatile
variables (as opposed to const variables). Also added test for verifying
the dump C output

Author: thk123

regression/goto-instrument/const-struct2/main.c

@@ -0,0 +1,10 @@
+
+int main()
+{
+  const struct struct_tag_name {
+  int x;
+  float y;
+  } my_struct_var = {.x =  1, .y = 3.15};
+  const double z = 4;
+  return 0;
+}

regression/goto-instrument/const-struct2/test.desc

@@ -0,0 +1,9 @@
+CORE
+main.c
+--show-symbol-table
+^Type\.*: const struct struct_tag_name$
+^Type\.*: const double$
+^EXIT=0$
+^SIGNAL=0$
+--
+^warning: ignoring

regression/goto-instrument/const-struct3/main.c

@@ -0,0 +1,13 @@
+
+struct struct_tag_name
+{
+	int x;
+	float y;
+};
+
+int main()
+{
+  const struct struct_tag_name my_struct_var = {.x =  1, .y = 3.15};
+  const double z = 4;
+  return 0;
+}

regression/goto-instrument/const-struct3/test.desc

@@ -0,0 +1,9 @@
+CORE
+main.c
+--dump-c
+^\s*const struct struct_tag_name my_struct_var
+^\s*const double z
+^EXIT=0$
+^SIGNAL=0$
+--
+^warning: ignoring

regression/goto-instrument/const-union1/main.c

@@ -0,0 +1,13 @@
+
+union union_tag_name
+{
+	int x;
+	float y;
+};
+
+int main()
+{
+  const union union_tag_name my_union_var = {.y = 3.15};
+  const double z = 4;
+  return 0;
+}

regression/goto-instrument/const-union1/test.desc

@@ -0,0 +1,9 @@
+CORE
+main.c
+--show-symbol-table
+^Type\.*: const union union_tag_name$
+^Type\.*: const double$
+^EXIT=0$
+^SIGNAL=0$
+--
+^warning: ignoring

regression/goto-instrument/volatile-struct1/main.c

@@ -0,0 +1,13 @@
+
+struct struct_tag_name
+{
+	int x;
+	float y;
+};
+
+int main()
+{
+  volatile struct struct_tag_name my_struct_var = {.x =  1, .y = 3.15};
+  const double z = 4;
+  return 0;
+}

regression/goto-instrument/volatile-struct1/test.desc

@@ -0,0 +1,9 @@
+CORE
+main.c
+--show-symbol-table
+^Type\.*: volatile struct struct_tag_name$
+^Type\.*: const double$
+^EXIT=0$
+^SIGNAL=0$
+--
+^warning: ignoring