gdb/python: add void_type () method to gdb.Architecture object

This commit adds a new method to Python architecture objects that
returns a void type for that architecture.

This will be useful later to create types for function symbols created
using Python extension code.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>

gdb/NEWS

@@ -88,6 +88,9 @@
 
   ** Added gdb.Symbol.domain.  Contains the domain of the symbol.
 
+  ** Added gdb.Architecture.void_type. Returns a gdb.Type representing "void"
+     type for that architecture.
+
 * Debugger Adapter Protocol changes
 
   ** The "scopes" request will now return a scope holding global

gdb/doc/python.texi

@@ -7090,6 +7090,10 @@ If the indicated type cannot be found, this function will throw a
 @code{ValueError} exception.
 @end defun
 
+@defun Architecture.void_type ()
+This function returns a void type.
+@end defun
+
 @anchor{gdbpy_architecture_registers}
 @defun Architecture.registers (@r{[} reggroup @r{]})
 Return a @code{gdb.RegisterDescriptorIterator} (@pxref{Registers In

gdb/python/py-arch.c

@@ -318,6 +318,18 @@ archpy_integer_type (PyObject *self, PyObject *args, PyObject *kw)
   return type_to_type_object (type);
 }
 
+/* Implementation of gdb.void_type.  */
+static PyObject *
+archpy_void_type (PyObject *self, PyObject *args)
+{
+  struct gdbarch *gdbarch;
+  ARCHPY_REQUIRE_VALID (self, gdbarch);
+
+  builtin_type (gdbarch);
+
+  return type_to_type_object (builtin_type (gdbarch)->builtin_void);
+}
+
 /* __repr__ implementation for gdb.Architecture.  */
 
 static PyObject *
@@ -383,6 +395,10 @@ END_PC." },
     "integer_type (size [, signed]) -> type\n\
 Return an integer Type corresponding to the given bitsize and signed-ness.\n\
 If not specified, the type defaults to signed." },
+  { "void_type", (PyCFunction) archpy_void_type,
+    METH_NOARGS,
+    "void_type () -> type\n\
+Return an void Type." },
   { "registers", (PyCFunction) archpy_registers,
     METH_VARARGS | METH_KEYWORDS,
     "registers ([ group-name ]) -> Iterator.\n\

gdb/testsuite/gdb.python/py-arch.exp

@@ -104,6 +104,10 @@ foreach_with_prefix test_data { {None None} \
 	"check 'signed' argument can handle non-bool type $bad_type"
 }
 
+gdb_test "python print(arch.void_type())" \
+    "void" \
+    "get void type"
+
 # Test for gdb.architecture_names().  First we're going to grab the
 # complete list of architecture names using the 'complete' command.
 set arch_names []