rename compile option 'ghdl.flags' to 'ghdl.a_flags'; keep 'ghdl.flag…

…s' as an alias and show a deprecation notice

docs/py/opts.rst

@@ -7,10 +7,13 @@ Compilation options allow customization of compilation behavior. Since simulator
 differing options available, generic options may be specified through this interface.
 The following compilation options are known.
 
-``ghdl.flags``
+``ghdl.a_flags``
    Extra arguments passed to ``ghdl -a`` command during compilation.
    Must be a list of strings.
 
+``ghdl.flags``
+  Deprecated alias of ``ghdl.a_flags``. It will be removed in future releases.
+
 ``incisive.irun_vhdl_flags``
    Extra arguments passed to the Incisive ``irun`` command when compiling VHDL files.
    Must be a list of strings.

vunit/sim_if/ghdl.py

@@ -14,6 +14,7 @@
 import subprocess
 import shlex
 from sys import stdout  # To avoid output catched in non-verbose mode
+from warnings import warn
 from ..exceptions import CompileError
 from ..ostools import Process
 from . import SimulatorInterface, ListOfStringOption, StringOption, BooleanOption
@@ -32,7 +33,10 @@ class GHDLInterface(SimulatorInterface):
     supports_gui_flag = True
     supports_colors_in_gui = True
 
-    compile_options = [ListOfStringOption("ghdl.flags")]
+    compile_options = [
+        ListOfStringOption("ghdl.a_flags"),
+        ListOfStringOption("ghdl.flags"),
+    ]
 
     sim_options = [
         ListOfStringOption("ghdl.sim_flags"),
@@ -213,7 +217,20 @@ def compile_vhdl_file_command(self, source_file):
         ]
         for library in self._project.get_libraries():
             cmd += ["-P%s" % library.directory]
-        cmd += source_file.compile_options.get("ghdl.flags", [])
+
+        a_flags = source_file.compile_options.get("ghdl.a_flags", [])
+        flags = source_file.compile_options.get("ghdl.flags", [])
+        if flags != []:
+            warn(
+                (
+                    "'ghdl.flags' is deprecated and it will removed in future releases; "
+                    "use 'ghdl.a_flags' instead"
+                ),
+                Warning,
+            )
+            a_flags += flags
+
+        cmd += a_flags
         cmd += [source_file.name]
         return cmd