Never access environment.properties downstream

Instead use coredata.compiler_options.<machine>. This brings the cross
and native code paths closer together, since both now use that.

Command line options are interpreted just as before, for backwards
compatibility. This does introduce some funny conditionals. In the
future, I'd like to change the interpretation of command line options so

 - The logic is cross-agnostic, i.e. there are no conditions affected by
   `is_cross_build()`.

 - Compiler args for both the build and host machines can always be
   controlled by the command line.

 - Compiler args for both machines can always be controlled separately.

1 files changed, 54 insertions, 34 deletions

diff --git a/mesonbuild/coredata.py b/mesonbuild/coredata.py
index b2b9e91..3ce272e 100644
--- a/mesonbuild/coredata.py
+++ b/mesonbuild/coredata.py
@@ -19,7 +19,8 @@ from itertools import chain
 from pathlib import PurePath
 from collections import OrderedDict
 from .mesonlib import (
-    MesonException, default_libdir, default_libexecdir, default_prefix
+    MesonException, MachineChoice, PerMachine,
+    default_libdir, default_libexecdir, default_prefix
 )
 from .wrap import WrapMode
 import ast
@@ -261,9 +262,9 @@ class CoreData:
         self.init_builtins()
         self.backend_options = {}
         self.user_options = {}
-        self.compiler_options = {}
+        self.compiler_options = PerMachine({}, {}, {})
         self.base_options = {}
-        self.external_preprocess_args = {} # CPPFLAGS only
+        self.external_preprocess_args = PerMachine({}, {}, {}) # CPPFLAGS only
         self.cross_file = self.__load_cross_file(options.cross_file)
         self.compilers = OrderedDict()
         self.cross_compilers = OrderedDict()
@@ -457,16 +458,18 @@ class CoreData:
             mode = 'custom'
         self.builtins['buildtype'].set_value(mode)
 
+    def get_all_compiler_options(self):
+        # TODO think about cross and command-line interface. (Only .build is mentioned here.)
+        yield self.compiler_options.build
+
     def _get_all_nonbuiltin_options(self):
         yield self.backend_options
         yield self.user_options
-        yield self.compiler_options
+        yield from self.get_all_compiler_options()
         yield self.base_options
 
     def get_all_options(self):
-        return chain(
-            iter([self.builtins]),
-            self._get_all_nonbuiltin_options())
+        return chain([self.builtins], self._get_all_nonbuiltin_options())
 
     def validate_option_value(self, option_name, override_value):
         for opts in self.get_all_options():
@@ -475,14 +478,14 @@ class CoreData:
                 return opt.validate_value(override_value)
         raise MesonException('Tried to validate unknown option %s.' % option_name)
 
-    def get_external_args(self, lang):
-        return self.compiler_options[lang + '_args'].value
+    def get_external_args(self, for_machine: MachineChoice, lang):
+        return self.compiler_options[for_machine][lang + '_args'].value
 
-    def get_external_link_args(self, lang):
-        return self.compiler_options[lang + '_link_args'].value
+    def get_external_link_args(self, for_machine: MachineChoice, lang):
+        return self.compiler_options[for_machine][lang + '_link_args'].value
 
-    def get_external_preprocess_args(self, lang):
-        return self.external_preprocess_args[lang]
+    def get_external_preprocess_args(self, for_machine: MachineChoice, lang):
+        return self.external_preprocess_args[for_machine][lang]
 
     def merge_user_options(self, options):
         for (name, value) in options.items():
@@ -493,7 +496,7 @@ class CoreData:
                 if type(oldval) != type(value):
                     self.user_options[name] = value
 
-    def set_options(self, options, subproject=''):
+    def set_options(self, options, subproject='', warn_unknown=True):
         # Set prefix first because it's needed to sanitize other options
         prefix = self.builtins['prefix'].value
         if 'prefix' in options:
@@ -517,8 +520,7 @@ class CoreData:
                         break
                 else:
                     unknown_options.append(k)
-
-        if unknown_options:
+        if unknown_options and warn_unknown:
             unknown_options = ', '.join(sorted(unknown_options))
             sub = 'In subproject {}: '.format(subproject) if subproject else ''
             mlog.warning('{}Unknown options: "{}"'.format(sub, unknown_options))
@@ -553,36 +555,54 @@ class CoreData:
 
         self.set_options(options, subproject)
 
-    def process_new_compilers(self, lang: str, comp, cross_comp, cmd_line_options):
+    def process_new_compilers(self, lang: str, comp, cross_comp, env):
         from . import compilers
+
         self.compilers[lang] = comp
-        # Native compiler always exist so always add its options.
-        new_options = comp.get_options()
         if cross_comp is not None:
             self.cross_compilers[lang] = cross_comp
-            new_options.update(cross_comp.get_options())
+
+        # Native compiler always exist so always add its options.
+        new_options_for_build = comp.get_options()
+        preproc_flags_for_build = comp.get_preproc_flags()
+        if cross_comp is not None:
+            new_options_for_host = cross_comp.get_options()
+            preproc_flags_for_host = cross_comp.get_preproc_flags()
+        else:
+            new_options_for_host = comp.get_options()
+            preproc_flags_for_host = comp.get_preproc_flags()
+
+        opts_machines_list = [
+            (new_options_for_build, preproc_flags_for_build, MachineChoice.BUILD),
+            (new_options_for_host, preproc_flags_for_host, MachineChoice.HOST),
+        ]
 
         optprefix = lang + '_'
-        for k, o in new_options.items():
-            if not k.startswith(optprefix):
-                raise MesonException('Internal error, %s has incorrect prefix.' % k)
-            if k in cmd_line_options:
-                o.set_value(cmd_line_options[k])
-            self.compiler_options.setdefault(k, o)
-
-        # Unlike compiler and linker flags, preprocessor flags are not in
-        # compiler_options because they are not visible to user.
-        preproc_flags = comp.get_preproc_flags()
-        preproc_flags = shlex.split(preproc_flags)
-        self.external_preprocess_args.setdefault(lang, preproc_flags)
+        for new_options, preproc_flags, for_machine in opts_machines_list:
+            for k, o in new_options.items():
+                if not k.startswith(optprefix):
+                    raise MesonException('Internal error, %s has incorrect prefix.' % k)
+                if k in env.properties[for_machine]:
+                    # Get from configuration files.
+                    o.set_value(env.properties[for_machine][k])
+                if (env.machines.matches_build_machine(for_machine) and
+                        k in env.cmd_line_options):
+                    # TODO think about cross and command-line interface.
+                    o.set_value(env.cmd_line_options[k])
+                self.compiler_options[for_machine].setdefault(k, o)
+
+            # Unlike compiler and linker flags, preprocessor flags are not in
+            # compiler_options because they are not visible to user.
+            preproc_flags = shlex.split(preproc_flags)
+            self.external_preprocess_args[for_machine].setdefault(lang, preproc_flags)
 
         enabled_opts = []
         for optname in comp.base_options:
             if optname in self.base_options:
                 continue
             oobj = compilers.base_options[optname]
-            if optname in cmd_line_options:
-                oobj.set_value(cmd_line_options[optname])
+            if optname in env.cmd_line_options:
+                oobj.set_value(env.cmd_line_options[optname])
                 enabled_opts.append(optname)
             self.base_options[optname] = oobj
         self.emit_base_options_warnings(enabled_opts)