Allow setting built-in options from cross/native files

This is like the project options, but for meson builtin options.

The only real differences here have to do with the differences between
meson builtin options and project options. Some meson options can be set
on a per-machine basis (build.pkg_config_path vs pkg_config_path) others
can be set on a per-subproject basis, but should inherit the parent
setting.

16 files changed, 307 insertions, 38 deletions

diff --git a/cross/armcc.txt b/cross/armcc.txt
index c884ffa..ae65c9e 100644
--- a/cross/armcc.txt
+++ b/cross/armcc.txt
@@ -7,7 +7,7 @@ cpp = 'armcc'
 ar = 'armar'
 strip = 'armar'
 
-[properties]
+[built-in options]
 # The '--cpu' option with the appropriate target type should be mentioned
 # to cross compile c/c++ code with armcc,.
 c_args      = ['--cpu=Cortex-M0plus']
diff --git a/cross/armclang-linux.txt b/cross/armclang-linux.txt
index 6df78d6..10f6fa4 100644
--- a/cross/armclang-linux.txt
+++ b/cross/armclang-linux.txt
@@ -12,7 +12,7 @@
 # Armcc is only available in toolchain version 5.
 # Armclang is only available in toolchain version 6.
 # Start shell with /opt/arm/developmentstudio-2019.0/bin/suite_exec zsh
-# Now the compilers will work. 
+# Now the compilers will work.
 
 [binaries]
 # we could set exe_wrapper = qemu-arm-static but to test the case
@@ -24,8 +24,7 @@ ar = '/opt/arm/developmentstudio-2019.0/sw/ARMCompiler6.12/bin/armar'
 #strip = '/usr/arm-linux-gnueabihf/bin/strip'
 #pkgconfig = '/usr/bin/arm-linux-gnueabihf-pkg-config'
 
-[properties]
-
+[built-in options]
 c_args = ['--target=aarch64-arm-none-eabi']
 
 [host_machine]
diff --git a/cross/armclang.txt b/cross/armclang.txt
index 955b7ef..6146e0d 100644
--- a/cross/armclang.txt
+++ b/cross/armclang.txt
@@ -7,7 +7,7 @@ cpp = 'armclang'
 ar = 'armar'
 strip = 'armar'
 
-[properties]
+[built-in options]
 # The '--target', '-mcpu' options with the appropriate values should be mentioned
 # to cross compile c/c++ code with armclang.
 c_args      = ['--target=arm-arm-none-eabi', '-mcpu=cortex-m0plus']
diff --git a/cross/c2000.txt b/cross/c2000.txt
index e624f25..61c0310 100644
--- a/cross/c2000.txt
+++ b/cross/c2000.txt
@@ -12,8 +12,7 @@ cpu_family = 'c2000'
 cpu = 'c28x'
 endian = 'little'
 
-[properties]
-needs_exe_wrapper = true
+[built-in options]
 c_args = [
     '-v28',
     '-ml',
@@ -24,3 +23,6 @@ c_link_args = [
     '\f28004x_flash.cmd']
 cpp_args = []
 cpp_link_args = []
+
+[properties]
+needs_exe_wrapper = true
diff --git a/cross/ccrx.txt b/cross/ccrx.txt
index 097ec06..f1b536c 100644
--- a/cross/ccrx.txt
+++ b/cross/ccrx.txt
@@ -7,7 +7,7 @@ cpp = 'ccrx'
 ar = 'rlink'
 strip = 'rlink'
 
-[properties]
+[built-in options]
 # The '--cpu' option with the appropriate target type should be mentioned
 # to cross compile c/c++ code with ccrx,.
 c_args      = ['-cpu=rx600']
diff --git a/cross/iphone.txt b/cross/iphone.txt
index e714da5..9659407 100644
--- a/cross/iphone.txt
+++ b/cross/iphone.txt
@@ -8,14 +8,14 @@ cpp = 'clang++'
 ar = 'ar'
 strip = 'strip'
 
-[properties]
-root = '/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer'
-
+[built-in options]
 c_args = ['-arch', 'armv7', '-miphoneos-version-min=8.0', '-isysroot', '/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS8.4.sdk']
 cpp_args = ['-arch', 'armv7', '-miphoneos-version-min=8.0', '-isysroot', '/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS8.4.sdk']
 c_link_args = ['-arch', 'armv7', '-miphoneos-version-min=8.0', '-isysroot', '/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS8.4.sdk']
 cpp_link_args = ['-arch', 'armv7', '-miphoneos-version-min=8.0', '-isysroot', '/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS8.4.sdk']
 
+[properties]
+root = '/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer'
 has_function_printf = true
 has_function_hfkerhisadf = false
 
diff --git a/cross/tvos.txt b/cross/tvos.txt
index dd6d5c1..833f04b 100644
--- a/cross/tvos.txt
+++ b/cross/tvos.txt
@@ -8,14 +8,15 @@ cpp = 'clang++'
 ar = 'ar'
 strip = 'strip'
 
-[properties]
-root = '/Applications/Xcode.app/Contents/Developer/Platforms/AppleTVOS.platform/Developer'
-
+[built-in options]
 c_args = ['-arch', 'arm64', '-mtvos-version-min=12.0', '-isysroot', '/Applications/Xcode.app/Contents/Developer/Platforms/AppleTVOS.platform/Developer/SDKs/AppleTVOS.sdk']
 cpp_args = ['-arch', 'arm64', '-mtvos-version-min=12.0', '-isysroot', '/Applications/Xcode.app/Contents/Developer/Platforms/AppleTVOS.platform/Developer/SDKs/AppleTVOS.sdk']
 c_link_args = ['-arch', 'arm64', '-mtvos-version-min=12.0', '-isysroot', '/Applications/Xcode.app/Contents/Developer/Platforms/AppleTVOS.platform/Developer/SDKs/AppleTVOS.sdk']
 cpp_link_args = ['-arch', 'arm64', '-mtvos-version-min=12.0', '-isysroot', '/Applications/Xcode.app/Contents/Developer/Platforms/AppleTVOS.platform/Developer/SDKs/AppleTVOS.sdk']
 
+[properties]
+root = '/Applications/Xcode.app/Contents/Developer/Platforms/AppleTVOS.platform/Developer'
+
 has_function_printf = true
 has_function_hfkerhisadf = false
 
diff --git a/cross/ubuntu-armhf.txt b/cross/ubuntu-armhf.txt
index 4600c22..69e0c86 100644
--- a/cross/ubuntu-armhf.txt
+++ b/cross/ubuntu-armhf.txt
@@ -9,12 +9,14 @@ strip = '/usr/arm-linux-gnueabihf/bin/strip'
 pkgconfig = '/usr/bin/arm-linux-gnueabihf-pkg-config'
 ld = '/usr/bin/arm-linux/gnueabihf-ld'
 
-[properties]
-root = '/usr/arm-linux-gnueabihf'
+[built-in options]
 # Used in unit test '140 get define'
 c_args = ['-DMESON_TEST_ISSUE_1665=1']
 cpp_args = '-DMESON_TEST_ISSUE_1665=1'
 
+[properties]
+root = '/usr/arm-linux-gnueabihf'
+
 has_function_printf = true
 has_function_hfkerhisadf = false
 
diff --git a/cross/wasm.txt b/cross/wasm.txt
index a43636f..f2d0cd7 100644
--- a/cross/wasm.txt
+++ b/cross/wasm.txt
@@ -3,8 +3,7 @@ c = '/home/jpakkane/emsdk/fastcomp/emscripten/emcc'
 cpp = '/home/jpakkane/emsdk/fastcomp/emscripten/em++'
 ar = '/home/jpakkane/emsdk/fastcomp/emscripten/emar'
 
-[properties]
-
+[built-in options]
 c_args = ['-s', 'WASM=1', '-s', 'EXPORT_ALL=1']
 c_link_args = ['-s','EXPORT_ALL=1']
 cpp_args = ['-s', 'WASM=1', '-s', 'EXPORT_ALL=1']
diff --git a/cross/xc16.txt b/cross/xc16.txt
index 1e67362..c66889d 100644
--- a/cross/xc16.txt
+++ b/cross/xc16.txt
@@ -14,6 +14,8 @@ endian = 'little'
 
 [properties]
 needs_exe_wrapper = true
+
+[built-in options]
 c_args = [
     '-c',
     '-mcpu=33EP64MC203',
diff --git a/docs/markdown/Machine-files.md b/docs/markdown/Machine-files.md
index ae0219b..e3de808 100644
--- a/docs/markdown/Machine-files.md
+++ b/docs/markdown/Machine-files.md
@@ -13,6 +13,7 @@ The following sections are allowed:
 - paths
 - properties
 - project options
+- built-in options
 
 ### constants
 
@@ -158,17 +159,23 @@ command line will override any options in the native file. For example, passing
 
 In addition to special data that may be specified in cross files, this
 section may contain random key value pairs accessed using the
-`meson.get_external_property`, or `meson.get_cross_property`.
+`meson.get_external_property()`, or `meson.get_cross_property()`.
+
+*Changed in 0.55.0* putting `<lang>_args` and `<lang>_link_args` in the
+properties section has been deprecated, and should be put in the built-in
+options section.
 
 ### Project specific options
 
-*New in 0.54.0*
+*New in 0.55.0*
+
+Path options are not allowed, those must be set in the `[paths]` section.
 
-Being able to set project specific options in a native or cross files can be
+Being able to set project specific options in a cross or native file can be
 done using the `[project options]` section of the specific file (if doing a
 cross build the options from the native file will be ignored)
 
-For setting options in supbprojects use the `<subproject>:project options`
+For setting options in subprojects use the `[<subproject>:project options]`
 section instead.
 
 ```ini
@@ -179,6 +186,47 @@ build-tests = true
 build-tests = false
 ```
 
+
+### Meson built-in options
+
+Meson built-in options can be set the same way:
+
+```ini
+[built-in options]
+c_std = 'c99'
+```
+
+You can set some meson built-in options on a per-subproject basis, such as
+`default_library` and `werror`. The order of precedence is:
+1) Command line
+2) Machine file
+3) Build system definitions
+
+```ini
+[zlib:built-in options]
+default_library = 'static'
+werror = false
+```
+
+Options set on a per-subproject basis will inherit the
+option from the parent if the parent has a setting but the subproject
+doesn't, even when there is a default set meson language.
+
+```ini
+[built-in options]
+default_library = 'static'
+```
+
+will make subprojects use default_library as static.
+
+Some options can be set on a per-machine basis (in other words, the value of
+the build machine can be different than the host machine in a cross compile).
+In these cases the values from both a cross file and a native file are used.
+
+An incomplete list of options is:
+- pkg_config_path
+- cmake_prefix_path
+
 ## Loading multiple machine files
 
 Native files allow layering (cross files can be layered since meson 0.52.0).
diff --git a/docs/markdown/snippets/project_options_in_machine_files.md b/docs/markdown/snippets/project_options_in_machine_files.md
index 78b129a..8dab951 100644
--- a/docs/markdown/snippets/project_options_in_machine_files.md
+++ b/docs/markdown/snippets/project_options_in_machine_files.md
@@ -1,4 +1,4 @@
-## Project options can be set in native or cross files
+## Project and built-in options can be set in native or cross files
 
 A new set of sections has been added to the cross and native files, `[project
 options]` and `[<subproject_name>:project options]`, where `subproject_name`
@@ -35,3 +35,18 @@ Subproject options are assigned like this:
 [zlib:project options]
 foo = 'some val'
 ```
+
+Additionally meson level options can be set in the same way, using the
+`[built-in options]` section.
+
+```ini
+[built-in options]
+c_std = 'c99'
+```
+
+These options can also be set on a per-subproject basis, although only
+`default_library` and `werror` can currently be set:
+```ini
+[zlib:built-in options]
+default_library = 'static'
+```
diff --git a/mesonbuild/coredata.py b/mesonbuild/coredata.py
index 3330ae5..0cac029 100644
--- a/mesonbuild/coredata.py
+++ b/mesonbuild/coredata.py
@@ -361,15 +361,15 @@ class CoreData:
         self.install_guid = str(uuid.uuid4()).upper()
         self.target_guids = {}
         self.version = version
-        self.builtins = {} # : OptionDictType
+        self.builtins = {} # type: OptionDictType
         self.builtins_per_machine = PerMachine({}, {})
-        self.backend_options = {} # : OptionDictType
-        self.user_options = {} # : OptionDictType
+        self.backend_options = {} # type: OptionDictType
+        self.user_options = {} # type: OptionDictType
         self.compiler_options = PerMachine(
             defaultdict(dict),
             defaultdict(dict),
         ) # : PerMachine[T.defaultdict[str, OptionDictType]]
-        self.base_options = {} # : OptionDictType
+        self.base_options = {} # type: OptionDictType
         self.cross_files = self.__load_config_files(options, scratch_dir, 'cross')
         self.compilers = PerMachine(OrderedDict(), OrderedDict())
 
@@ -743,19 +743,28 @@ class CoreData:
             mlog.warning('Recommend using either -Dbuildtype or -Doptimization + -Ddebug. '
                          'Using both is redundant since they override each other. '
                          'See: https://mesonbuild.com/Builtin-options.html#build-type-options')
+
         cmd_line_options = OrderedDict()
-        # Set project default_options as if they were passed to the cmdline.
+        # Set default options as if they were passed to the command line.
         # Subprojects can only define default for user options and not yielding
         # builtin option.
         from . import optinterpreter
-        for k, v in default_options.items():
+        for k, v in chain(default_options.items(), env.meson_options.host.get('', {}).items()):
             if subproject:
                 if (k not in builtin_options or builtin_options[k].yielding) \
                         and optinterpreter.is_invalid_name(k, log=False):
                     continue
-                k = subproject + ':' + k
             cmd_line_options[k] = v
 
+        # IF the subproject options comes from a machine file, then we need to
+        # set the option as subproject:option
+        if subproject:
+            for k, v in env.meson_options.host.get(subproject, {}).items():
+                if (k not in builtin_options or builtin_options[k].yielding) \
+                        and optinterpreter.is_invalid_name(k, log=False):
+                    continue
+                cmd_line_options['{}:{}'.format(subproject, k)] = v
+
         # load the values for user options out of the appropriate machine file,
         # then overload the command line
         for k, v in env.user_options.get(subproject, {}).items():
@@ -768,8 +777,32 @@ class CoreData:
             if v is not None:
                 cmd_line_options[k] = v
 
+        from .compilers import all_languages
+        # Report that [properties]c_args
+        for lang in all_languages:
+            for args in ['{}_args'.format(lang), '{}_link_args'.format(lang)]:
+                msg = ('{} in the [properties] section of the machine file is deprecated, '
+                       'use the [built-in options] section.')
+                if args in env.properties.host or args in env.properties.build:
+                    mlog.deprecation(msg.format(args))
+
+        # Currently we don't support any options that are both per-subproject
+        # and per-machine, but when we do this will need to account for that.
+        # For cross builds we need to get the build specifc options
+        if env.meson_options.host != env.meson_options.build and subproject in env.meson_options.build:
+            for k in builtin_options_per_machine.keys():
+                if k in env.meson_options.build[subproject]:
+                    cmd_line_options['build.{}'.format(k)] = env.meson_options.build[subproject][k]
+
+            # compiler options are always per-machine
+            for lang in all_languages:
+                prefix = '{}_'.format(lang)
+                for k in env.meson_options.build[subproject]:
+                    if k.startswith(prefix):
+                        cmd_line_options['build.{}'.format(k)] = env.meson_options.build[subproject][k]
+
         # Override all the above defaults using the command-line arguments
-        # actually passed to us
+        # actually passed to use
         cmd_line_options.update(env.cmd_line_options)
         env.cmd_line_options = cmd_line_options
 
diff --git a/mesonbuild/environment.py b/mesonbuild/environment.py
index c872aee..dc674fd 100644
--- a/mesonbuild/environment.py
+++ b/mesonbuild/environment.py
@@ -556,6 +556,9 @@ class Environment:
         # We only need one of these as project options are not per machine
         user_options = {}
 
+        # meson builtin options, as passed through cross or native files
+        meson_options = PerMachineDefaultable()
+
         ## Setup build machine defaults
 
         # Will be fully initialized later using compilers later.
@@ -568,14 +571,15 @@ class Environment:
 
         ## Read in native file(s) to override build machine configuration
 
-        def load_user_options():
+        def load_options(tag: str, store: T.Dict[str, T.Any]) -> None:
             for section in config.keys():
-                if section.endswith('project options'):
+                if section.endswith(tag):
                     if ':' in section:
                         project = section.split(':')[0]
                     else:
                         project = ''
-                    user_options[project] = config.get(section, {})
+                    store[project] = config.get(section, {})
+
 
         if self.coredata.config_files is not None:
             config = coredata.parse_machine_files(self.coredata.config_files)
@@ -586,7 +590,9 @@ class Environment:
             # Don't run this if there are any cross files, we don't want to use
             # the native values if we're doing a cross build
             if not self.coredata.cross_files:
-                load_user_options()
+                load_options('project options', user_options)
+            meson_options.build = {}
+            load_options('built-in options', meson_options.build)
 
         ## Read in cross file(s) to override host machine configuration
 
@@ -599,7 +605,9 @@ class Environment:
             if 'target_machine' in config:
                 machines.target = MachineInfo.from_literal(config['target_machine'])
             paths.host = Directories(**config.get('paths', {}))
-            load_user_options()
+            load_options('project options', user_options)
+            meson_options.host = {}
+            load_options('built-in options', meson_options.host)
 
         ## "freeze" now initialized configuration, and "save" to the class.
 
@@ -608,6 +616,16 @@ class Environment:
         self.properties = properties.default_missing()
         self.paths = paths.default_missing()
         self.user_options = user_options
+        self.meson_options = meson_options.default_missing()
+
+        # Ensure that no paths are passed via built-in options:
+        if '' in self.meson_options.host:
+            for each in coredata.BUILTIN_DIR_OPTIONS.keys():
+                # These are not per-subdirectory and probably never will be
+                if each in self.meson_options.host['']:
+                    raise EnvironmentException(
+                        'Invalid entry {} in [built-in options] section. '
+                        'Use the [paths] section instead.'.format(each))
 
         exe_wrapper = self.lookup_binary_entry(MachineChoice.HOST, 'exe_wrapper')
         if exe_wrapper is not None:
diff --git a/mesonbuild/interpreter.py b/mesonbuild/interpreter.py
index 45813c1..317793d 100644
--- a/mesonbuild/interpreter.py
+++ b/mesonbuild/interpreter.py
@@ -2791,6 +2791,7 @@ external dependencies (including libraries) must go to "dependencies".''')
 
         default_options = mesonlib.stringlistify(kwargs.get('default_options', []))
         default_options = coredata.create_options_dict(default_options)
+
         if dirname == '':
             raise InterpreterException('Subproject dir name must not be empty.')
         if dirname[0] == '.':
diff --git a/run_unittests.py b/run_unittests.py
index 9d96ce0..bce0bda 100755
--- a/run_unittests.py
+++ b/run_unittests.py
@@ -7672,8 +7672,10 @@ class NativeFileTests(BasePlatformTests):
             for section, entries in values.items():
                 f.write('[{}]\n'.format(section))
                 for k, v in entries.items():
-                    if isinstance(v, bool):
+                    if isinstance(v, (bool, int, float)):
                         f.write("{}={}\n".format(k, v))
+                    elif isinstance(v, list):
+                        f.write("{}=[{}]\n".format(k, ', '.join(["'{}'".format(w) for w in v])))
                     else:
                         f.write("{}='{}'\n".format(k, v))
         return filename
@@ -8047,6 +8049,108 @@ class NativeFileTests(BasePlatformTests):
         else:
             self.fail('Did not find werror in build options?')
 
+    def test_option_integer(self):
+        # Bools are allowed to be unquoted
+        testcase = os.path.join(self.common_test_dir, '1 trivial')
+        config = self.helper_create_native_file({'built-in options': {'unity_size': 100}})
+        self.init(testcase, extra_args=['--native-file', config])
+        configuration = self.introspect('--buildoptions')
+        for each in configuration:
+            # Test that no-per subproject options are inherited from the parent
+            if 'unity_size' in each['name']:
+                self.assertEqual(each['value'], 100)
+                break
+        else:
+            self.fail('Did not find unity_size in build options?')
+
+    def test_builtin_options(self):
+        testcase = os.path.join(self.common_test_dir, '2 cpp')
+        config = self.helper_create_native_file({'built-in options': {'cpp_std': 'c++14'}})
+
+        self.init(testcase, extra_args=['--native-file', config])
+        configuration = self.introspect('--buildoptions')
+        for each in configuration:
+            if each['name'] == 'cpp_std':
+                self.assertEqual(each['value'], 'c++14')
+                break
+        else:
+            self.fail('Did not find werror in build options?')
+
+    def test_builtin_options_subprojects(self):
+        testcase = os.path.join(self.common_test_dir, '102 subproject subdir')
+        config = self.helper_create_native_file({'built-in options': {'default_library': 'both', 'c_args': ['-Dfoo']}, 'sub:built-in options': {'default_library': 'static'}})
+
+        self.init(testcase, extra_args=['--native-file', config])
+        configuration = self.introspect('--buildoptions')
+        found = 0
+        for each in configuration:
+            # Test that no-per subproject options are inherited from the parent
+            if 'c_args' in each['name']:
+                # This path will be hit twice, once for build and once for host,
+                self.assertEqual(each['value'], ['-Dfoo'])
+                found += 1
+            elif each['name'] == 'default_library':
+                self.assertEqual(each['value'], 'both')
+                found += 1
+            elif each['name'] == 'sub:default_library':
+                self.assertEqual(each['value'], 'static')
+                found += 1
+        self.assertEqual(found, 4, 'Did not find all three sections')
+
+    def test_builtin_options_subprojects_overrides_buildfiles(self):
+        # If the buildfile says subproject(... default_library: shared), ensure that's overwritten
+        testcase = os.path.join(self.common_test_dir, '230 persubproject options')
+        config = self.helper_create_native_file({'sub2:built-in options': {'default_library': 'shared'}})
+
+        with self.assertRaises(subprocess.CalledProcessError) as cm:
+            self.init(testcase, extra_args=['--native-file', config])
+            self.assertIn(cm.exception.stdout, 'Parent should override default_library')
+
+    def test_builtin_options_subprojects_inherits_parent_override(self):
+        # If the buildfile says subproject(... default_library: shared), ensure that's overwritten
+        testcase = os.path.join(self.common_test_dir, '230 persubproject options')
+        config = self.helper_create_native_file({'built-in options': {'default_library': 'both'}})
+
+        with self.assertRaises(subprocess.CalledProcessError) as cm:
+            self.init(testcase, extra_args=['--native-file', config])
+            self.assertIn(cm.exception.stdout, 'Parent should override default_library')
+
+    def test_builtin_options_compiler_properties(self):
+        # the properties section can have lang_args, and those need to be
+        # overwritten by the built-in options
+        testcase = os.path.join(self.common_test_dir, '1 trivial')
+        config = self.helper_create_native_file({
+            'built-in options': {'c_args': ['-DFOO']},
+            'properties': {'c_args': ['-DBAR']},
+        })
+
+        self.init(testcase, extra_args=['--native-file', config])
+        configuration = self.introspect('--buildoptions')
+        for each in configuration:
+            if each['name'] == 'c_args':
+                self.assertEqual(each['value'], ['-DFOO'])
+                break
+        else:
+            self.fail('Did not find c_args in build options?')
+
+    def test_builtin_options_compiler_properties_legacy(self):
+        # The legacy placement in properties is still valid if a 'built-in
+        # options' setting is present, but doesn't have the lang_args
+        testcase = os.path.join(self.common_test_dir, '1 trivial')
+        config = self.helper_create_native_file({
+            'built-in options': {'default_library': 'static'},
+            'properties': {'c_args': ['-DBAR']},
+        })
+
+        self.init(testcase, extra_args=['--native-file', config])
+        configuration = self.introspect('--buildoptions')
+        for each in configuration:
+            if each['name'] == 'c_args':
+                self.assertEqual(each['value'], ['-DBAR'])
+                break
+        else:
+            self.fail('Did not find c_args in build options?')
+
 
 class CrossFileTests(BasePlatformTests):
 
@@ -8266,9 +8370,54 @@ class CrossFileTests(BasePlatformTests):
         testcase = os.path.join(self.common_test_dir, '43 options')
         config = self.helper_create_cross_file({'project options': {'testoption': 'some other value'}})
         with self.assertRaises(subprocess.CalledProcessError) as cm:
-            self.init(testcase, extra_args=['--native-file', config])
+            self.init(testcase, extra_args=['--cross-file', config])
             self.assertRegex(cm.exception.stdout, r'Incorrect value to [a-z]+ option')
 
+    def test_builtin_options(self):
+        testcase = os.path.join(self.common_test_dir, '2 cpp')
+        config = self.helper_create_cross_file({'built-in options': {'cpp_std': 'c++14'}})
+
+        self.init(testcase, extra_args=['--cross-file', config])
+        configuration = self.introspect('--buildoptions')
+        for each in configuration:
+            if each['name'] == 'cpp_std':
+                self.assertEqual(each['value'], 'c++14')
+                break
+        else:
+            self.fail('No c++ standard set?')
+
+    def test_builtin_options_per_machine(self):
+        """Test options that are allowed to be set on a per-machine basis.
+
+        Such options could be passed twice, once for the build machine, and
+        once for the host machine. I've picked pkg-config path, but any would
+        do that can be set for both.
+        """
+        testcase = os.path.join(self.common_test_dir, '2 cpp')
+        cross = self.helper_create_cross_file({'built-in options': {'pkg_config_path': '/cross/path', 'cpp_std': 'c++17'}})
+        native = self.helper_create_cross_file({'built-in options': {'pkg_config_path': '/native/path', 'cpp_std': 'c++14'}})
+
+        self.init(testcase, extra_args=['--cross-file', cross, '--native-file', native])
+        configuration = self.introspect('--buildoptions')
+        found = 0
+        for each in configuration:
+            if each['name'] == 'pkg_config_path':
+                self.assertEqual(each['value'], ['/cross/path'])
+                found += 1
+            elif each['name'] == 'cpp_std':
+                self.assertEqual(each['value'], 'c++17')
+                found += 1
+            elif each['name'] == 'build.pkg_config_path':
+                self.assertEqual(each['value'], ['/native/path'])
+                found += 1
+            elif each['name'] == 'build.cpp_std':
+                self.assertEqual(each['value'], 'c++14')
+                found += 1
+
+            if found == 4:
+                break
+        self.assertEqual(found, 4, 'Did not find all sections.')
+
 
 class TAPParserTests(unittest.TestCase):
     def assert_test(self, events, **kwargs):