Fix crash when getting cuda options

We could have an OptionOverrideProxy of an OptionOverrideProxy,
recursively. This fix is a minimal subset of the refactoring I did in
https://github.com/mesonbuild/meson/pull/9394. Instead of faking
UserOption we can just do a shallow copy of one and set a new value on
it.

Fixes: #9448

mesonbuild/mesonlib/universal.py

@@ -28,6 +28,7 @@ from tempfile import TemporaryDirectory
 import typing as T
 import uuid
 import textwrap
+import copy
 
 from mesonbuild import mlog
 
@@ -61,7 +62,6 @@ __all__ = [
     'OptionKey',
     'dump_conf_header',
     'OptionOverrideProxy',
-    'OptionProxy',
     'OptionType',
     'OrderedSet',
     'PerMachine',
@@ -1919,16 +1919,6 @@ def run_once(func: T.Callable[..., _T]) -> T.Callable[..., _T]:
     return wrapper
 
 
-class OptionProxy(T.Generic[_T]):
-    def __init__(self, value: _T, choices: T.Optional[T.List[str]] = None):
-        self.value = value
-        self.choices = choices
-
-    def set_value(self, v: _T) -> None:
-        # XXX: should this be an error
-        self.value = v
-
-
 class OptionOverrideProxy(collections.abc.MutableMapping):
 
     '''Mimic an option list but transparently override selected option
@@ -1944,15 +1934,16 @@ class OptionOverrideProxy(collections.abc.MutableMapping):
         for o in options:
             self.options.update(o)
 
-    def __getitem__(self, key: 'OptionKey') -> T.Union['UserOption', OptionProxy]:
+    def __getitem__(self, key: 'OptionKey') -> T.Union['UserOption']:
         if key in self.options:
             opt = self.options[key]
             if key in self.overrides:
-                return OptionProxy(opt.validate_value(self.overrides[key]), getattr(opt, 'choices', None))
+                opt = copy.copy(opt)
+                opt.set_value(self.overrides[key])
             return opt
         raise KeyError('Option not found', key)
 
-    def __setitem__(self, key: 'OptionKey', value: T.Union['UserOption', OptionProxy]) -> None:
+    def __setitem__(self, key: 'OptionKey', value: T.Union['UserOption']) -> None:
         self.overrides[key] = value.value
 
     def __delitem__(self, key: 'OptionKey') -> None:

test cases/cuda/16 multistd/lib.cu

@@ -0,0 +1,3 @@
+int do_cuda_stuff() {
+  return 0;
+}

test cases/cuda/16 multistd/main.cu

@@ -7,6 +7,7 @@ auto cuda_devices(void) {
     return result;
 }
 
+int do_cuda_stuff();
 
 int main(void) {
     int n = cuda_devices();
@@ -16,5 +17,5 @@ int main(void) {
     }
 
     std::cout << "Found " << n << "Cuda devices.\n";
-    return 0;
+    return do_cuda_stuff();
 }

test cases/cuda/16 multistd/meson.build

@@ -2,6 +2,12 @@ project('C++-CUDA multi-std', 'cpp', 'cuda',
         version : '1.0.0',
         default_options : ['cpp_std=c++17', 'cuda_std=c++14'])
 
-exe = executable('prog', 'main.cu')
+# Regression test: Passing override_options used to cause a crash.
+# See https://github.com/mesonbuild/meson/issues/9448.
+libcpp11 = static_library('testcpp11', 'lib.cu',
+  override_options: ['cpp_std=c++11']
+)
+
+exe = executable('prog', 'main.cu', link_with: libcpp11)
 # The runtimes leak memory, so ignore it.
 test('cudatest', exe, env: ['ASAN_OPTIONS=detect_leaks=0'])