meson/rust: wrap `bindgen`s `wrap-static-fns` functionality

This way the `rust.bindgen` can generate a second output being a C file,
which contains wrapper functions for static inline ones.

This output file can then be compiled via C targets.

docs/markdown/Rust-module.md

@@ -57,6 +57,9 @@ It takes the following keyword arguments
 - `input`: a list of Files, Strings, or CustomTargets. The first element is
   the header bindgen will parse, additional elements are dependencies.
 - `output`: the name of the output rust file
+- `output_inline_wrapper`: the name of the optional output c file containing
+  wrappers for static inline function. This requires `bindgen-0.65` or
+  newer (*since 1.3.0*).
 - `include_directories`: A list of `include_directories` or `string` objects,
   these are passed to clang as `-I` arguments *(string since 1.0.0)*
 - `c_args`: a list of string arguments to pass to clang untouched

mesonbuild/modules/rust.py

@@ -9,7 +9,7 @@ import typing as T
 from mesonbuild.interpreterbase.decorators import FeatureNew
 
 from . import ExtensionModule, ModuleReturnValue, ModuleInfo
-from .. import mlog
+from .. import mesonlib, mlog
 from ..build import (BothLibraries, BuildTarget, CustomTargetIndex, Executable, ExtractedObjects, GeneratedList,
                      CustomTarget, InvalidArguments, Jar, StructuredSources, SharedLibrary)
 from ..compilers.compilers import are_asserts_disabled, lang_suffixes
@@ -19,6 +19,7 @@ from ..interpreter.type_checking import (
 )
 from ..interpreterbase import ContainerTypeInfo, InterpreterException, KwargInfo, typed_kwargs, typed_pos_args, noPosargs, permittedKwargs
 from ..mesonlib import File
+from ..programs import ExternalProgram
 
 if T.TYPE_CHECKING:
     from . import ModuleState
@@ -27,7 +28,7 @@ if T.TYPE_CHECKING:
     from ..interpreter import Interpreter
     from ..interpreter import kwargs as _kwargs
     from ..interpreter.interpreter import SourceInputs, SourceOutputs
-    from ..programs import ExternalProgram, OverrideProgram
+    from ..programs import OverrideProgram
     from ..interpreter.type_checking import SourcesVarargsType
 
     from typing_extensions import TypedDict, Literal
@@ -46,6 +47,7 @@ if T.TYPE_CHECKING:
         include_directories: T.List[IncludeDirs]
         input: T.List[SourceInputs]
         output: str
+        output_inline_wrapper: str
         dependencies: T.List[T.Union[Dependency, ExternalLibrary]]
         language: T.Optional[Literal['c', 'cpp']]
         bindgen_version: T.List[str]
@@ -196,6 +198,12 @@ class RustModule(ExtensionModule):
         KwargInfo('bindgen_version', ContainerTypeInfo(list, str), default=[], listify=True, since='1.4.0'),
         INCLUDE_DIRECTORIES.evolve(since_values={ContainerTypeInfo(list, str): '1.0.0'}),
         OUTPUT_KW,
+        KwargInfo(
+            'output_inline_wrapper',
+            str,
+            default='',
+            since='1.3.0',
+        ),
         DEPENDENCIES_KW.evolve(since='1.0.0'),
     )
     def bindgen(self, state: ModuleState, args: T.List, kwargs: FuncBindgen) -> ModuleReturnValue:
@@ -287,12 +295,27 @@ class RustModule(ExtensionModule):
         if std != 'none':
             clang_args.append(f'-std={std}')
 
+        inline_wrapper_args: T.List[str] = []
+        outputs = [kwargs['output']]
+        if kwargs['output_inline_wrapper']:
+            # Todo drop this isinstance once Executable supports version_compare
+            if isinstance(self._bindgen_bin, ExternalProgram):
+                if mesonlib.version_compare(self._bindgen_bin.get_version(), '< 0.65'):
+                    raise InterpreterException('\'output_inline_wrapper\' parameter of rust.bindgen requires bindgen-0.65 or newer')
+
+            outputs.append(kwargs['output_inline_wrapper'])
+            inline_wrapper_args = [
+                '--experimental', '--wrap-static-fns',
+                '--wrap-static-fns-path', os.path.join(state.environment.build_dir, '@OUTPUT1@')
+            ]
+
         cmd = self._bindgen_bin.get_command() + \
             [
                 '@INPUT@', '--output',
-                os.path.join(state.environment.build_dir, '@OUTPUT@')
+                os.path.join(state.environment.build_dir, '@OUTPUT0@')
             ] + \
-            kwargs['args'] + ['--'] + kwargs['c_args'] + clang_args + \
+            kwargs['args'] + inline_wrapper_args + ['--'] + \
+            kwargs['c_args'] + clang_args + \
             ['-MD', '-MQ', '@INPUT@', '-MF', '@DEPFILE@']
 
         target = CustomTarget(
@@ -302,7 +325,7 @@ class RustModule(ExtensionModule):
             state.environment,
             cmd,
             [header],
-            [kwargs['output']],
+            outputs,
             depfile='@PLAINNAME@.d',
             extra_depends=depends,
             depend_files=depend_files,
@@ -310,7 +333,7 @@ class RustModule(ExtensionModule):
             description='Generating bindings for Rust {}',
         )
 
-        return ModuleReturnValue([target], [target])
+        return ModuleReturnValue(target, [target])
 
     # Allow a limited set of kwargs, but still use the full set of typed_kwargs()
     # because it could be setting required default values.