Tests: Add multithreading attribute checks (#3748)

Makefile.in

@@ -397,6 +397,7 @@ PY_PROGRAMS = \
 	src/flexfix \
 	src/vlcovgen \
 	test_regress/t/*.pf \
+	nodist/clang_check_attributes \
 	nodist/code_coverage \
 	nodist/dot_importer \
 	nodist/fuzzer/actual_fail \

ci/ci-install.bash

@@ -93,6 +93,11 @@ elif [ "$CI_BUILD_STAGE_NAME" = "test" ]; then
     sudo apt-get update
     # libfl-dev needed for internal coverage's test runs
     sudo apt-get install gdb gtkwave lcov libfl-dev ccache
+    # Required for test_regress/t/t_dist_attributes.pl
+    if [ "$CI_RUNS_ON" = "ubuntu-22.04" ]; then
+      sudo apt-get install libclang-dev
+      pip3 install clang==14.0
+    fi
     if [ "$CI_RUNS_ON" = "ubuntu-20.04" ] || [ "$CI_RUNS_ON" = "ubuntu-22.04" ]; then
       sudo apt-get install libsystemc-dev
     fi

docs/guide/install.rst

@@ -125,8 +125,8 @@ Those developing Verilator itself may also want these (see internals.rst):
 ::
 
    sudo apt-get install gdb graphviz cmake clang clang-format-14 gprof lcov
-   sudo apt-get install yapf3
-   sudo pip3 install sphinx sphinx_rtd_theme sphinxcontrib-spelling breathe
+   sudo apt-get install libclang-dev yapf3
+   sudo pip3 install clang sphinx sphinx_rtd_theme sphinxcontrib-spelling breathe
    cpan install Pod::Perldoc
    cpan install Parallel::Forker
 

include/verilatedos.h

@@ -57,16 +57,16 @@
 #  define VL_ATTR_WEAK __attribute__((weak))
 # endif
 # if defined(__clang__)
-#  define VL_ACQUIRE(...) __attribute__((acquire_capability(__VA_ARGS__)))
-#  define VL_ACQUIRE_SHARED(...) __attribute__((acquire_shared_capability(__VA_ARGS__)))
-#  define VL_RELEASE(...) __attribute__((release_capability(__VA_ARGS__)))
-#  define VL_RELEASE_SHARED(...) __attribute__((release_shared_capability(__VA_ARGS__)))
+#  define VL_ACQUIRE(...) __attribute__((annotate("ACQUIRE"))) __attribute__((acquire_capability(__VA_ARGS__)))
+#  define VL_ACQUIRE_SHARED(...) __attribute__((annotate("ACQUIRE_SHARED"))) __attribute__((acquire_shared_capability(__VA_ARGS__)))
+#  define VL_RELEASE(...) __attribute__((annotate("RELEASE"))) __attribute__((release_capability(__VA_ARGS__)))
+#  define VL_RELEASE_SHARED(...) __attribute__((annotate("RELEASE_SHARED"))) __attribute__((release_shared_capability(__VA_ARGS__)))
 #  define VL_TRY_ACQUIRE(...) __attribute__((try_acquire_capability(__VA_ARGS__)))
 #  define VL_TRY_ACQUIRE_SHARED(...) __attribute__((try_acquire_shared_capability(__VA_ARGS__)))
 #  define VL_CAPABILITY(x) __attribute__((capability(x)))
-#  define VL_REQUIRES(x) __attribute__((requires_capability(x)))
-#  define VL_GUARDED_BY(x) __attribute__((guarded_by(x)))
-#  define VL_EXCLUDES(x) __attribute__((locks_excluded(x)))
+#  define VL_REQUIRES(x) __attribute__((annotate("REQUIRES"))) __attribute__((requires_capability(x)))
+#  define VL_GUARDED_BY(x) __attribute__((annotate("GUARDED_BY"))) __attribute__((guarded_by(x)))
+#  define VL_EXCLUDES(x) __attribute__((annotate("EXCLUDES"))) __attribute__((locks_excluded(x)))
 #  define VL_SCOPED_CAPABILITY __attribute__((scoped_lockable))
 # endif
 # define VL_LIKELY(x) __builtin_expect(!!(x), 1)  // Prefer over C++20 [[likely]]

nodist/clang_check_attributes

@@ -0,0 +1,888 @@
+#!/usr/bin/env python3
+# pylint: disable=C0114,C0115,C0116,C0209,C0302,R0902,R0911,R0912,R0914,R0915,E1101
+#
+# Copyright 2022 by Wilson Snyder. Verilator is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU Lesser
+# General Public License Version 3 or the Apache License 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Apache-2.0
+
+import argparse
+import os
+import sys
+import shlex
+from typing import Callable, Iterable, Optional, Union
+import dataclasses
+from dataclasses import dataclass
+import enum
+from enum import Enum
+import multiprocessing
+import tempfile
+
+import clang.cindex
+from clang.cindex import CursorKind, Index, TranslationUnitSaveError, TranslationUnitLoadError
+
+
+def fully_qualified_name(node):
+    if node is None:
+        return []
+    if node.kind == CursorKind.TRANSLATION_UNIT:
+        return []
+    res = fully_qualified_name(node.semantic_parent)
+    if res:
+        return res + ([node.displayname] if node.displayname else [])
+    return [node.displayname] if node.displayname else []
+
+
+@dataclass
+class VlAnnotations:
+    mt_start: bool = False
+    mt_safe: bool = False
+    mt_safe_postinit: bool = False
+    mt_unsafe: bool = False
+    mt_unsafe_one: bool = False
+    pure: bool = False
+    guarded: bool = False
+    requires: bool = False
+    excludes: bool = False
+    acquire: bool = False
+    release: bool = False
+
+    def is_mt_safe_context(self):
+        return (not (self.mt_unsafe or self.mt_unsafe_one)
+                and (self.mt_safe or self.mt_start))
+
+    def is_pure_context(self):
+        return self.pure
+
+    def is_mt_unsafe_call(self):
+        return self.mt_unsafe or self.mt_unsafe_one
+
+    def is_mt_safe_call(self):
+        return (not self.is_mt_unsafe_call()
+                and (self.mt_safe or self.mt_safe_postinit or self.pure
+                     or self.requires or self.excludes or self.acquire
+                     or self.release))
+
+    def is_pure_call(self):
+        return self.pure
+
+    def __or__(self, other: "VlAnnotations"):
+        result = VlAnnotations()
+        for key, value in dataclasses.asdict(self).items():
+            setattr(result, key, value | getattr(other, key))
+        return result
+
+    def is_empty(self):
+        for value in dataclasses.asdict(self).values():
+            if value:
+                return False
+        return True
+
+    def __str__(self):
+        result = []
+        for field, value in dataclasses.asdict(self).items():
+            if value:
+                result.append(field)
+        return ", ".join(result)
+
+    @staticmethod
+    def from_nodes_list(nodes: Iterable):
+        result = VlAnnotations()
+        for node in nodes:
+            if node.kind == CursorKind.ANNOTATE_ATTR:
+                if node.displayname == "MT_START":
+                    result.mt_start = True
+                elif node.displayname == "MT_SAFE":
+                    result.mt_safe = True
+                elif node.displayname == "MT_SAFE_POSTINIT":
+                    result.mt_safe_postinit = True
+                elif node.displayname == "MT_UNSAFE":
+                    result.mt_unsafe = True
+                elif node.displayname == "MT_UNSAFE_ONE":
+                    result.mt_unsafe_one = True
+                elif node.displayname == "PURE":
+                    result.pure = True
+                elif node.displayname in ["ACQUIRE", "ACQUIRE_SHARED"]:
+                    result.acquire = True
+                elif node.displayname in ["RELEASE", "RELEASE_SHARED"]:
+                    result.release = True
+                elif node.displayname == "REQUIRES":
+                    result.requires = True
+                elif node.displayname in ["EXCLUDES", "MT_SAFE_EXCLUDES"]:
+                    result.excludes = True
+                elif node.displayname == "GUARDED_BY":
+                    result.guarded = True
+            # Attributes are always at the beginning
+            elif not node.kind.is_attribute():
+                break
+        return result
+
+
+class FunctionType(Enum):
+    UNKNOWN = enum.auto()
+    FUNCTION = enum.auto()
+    METHOD = enum.auto()
+    STATIC_METHOD = enum.auto()
+    CONSTRUCTOR = enum.auto()
+
+    @staticmethod
+    def from_node(node: clang.cindex.Cursor):
+        if node is None:
+            return FunctionType.UNKNOWN
+        if node.kind == CursorKind.FUNCTION_DECL:
+            return FunctionType.FUNCTION
+        if node.kind == CursorKind.CXX_METHOD and node.is_static_method():
+            return FunctionType.STATIC_METHOD
+        if node.kind == CursorKind.CXX_METHOD:
+            return FunctionType.METHOD
+        if node.kind == CursorKind.CONSTRUCTOR:
+            return FunctionType.CONSTRUCTOR
+        return FunctionType.UNKNOWN
+
+
+@dataclass(eq=False)
+class FunctionInfo:
+    name_parts: list[str]
+    usr: str
+    file: str
+    line: int
+    annotations: VlAnnotations
+    ftype: FunctionType
+
+    _hash: Optional[int] = dataclasses.field(default=None,
+                                             init=False,
+                                             repr=False)
+
+    @property
+    def name(self):
+        return "::".join(self.name_parts)
+
+    def __str__(self):
+        return f"[{self.name}@{self.file}:{self.line}]"
+
+    def __hash__(self):
+        if not self._hash:
+            self._hash = hash(f"{self.usr}:{self.file}:{self.line}")
+        return self._hash
+
+    def __eq__(self, other):
+        return (self.usr == other.usr and self.file == other.file
+                and self.line == other.line)
+
+    def copy(self, /, **changes):
+        return dataclasses.replace(self, **changes)
+
+    @staticmethod
+    def from_node(node: clang.cindex.Cursor,
+                  refd: Optional[clang.cindex.Cursor] = None,
+                  annotations: Optional[VlAnnotations] = None):
+        file = os.path.abspath(node.location.file.name)
+        line = node.location.line
+        if annotations is None:
+            annotations = VlAnnotations.from_nodes_list(node.get_children())
+        if refd is None:
+            refd = node.referenced
+        if refd is not None:
+            refd = refd.canonical
+        assert refd is not None
+        name_parts = fully_qualified_name(refd)
+        usr = refd.get_usr()
+        ftype = FunctionType.from_node(refd)
+
+        return FunctionInfo(name_parts, usr, file, line, annotations, ftype)
+
+
+class DiagnosticKind(Enum):
+    ANNOTATIONS_DEF_DECL_MISMATCH = enum.auto()
+    NON_PURE_CALL_IN_PURE_CTX = enum.auto()
+    NON_MT_SAFE_CALL_IN_MT_SAFE_CTX = enum.auto()
+
+    def __lt__(self, other):
+        return self.value < other.value
+
+
+@dataclass
+class Diagnostic:
+    target: FunctionInfo
+    source: FunctionInfo
+    source_ctx: FunctionInfo
+    kind: DiagnosticKind
+
+    _hash: Optional[int] = dataclasses.field(default=None,
+                                             init=False,
+                                             repr=False)
+
+    def __hash__(self):
+        if not self._hash:
+            self._hash = hash(
+                hash(self.target) ^ hash(self.source_ctx) ^ hash(self.kind))
+        return self._hash
+
+
+class CallAnnotationsValidator:
+
+    def __init__(self, diagnostic_cb: Callable[[Diagnostic], None],
+                 is_ignored_top_level: Callable[[clang.cindex.Cursor], bool],
+                 is_ignored_def: Callable[
+                     [clang.cindex.Cursor, clang.cindex.Cursor], bool],
+                 is_ignored_call: Callable[[clang.cindex.Cursor], bool]):
+        self._diagnostic_cb = diagnostic_cb
+        self._is_ignored_top_level = is_ignored_top_level
+        self._is_ignored_call = is_ignored_call
+        self._is_ignored_def = is_ignored_def
+
+        self._index = Index.create()
+
+        self._processed_headers: set[str] = set()
+
+        # Current context
+        self._call_location: Optional[FunctionInfo] = None
+        self._caller: Optional[FunctionInfo] = None
+        self._level: int = 0
+
+    def compile_and_analyze_file(self, source_file: str,
+                                 compiler_args: list[str],
+                                 build_dir: Optional[str]):
+        filename = os.path.abspath(source_file)
+        initial_cwd = "."
+
+        if build_dir:
+            initial_cwd = os.getcwd()
+            os.chdir(build_dir)
+        translation_unit = self._index.parse(filename, compiler_args)
+        has_errors = False
+        for diag in translation_unit.diagnostics:
+            if diag.severity > clang.cindex.Diagnostic.Error:
+                has_errors = True
+        if translation_unit and not has_errors:
+            self.process_translation_unit(translation_unit)
+        else:
+            print(f"%Error: parsing failed: {filename}", file=sys.stderr)
+        if build_dir:
+            os.chdir(initial_cwd)
+
+    def emit_diagnostic(self, target: Union[FunctionInfo, clang.cindex.Cursor],
+                        kind: DiagnosticKind):
+        assert self._caller is not None
+        assert self._call_location is not None
+        source = self._caller
+        source_ctx = self._call_location
+        if isinstance(target, FunctionInfo):
+            self._diagnostic_cb(Diagnostic(target, source, source_ctx, kind))
+        else:
+            self._diagnostic_cb(
+                Diagnostic(FunctionInfo.from_node(target), source, source_ctx,
+                           kind))
+
+    def iterate_children(self, children: Iterable[clang.cindex.Cursor],
+                         handler: Callable[[clang.cindex.Cursor], None]):
+        if children:
+            self._level += 1
+            for child in children:
+                handler(child)
+            self._level -= 1
+
+    def get_referenced_node_info(
+        self, node: clang.cindex.Cursor
+    ) -> tuple[bool, Optional[clang.cindex.Cursor], VlAnnotations,
+               Iterable[clang.cindex.Cursor]]:
+        if not node.spelling and not node.displayname:
+            return (False, None, VlAnnotations(), [])
+
+        refd = node.referenced
+        if refd is None:
+            raise ValueError("The node does not specify referenced node.")
+
+        refd = refd.canonical
+        children = list(refd.get_children())
+
+        annotations = VlAnnotations.from_nodes_list(children)
+        return (True, refd, annotations, children)
+
+    # Call handling
+
+    def process_method_call(self, node: clang.cindex.Cursor,
+                            refd: clang.cindex.Cursor,
+                            annotations: VlAnnotations):
+        assert self._call_location
+        ctx = self._call_location.annotations
+
+        # MT-safe context
+        if ctx.is_mt_safe_context():
+            is_mt_safe = False
+
+            if annotations.is_mt_safe_call():
+                is_mt_safe = True
+            elif not annotations.is_mt_unsafe_call():
+                # Check whether the object the method is called on is mt-safe
+                def find_object_ref(node):
+                    try:
+                        node = next(node.get_children())
+                        if node.kind != CursorKind.MEMBER_REF_EXPR:
+                            return None
+                        node = next(node.get_children())
+                        if node.kind == CursorKind.UNEXPOSED_EXPR:
+                            node = next(node.get_children())
+                        return node
+                    except StopIteration:
+                        return None
+
+                refn = find_object_ref(node)
+                # class/struct member
+                if refn and refn.kind == CursorKind.MEMBER_REF_EXPR and refn.referenced:
+                    refn = refn.referenced
+                    refna = VlAnnotations.from_nodes_list(refn.get_children())
+                    if refna.guarded:
+                        is_mt_safe = True
+                # variable
+                elif refn and refn.kind == CursorKind.DECL_REF_EXPR and refn.referenced:
+                    # This is probably a local or an argument. Assume it's safe.
+                    is_mt_safe = True
+
+            if not is_mt_safe:
+                self.emit_diagnostic(
+                    FunctionInfo.from_node(refd, refd, annotations),
+                    DiagnosticKind.NON_MT_SAFE_CALL_IN_MT_SAFE_CTX)
+
+        if ctx.is_pure_context():
+            if not annotations.is_pure_call():
+                self.emit_diagnostic(
+                    FunctionInfo.from_node(refd, refd, annotations),
+                    DiagnosticKind.NON_PURE_CALL_IN_PURE_CTX)
+
+    def process_function_call(self, refd: clang.cindex.Cursor,
+                              annotations: VlAnnotations):
+        assert self._call_location
+        ctx = self._call_location.annotations
+
+        # MT-safe context
+        if ctx.is_mt_safe_context():
+            if not annotations.is_mt_safe_call():
+                self.emit_diagnostic(
+                    FunctionInfo.from_node(refd, refd, annotations),
+                    DiagnosticKind.NON_MT_SAFE_CALL_IN_MT_SAFE_CTX)
+        # pure context
+        if ctx.is_pure_context():
+            if not annotations.is_pure_call():
+                self.emit_diagnostic(
+                    FunctionInfo.from_node(refd, refd, annotations),
+                    DiagnosticKind.NON_PURE_CALL_IN_PURE_CTX)
+
+    def process_constructor_call(self, refd: clang.cindex.Cursor,
+                                 annotations: VlAnnotations):
+        assert self._call_location
+        ctx = self._call_location.annotations
+
+        # Constructors are always OK in MT-safe context.
+
+        # pure context
+        if ctx.is_pure_context():
+            if not annotations.is_pure_call(
+            ) and not refd.is_default_constructor():
+                self.emit_diagnostic(
+                    FunctionInfo.from_node(refd, refd, annotations),
+                    DiagnosticKind.NON_PURE_CALL_IN_PURE_CTX)
+
+    def dispatch_call_node(self, node: clang.cindex.Cursor):
+        [supported, refd, annotations, _] = self.get_referenced_node_info(node)
+
+        if not supported:
+            self.iterate_children(node.get_children(),
+                                  self.dispatch_node_inside_definition)
+            return
+
+        assert refd is not None
+        if self._is_ignored_call(refd):
+            return
+
+        assert self._call_location is not None
+        node_file = os.path.abspath(node.location.file.name)
+        self._call_location = self._call_location.copy(file=node_file,
+                                                       line=node.location.line)
+
+        # Standalone functions and static class methods
+        if (refd.kind == CursorKind.FUNCTION_DECL
+                or refd.kind == CursorKind.CXX_METHOD
+                and refd.is_static_method()):
+            self.process_function_call(refd, annotations)
+            return
+        # Function pointer
+        if refd.kind in [
+                CursorKind.VAR_DECL, CursorKind.FIELD_DECL,
+                CursorKind.PARM_DECL
+        ]:
+            self.process_function_call(refd, annotations)
+            return
+        # Non-static class methods
+        if refd.kind == CursorKind.CXX_METHOD:
+            self.process_method_call(node, refd, annotations)
+            return
+        # Conversion method (e.g. `operator int()`)
+        if refd.kind == CursorKind.CONVERSION_FUNCTION:
+            self.process_method_call(node, refd, annotations)
+            return
+        # Constructors
+        if refd.kind == CursorKind.CONSTRUCTOR:
+            self.process_constructor_call(refd, annotations)
+            return
+
+        # Ignore other callables
+        print(f"{refd.location.file.name}:{refd.location.line}: "
+              f"{refd.displayname}    {refd.kind}\n"
+              f"    from: {node.location.file.name}:{node.location.line}")
+
+    # Definition handling
+
+    def dispatch_node_inside_definition(self, node: clang.cindex.Cursor):
+        if node.kind == CursorKind.CALL_EXPR:
+            self.dispatch_call_node(node)
+            return None
+
+        return self.iterate_children(node.get_children(),
+                                     self.dispatch_node_inside_definition)
+
+    def process_function_definition(self, node: clang.cindex.Cursor):
+        [supported, refd, annotations, _] = self.get_referenced_node_info(node)
+
+        if refd and self._is_ignored_def(node, refd):
+            return None
+
+        node_children = list(node.get_children())
+
+        if not supported:
+            return self.iterate_children(node_children, self.dispatch_node)
+
+        assert refd is not None
+
+        prev_caller = self._caller
+        prev_call_location = self._call_location
+
+        def_annotations = VlAnnotations.from_nodes_list(node_children)
+
+        if not (def_annotations.is_empty() or def_annotations == annotations):
+            # Use definition's annotations for the diagnostic
+            # source (i.e. the definition)
+            self._caller = FunctionInfo.from_node(node, refd, def_annotations)
+            self._call_location = self._caller
+
+            self.emit_diagnostic(
+                FunctionInfo.from_node(refd, refd, annotations),
+                DiagnosticKind.ANNOTATIONS_DEF_DECL_MISMATCH)
+
+        # Use concatenation of definition and declaration annotations
+        # for callees validation.
+        self._caller = FunctionInfo.from_node(node, refd,
+                                              def_annotations | annotations)
+        self._call_location = self._caller
+
+        self.iterate_children(node_children,
+                              self.dispatch_node_inside_definition)
+
+        self._call_location = prev_call_location
+        self._caller = prev_caller
+
+        return None
+
+    # Nodes not located inside definition
+
+    def dispatch_node(self, node: clang.cindex.Cursor):
+        if node.is_definition() and node.kind in [
+                CursorKind.CXX_METHOD, CursorKind.FUNCTION_DECL,
+                CursorKind.CONSTRUCTOR, CursorKind.CONVERSION_FUNCTION
+        ]:
+            return self.process_function_definition(node)
+        if node.is_definition() and node.kind in [
+                CursorKind.NAMESPACE, CursorKind.STRUCT_DECL,
+                CursorKind.UNION_DECL, CursorKind.CLASS_DECL
+        ]:
+            return self.iterate_children(node.get_children(),
+                                         self.dispatch_node)
+
+        return self.iterate_children(node.get_children(), self.dispatch_node)
+
+    def process_translation_unit(
+            self, translation_unit: clang.cindex.TranslationUnit):
+        self._level += 1
+        for child in translation_unit.cursor.get_children():
+            if self._is_ignored_top_level(child):
+                continue
+            if self._processed_headers:
+                filename = os.path.abspath(child.location.file.name)
+                if filename in self._processed_headers:
+                    continue
+            self.dispatch_node(child)
+        self._level -= 1
+
+        self._processed_headers.update([
+            os.path.abspath(str(hdr.source))
+            for hdr in translation_unit.get_includes()
+        ])
+
+
+@dataclass
+class CompileCommand:
+    refid: int
+    filename: str
+    args: list[str]
+    directory: str = dataclasses.field(default_factory=os.getcwd)
+
+
+def get_filter_funcs(verilator_root: str):
+    verilator_root = os.path.abspath(verilator_root) + "/"
+
+    def is_ignored_top_level(node: clang.cindex.Cursor) -> bool:
+        # Anything defined in a header outside Verilator root
+        if not node.location.file:
+            return True
+        filename = os.path.abspath(node.location.file.name)
+        return not filename.startswith(verilator_root)
+
+    def is_ignored_def(node: clang.cindex.Cursor,
+                       refd: clang.cindex.Cursor) -> bool:
+        # __*
+        if str(refd.spelling).startswith("__"):
+            return True
+
+        # Anything defined in a header outside Verilator root
+        if not node.location.file:
+            return True
+        filename = os.path.abspath(node.location.file.name)
+        if not filename.startswith(verilator_root):
+            return True
+
+        return False
+
+    def is_ignored_call(refd: clang.cindex.Cursor) -> bool:
+        # __*
+        if str(refd.spelling).startswith("__"):
+            return True
+
+        # std::*
+        fqn = fully_qualified_name(refd)
+        if fqn and fqn[0] == "std":
+            return True
+
+        # Anything declared in a header outside Verilator root
+        if not refd.location.file:
+            return True
+        filename = os.path.abspath(refd.location.file.name)
+        if not filename.startswith(verilator_root):
+            return True
+
+        return False
+
+    return (is_ignored_top_level, is_ignored_def, is_ignored_call)
+
+
+def precompile_header(compile_command: CompileCommand, tmp_dir: str) -> str:
+    try:
+        initial_cwd = os.getcwd()
+        os.chdir(compile_command.directory)
+
+        index = Index.create()
+        translation_unit = index.parse(compile_command.filename,
+                                       compile_command.args)
+        for diag in translation_unit.diagnostics:
+            if diag.severity > clang.cindex.Diagnostic.Error:
+                pch_file = None
+                break
+        else:
+            pch_file = os.path.join(
+                tmp_dir,
+                f"{compile_command.refid:02}_{os.path.basename(compile_command.filename)}.pch"
+            )
+            translation_unit.save(pch_file)
+
+        os.chdir(initial_cwd)
+
+        if pch_file:
+            return pch_file
+
+    except (TranslationUnitSaveError, TranslationUnitLoadError, OSError):
+        pass
+
+    print(
+        f"%Warning: Precompiling failed, skipping: {compile_command.filename}")
+    return ""
+
+
+# Compile and analyze inputs in a single process.
+def run_analysis(ccl: Iterable[CompileCommand], pccl: Iterable[CompileCommand],
+                 diagnostic_cb: Callable[[Diagnostic],
+                                         None], verilator_root: str):
+    (is_ignored_top_level, is_ignored_def,
+     is_ignored_call) = get_filter_funcs(verilator_root)
+
+    prefix = "verilator_clang_check_attributes_"
+    with tempfile.TemporaryDirectory(prefix=prefix) as tmp_dir:
+        extra_args = []
+        for pcc in pccl:
+            pch_file = precompile_header(pcc, tmp_dir)
+            if pch_file:
+                extra_args += ["-include-pch", pch_file]
+
+        cav = CallAnnotationsValidator(diagnostic_cb, is_ignored_top_level,
+                                       is_ignored_def, is_ignored_call)
+        for compile_command in ccl:
+            cav.compile_and_analyze_file(compile_command.filename,
+                                         compile_command.args + extra_args,
+                                         compile_command.directory)
+
+
+class ParallelAnalysisProcess:
+    cav: Optional[CallAnnotationsValidator] = None
+    diags: set[Diagnostic] = dataclasses.field(default_factory=set)
+    tmp_dir: str = ""
+
+    @staticmethod
+    def init_data(verilator_root: str, tmp_dir: str):
+        (is_ignored_top_level, is_ignored_def,
+         is_ignored_call) = get_filter_funcs(verilator_root)
+
+        ParallelAnalysisProcess.cav = CallAnnotationsValidator(
+            ParallelAnalysisProcess._diagnostic_handler, is_ignored_top_level,
+            is_ignored_def, is_ignored_call)
+        ParallelAnalysisProcess.tmp_dir = tmp_dir
+
+    @staticmethod
+    def _diagnostic_handler(diag: Diagnostic):
+        ParallelAnalysisProcess.diags.add(diag)
+
+    @staticmethod
+    def analyze_cpp_file(compile_command: CompileCommand) -> set[Diagnostic]:
+        ParallelAnalysisProcess.diags = set()
+        assert ParallelAnalysisProcess.cav is not None
+        ParallelAnalysisProcess.cav.compile_and_analyze_file(
+            compile_command.filename, compile_command.args,
+            compile_command.directory)
+        return ParallelAnalysisProcess.diags
+
+    @staticmethod
+    def precompile_header(compile_command: CompileCommand) -> str:
+        return precompile_header(compile_command,
+                                 ParallelAnalysisProcess.tmp_dir)
+
+
+# Compile and analyze inputs in multiple processes.
+def run_parallel_analysis(ccl: Iterable[CompileCommand],
+                          pccl: Iterable[CompileCommand],
+                          diagnostic_cb: Callable[[Diagnostic], None],
+                          jobs_count: int, verilator_root: str):
+    prefix = "verilator_clang_check_attributes_"
+    with tempfile.TemporaryDirectory(prefix=prefix) as tmp_dir:
+        with multiprocessing.Pool(
+                processes=jobs_count,
+                initializer=ParallelAnalysisProcess.init_data,
+                initargs=[verilator_root, tmp_dir]) as pool:
+            extra_args = []
+            for pch_file in pool.imap_unordered(
+                    ParallelAnalysisProcess.precompile_header, pccl):
+                if pch_file:
+                    extra_args += ["-include-pch", pch_file]
+
+            if extra_args:
+                for compile_command in ccl:
+                    compile_command.args = compile_command.args + extra_args
+
+            for diags in pool.imap_unordered(
+                    ParallelAnalysisProcess.analyze_cpp_file, ccl, 1):
+                for diag in diags:
+                    diagnostic_cb(diag)
+
+
+class TopDownSummaryPrinter():
+
+    @dataclass
+    class FunctionCallees:
+        info: FunctionInfo
+        calees: set[FunctionInfo]
+        mismatch: Optional[FunctionInfo] = None
+        non_mt_safe_call_in_mt_safe: Optional[FunctionInfo] = None
+        non_pure_call_in_pure: Optional[FunctionInfo] = None
+
+    def __init__(self):
+        self._is_first_group = True
+
+        self._funcs: dict[str, TopDownSummaryPrinter.FunctionCallees] = {}
+        self._unsafe_in_safe: set[str] = set()
+
+    def begin_group(self, label):
+        if not self._is_first_group:
+            print()
+
+        print(f"%Error: {label}")
+
+        self._is_first_group = False
+
+    def handle_diagnostic(self, diag: Diagnostic):
+        usr = diag.source.usr
+        func = self._funcs.get(usr, None)
+        if func is None:
+            func = TopDownSummaryPrinter.FunctionCallees(diag.source, set())
+            self._funcs[usr] = func
+        if diag.kind == DiagnosticKind.ANNOTATIONS_DEF_DECL_MISMATCH:
+            func.mismatch = diag.target
+        else:
+            func.calees.add(diag.target)
+            self._unsafe_in_safe.add(diag.target.usr)
+            if diag.kind == DiagnosticKind.NON_MT_SAFE_CALL_IN_MT_SAFE_CTX:
+                func.non_mt_safe_call_in_mt_safe = diag.target
+            elif diag.kind == DiagnosticKind.NON_PURE_CALL_IN_PURE_CTX:
+                func.non_pure_call_in_pure = diag.target
+
+    def print_summary(self, root_dir: str):
+        row_groups: dict[str, list[list[str]]] = {}
+        column_widths = [0, 0]
+        for func in sorted(self._funcs.values(),
+                           key=lambda func:
+                           (func.info.file, func.info.line, func.info.usr)):
+            func_info = func.info
+            relfile = os.path.relpath(func_info.file, root_dir)
+
+            row_group = []
+            name = f"\"{func_info.name}\" "
+            if func.mismatch:
+                name += "declaration does not match definition"
+            elif func.non_mt_safe_call_in_mt_safe:
+                name += "is mtsafe but calls non-mtsafe function(s)"
+            elif func.non_pure_call_in_pure:
+                name += "is pure but calls non-pure function(s)"
+            else:
+                name += "for unknown reason (please add description)"
+
+            if func.mismatch:
+                mrelfile = os.path.relpath(func.mismatch.file, root_dir)
+                row_group.append([
+                    f"{mrelfile}:{func.mismatch.line}:",
+                    f"[{func.mismatch.annotations}]",
+                    func.mismatch.name + " [declaration]"
+                ])
+
+            row_group.append([
+                f"{relfile}:{func_info.line}:", f"[{func_info.annotations}]",
+                func_info.name
+            ])
+
+            for callee in sorted(func.calees,
+                                 key=lambda func:
+                                 (func.file, func.line, func.usr)):
+                crelfile = os.path.relpath(callee.file, root_dir)
+                row_group.append([
+                    f"{crelfile}:{callee.line}:", f"[{callee.annotations}]",
+                    "  " + callee.name
+                ])
+
+            row_groups[name] = row_group
+
+            for row in row_group:
+                for row_id, value in enumerate(row[0:-1]):
+                    column_widths[row_id] = max(column_widths[row_id],
+                                                len(value))
+
+        for label, rows in sorted(row_groups.items(), key=lambda kv: kv[0]):
+            self.begin_group(label)
+            for row in rows:
+                print(f"{row[0]:<{column_widths[0]}}  "
+                      f"{row[1]:<{column_widths[1]}}    "
+                      f"{row[2]}")
+        print(
+            f"Number of functions reported unsafe: {len(self._unsafe_in_safe)}"
+        )
+
+
+def main():
+    default_verilator_root = os.path.abspath(
+        os.path.join(os.path.dirname(__file__), ".."))
+
+    parser = argparse.ArgumentParser(
+        allow_abbrev=False,
+        formatter_class=argparse.RawDescriptionHelpFormatter,
+        description="""Check function annotations for correctness""",
+        epilog=
+        """Copyright 2022 by Wilson Snyder. Verilator is free software; you
+    can redistribute it and/or modify it under the terms of either the GNU
+    Lesser General Public License Version 3 or the Apache License 2.0.
+    SPDX-License-Identifier: LGPL-3.0-only OR Apache-2.0""")
+
+    parser.add_argument("--verilator-root",
+                        type=str,
+                        default=default_verilator_root,
+                        help="Path to Verilator sources root directory.")
+    parser.add_argument("--jobs",
+                        "-j",
+                        type=int,
+                        default=0,
+                        help="Number of parallel jobs to use.")
+    parser.add_argument("--cxxflags",
+                        type=str,
+                        default=None,
+                        help="Flags passed to clang++.")
+    parser.add_argument(
+        "--compilation-root",
+        type=str,
+        default=os.getcwd(),
+        help="Directory used as CWD when compiling source files.")
+    parser.add_argument(
+        "-c",
+        "--precompile",
+        action="append",
+        help="Header file to be precompiled and cached at the start.")
+    parser.add_argument("file",
+                        type=str,
+                        nargs="+",
+                        help="Source file to analyze.")
+
+    cmdline = parser.parse_args()
+
+    if cmdline.jobs == 0:
+        cmdline.jobs = max(1, len(os.sched_getaffinity(0)))
+
+    if not cmdline.compilation_root:
+        cmdline.compilation_root = cmdline.verilator_root
+
+    verilator_root = os.path.abspath(cmdline.verilator_root)
+    compilation_root = os.path.abspath(cmdline.compilation_root)
+
+    default_cxx_flags = [
+        f"-I{verilator_root}/src",
+        f"-I{verilator_root}/include",
+        f"-I{verilator_root}/src/obj_opt",
+        "-fcoroutines-ts",
+    ]
+    if cmdline.cxxflags is not None:
+        cxxflags = shlex.split(cmdline.cxxflags)
+    else:
+        cxxflags = default_cxx_flags
+
+    precompile_commands_list = []
+
+    if cmdline.precompile:
+        hdr_cxxflags = ['-xc++-header'] + cxxflags
+        for refid, file in enumerate(cmdline.precompile):
+            filename = os.path.abspath(file)
+            compile_command = CompileCommand(refid, filename, hdr_cxxflags,
+                                             compilation_root)
+            precompile_commands_list.append(compile_command)
+
+    compile_commands_list = []
+    for refid, file in enumerate(cmdline.file):
+        filename = os.path.abspath(file)
+        compile_command = CompileCommand(refid, filename, cxxflags,
+                                         compilation_root)
+        compile_commands_list.append(compile_command)
+
+    summary_printer = TopDownSummaryPrinter()
+
+    if cmdline.jobs == 1:
+        run_analysis(compile_commands_list, precompile_commands_list,
+                     summary_printer.handle_diagnostic, verilator_root)
+    else:
+        run_parallel_analysis(compile_commands_list, precompile_commands_list,
+                              summary_printer.handle_diagnostic, cmdline.jobs,
+                              verilator_root)
+
+    summary_printer.print_summary(verilator_root)
+
+
+if __name__ == '__main__':
+    main()

test_regress/t/t_a5_attributes_include.pl

@@ -0,0 +1,44 @@
+#!/usr/bin/env perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2022 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+scenarios(dist => 1);
+rerunnable(0);
+if ($ENV{VERILATOR_TEST_NO_ATTRIBUTES}) {
+    skip("Skipping due to VERILATOR_TEST_NO_ATTRIBUTES");
+} else {
+    check();
+}
+sub check {
+    my $root = "..";
+    # some of the files are only used in verilation
+    # and are only in "include" folder
+    my @srcfiles = glob("$root/include/*.cpp");
+    my $srcfiles_str = join(" ", @srcfiles);
+    my $clang_args = "-I$root/include/ -I$root/include/vltstd/ -fcoroutines-ts";
+
+    sub run_clang_check {
+        {
+            my $cmd = qq{python3 -c "from clang.cindex import Index; index = Index.create(); print(\\"Clang imported\\")";};
+            print "\t$cmd\n" if $::Debug;
+            my $out = `$cmd`;
+            if (!$out || $out !~ /Clang imported/) { skip("No libclang installed\n"); return 1; }
+        }
+        run(logfile => $Self->{run_log_filename},
+            tee => 1,
+            cmd => ["python3", "$root/nodist/clang_check_attributes --verilator-root=$root --cxxflags='$clang_args' $srcfiles_str"]);
+
+        file_grep($Self->{run_log_filename}, "Number of functions reported unsafe: 0");
+    }
+
+    run_clang_check();
+}
+
+ok(1);
+1;

test_regress/t/t_a5_attributes_src.pl

@@ -0,0 +1,46 @@
+#!/usr/bin/env perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2022 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+scenarios(dist => 1);
+rerunnable(0);
+if ($ENV{VERILATOR_TEST_NO_ATTRIBUTES}) {
+    skip("Skipping due to VERILATOR_TEST_NO_ATTRIBUTES");
+} else {
+    check();
+}
+sub check {
+    my $root = "..";
+    # some of the files are only used in verilation
+    # and are only in "include" folder
+    my @srcfiles = grep { !/\/(V3Const|Vlc\w*|\w*_test|\w*_sc|\w*.yy).cpp$/ }
+                   glob("$root/src/*.cpp $root/src/obj_opt/V3Const__gen.cpp");
+    my $srcfiles_str = join(" ", @srcfiles);
+    my $precompile_args = "-c $root/src/V3Ast.h";
+    my $clang_args = "-I$root/src/ -I$root/include/ -I$root/src/obj_opt/ -fcoroutines-ts";
+
+    sub run_clang_check {
+        {
+            my $cmd = qq{python3 -c "from clang.cindex import Index; index = Index.create(); print(\\"Clang imported\\")";};
+            print "\t$cmd\n" if $::Debug;
+            my $out = `$cmd`;
+            if (!$out || $out !~ /Clang imported/) { skip("No libclang installed\n"); return 1; }
+        }
+        run(logfile => $Self->{run_log_filename},
+            tee => 1,
+            cmd => ["python3", "$root/nodist/clang_check_attributes --verilator-root=$root --cxxflags='$clang_args' $precompile_args $srcfiles_str"]);
+
+        file_grep($Self->{run_log_filename}, "Number of functions reported unsafe: 24");
+    }
+
+    run_clang_check();
+}
+
+ok(1);
+1;

test_regress/t/t_dist_attributes_bad.cpp

@@ -0,0 +1,169 @@
+#include "verilatedos.h"
+
+#include "t_dist_attributes_bad.h"
+
+// Non-Static Functions, Annotated declaration, Unannotated definition.
+// (definitions)
+EMIT_ALL(SIG_UNANNOTATED, nsf_au, /**/, {})
+
+// Non-Static Functions, Unannotated declaration, Annotated definition.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, nsf_ua, /**/, {})
+
+// Non-Static Functions, Annotated declaration, Annotated definition.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, nsf_aa, /**/, {})
+
+// Non-Static Functions, Annotated declaration, Annotated definition.
+// Definitions have extra annotations.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, nsf_ae, /**/, VL_PURE VL_MT_SAFE{})
+
+// Non-Static Functions, Annotated declaration, Annotated definition.
+// Declarations have extra annotations.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, nsf_ea, /**/, {})
+
+// Non-Static Functions (call test).
+EMIT_ALL(VL_ATTR_UNUSED static SIG_ANNOTATED, nsf_test_caller_func, /**/, {
+    VerilatedMutex m;
+
+    EMIT_ALL(CALL, nsf_au, m, ;)
+    EMIT_ALL(CALL, nsf_ua, m, ;)
+    EMIT_ALL(CALL, nsf_aa, m, ;)
+    EMIT_ALL(CALL, nsf_ae, m, ;)
+    EMIT_ALL(CALL, nsf_ea, m, ;)
+})
+
+// Inline Functions in Header (call test).
+EMIT_ALL(VL_ATTR_UNUSED static SIG_ANNOTATED, ifh_test_caller_func, /**/, {
+    VerilatedMutex m;
+
+    EMIT_ALL(CALL, ifh, m, ;)
+})
+
+// Static Functions in Cpp file.
+EMIT_ALL(inline SIG_ANNOTATED, sfc, /**/, {})
+
+// Static Functions in Cpp file (call test).
+EMIT_ALL(VL_ATTR_UNUSED static SIG_ANNOTATED, sfc_test_caller_func, /**/, {
+    VerilatedMutex m;
+
+    EMIT_ALL(CALL, sfc, m, ;)
+})
+
+// Static Class Methods, Annotated declaration, Unannotated definition.
+// (definitions)
+EMIT_ALL(SIG_UNANNOTATED, TestClass::scm_au, /**/, {})
+
+// Static Class Methods, Unannotated declaration, Annotated definition.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, TestClass::scm_ua, /**/, {})
+
+// Static Class Methods, Annotated declaration, Annotated definition.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, TestClass::scm_aa, /**/, {})
+
+// Static Class Methods, Annotated declaration, Annotated definition.
+// Definitions have extra annotations.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, TestClass::scm_ae, /**/, VL_PURE VL_MT_SAFE{})
+
+// Static Class Methods, Annotated declaration, Annotated definition.
+// Declarations have extra annotations.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, TestClass::scm_ea, /**/, {})
+
+// Static Class Methods (call test).
+// (definition)
+EMIT_ALL(SIG_ANNOTATED, TestClass::scm_test_caller_smethod, /**/, {
+    VerilatedMutex m;
+
+    EMIT_ALL(CALL, TestClass::scm_au, m, ;)
+    EMIT_ALL(CALL, TestClass::scm_ua, m, ;)
+    EMIT_ALL(CALL, TestClass::scm_aa, m, ;)
+    EMIT_ALL(CALL, TestClass::scm_ae, m, ;)
+    EMIT_ALL(CALL, TestClass::scm_ea, m, ;)
+
+    TestClass tc;
+    EMIT_ALL(CALL, tc.scm_au, m, ;)
+    EMIT_ALL(CALL, tc.scm_ua, m, ;)
+    EMIT_ALL(CALL, tc.scm_aa, m, ;)
+    EMIT_ALL(CALL, tc.scm_ae, m, ;)
+    EMIT_ALL(CALL, tc.scm_ea, m, ;)
+
+    TestClass* tcp = &tc;
+    EMIT_ALL(CALL, tcp->scm_au, m, ;)
+    EMIT_ALL(CALL, tcp->scm_ua, m, ;)
+    EMIT_ALL(CALL, tcp->scm_aa, m, ;)
+    EMIT_ALL(CALL, tcp->scm_ae, m, ;)
+    EMIT_ALL(CALL, tcp->scm_ea, m, ;)
+})
+
+// Inline Static Class Methods (call test).
+// (definition)
+EMIT_ALL(SIG_ANNOTATED, TestClass::iscm_test_caller_smethod, /**/, {
+    VerilatedMutex m;
+
+    EMIT_ALL(CALL, TestClass::iscm, m, ;)
+
+    TestClass tc;
+    EMIT_ALL(CALL, tc.iscm, m, ;)
+
+    TestClass* tcp = &tc;
+    EMIT_ALL(CALL, tcp->iscm, m, ;)
+})
+
+// Class Methods, Annotated declaration, Unannotated definition.
+// (definitions)
+EMIT_ALL(SIG_UNANNOTATED, TestClass::cm_au, /**/, {})
+
+// Class Methods, Unannotated declaration, Annotated definition.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, TestClass::cm_ua, /**/, {})
+
+// Class Methods, Annotated declaration, Annotated definition.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, TestClass::cm_aa, /**/, {})
+
+// Class Methods, Annotated declaration, Annotated definition.
+// Definitions have extra annotations.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, TestClass::cm_ae, /**/, VL_PURE VL_MT_SAFE{})
+
+// Class Methods, Annotated declaration, Annotated definition.
+// Declarations have extra annotations.
+// (definitions)
+EMIT_ALL(SIG_ANNOTATED, TestClass::cm_ea, /**/, {})
+
+// Class Methods (call test).
+// (definition)
+EMIT_ALL(SIG_ANNOTATED, TestClass::cm_test_caller_smethod, /**/, {
+    VerilatedMutex m;
+
+    TestClass tc;
+    EMIT_ALL(CALL, tc.cm_au, m, ;)
+    EMIT_ALL(CALL, tc.cm_ua, m, ;)
+    EMIT_ALL(CALL, tc.cm_aa, m, ;)
+    EMIT_ALL(CALL, tc.cm_ae, m, ;)
+    EMIT_ALL(CALL, tc.cm_ea, m, ;)
+
+    TestClass* tcp = &tc;
+    EMIT_ALL(CALL, tcp->cm_au, m, ;)
+    EMIT_ALL(CALL, tcp->cm_ua, m, ;)
+    EMIT_ALL(CALL, tcp->cm_aa, m, ;)
+    EMIT_ALL(CALL, tcp->cm_ae, m, ;)
+    EMIT_ALL(CALL, tcp->cm_ea, m, ;)
+})
+
+// Inline Class Methods (call test).
+// (definition)
+EMIT_ALL(SIG_ANNOTATED, TestClass::icm_test_caller_smethod, /**/, {
+    VerilatedMutex m;
+
+    TestClass tc;
+    EMIT_ALL(CALL, tc.icm, m, ;)
+
+    TestClass* tcp = &tc;
+    EMIT_ALL(CALL, tcp->icm, m, ;)
+})

test_regress/t/t_dist_attributes_bad.h

@@ -0,0 +1,256 @@
+#ifndef T_DIST_ATTRIBUTES_BAD_H_
+#define T_DIST_ATTRIBUTES_BAD_H_
+
+#include "verilatedos.h"
+
+#include "verilated.h"
+
+#include <mutex>
+
+#define NO_ANNOTATION
+
+#define CALL_0(prefix, annotation, aarg_type, aarg, val) prefix##_##annotation(val)
+
+#define CALL_1(prefix, annotation, aarg_type, aarg, val) prefix##_##annotation(val)
+
+#define SIG_ANNOTATED_0(prefix, annotation, aarg_type, aarg, val) \
+    void prefix##_##annotation(aarg_type aarg) annotation
+
+#define SIG_ANNOTATED_1(prefix, annotation, aarg_type, aarg, val) \
+    void prefix##_##annotation(aarg_type aarg) annotation(aarg)
+
+#define SIG_UNANNOTATED_0(prefix, annotation, aarg_type, aarg, val) \
+    void prefix##_##annotation(aarg_type aarg)
+
+#define SIG_UNANNOTATED_1(prefix, annotation, aarg_type, aarg, val) \
+    void prefix##_##annotation(aarg_type aarg)
+
+// clang-format off
+#define EMIT_ALL(before, sig_prefix, val, after) \
+    before##_0(sig_prefix, NO_ANNOTATION,       VerilatedMutex&, mtx, val) after \
+    before##_0(sig_prefix, VL_PURE,             VerilatedMutex&, mtx, val) after \
+    before##_0(sig_prefix, VL_MT_SAFE,          VerilatedMutex&, mtx, val) after \
+    before##_0(sig_prefix, VL_MT_SAFE_POSTINIT, VerilatedMutex&, mtx, val) after \
+    before##_0(sig_prefix, VL_MT_UNSAFE,        VerilatedMutex&, mtx, val) after \
+    before##_0(sig_prefix, VL_MT_UNSAFE_ONE,    VerilatedMutex&, mtx, val) after \
+    before##_0(sig_prefix, VL_MT_START,         VerilatedMutex&, mtx, val) after \
+    before##_1(sig_prefix, VL_ACQUIRE,          VerilatedMutex&, mtx, val) after \
+    before##_1(sig_prefix, VL_REQUIRES,         VerilatedMutex&, mtx, val) after \
+    before##_1(sig_prefix, VL_RELEASE,          VerilatedMutex&, mtx, val) after \
+    before##_1(sig_prefix, VL_ACQUIRE_SHARED,   VerilatedMutex&, mtx, val) after \
+    before##_1(sig_prefix, VL_RELEASE_SHARED,   VerilatedMutex&, mtx, val) after \
+    before##_1(sig_prefix, VL_EXCLUDES,         VerilatedMutex&, mtx, val) after \
+    before##_1(sig_prefix, VL_MT_SAFE_EXCLUDES, VerilatedMutex&, mtx, val) after
+// clang-format on
+
+// Non-Static Functions, Annotated declaration, Unannotated definition.
+// (declarations)
+EMIT_ALL(SIG_ANNOTATED, nsf_au, /**/, ;)
+
+// Non-Static Functions, Unannotated declaration, Annotated definition.
+// (declarations)
+EMIT_ALL(SIG_UNANNOTATED, nsf_ua, /**/, ;)
+
+// Non-Static Functions, Annotated declaration, Annotated definition.
+// (declarations)
+EMIT_ALL(SIG_ANNOTATED, nsf_aa, /**/, ;)
+
+// Non-Static Functions, Annotated declaration, Annotated definition.
+// Definitions have extra annotations.
+// (declarations)
+EMIT_ALL(SIG_ANNOTATED, nsf_ae, /**/, ;)
+
+// Non-Static Functions, Annotated declaration, Annotated definition.
+// Declarations have extra annotations.
+// (declarations)
+EMIT_ALL(SIG_ANNOTATED, nsf_ea, /**/, VL_PURE VL_MT_SAFE;)
+
+// Non-Static Functions (call test in header).
+EMIT_ALL(inline SIG_ANNOTATED, nsf_test_caller_func_hdr, /**/, {
+    VerilatedMutex m;
+
+    EMIT_ALL(CALL, nsf_au, m, ;)
+    EMIT_ALL(CALL, nsf_ua, m, ;)
+    EMIT_ALL(CALL, nsf_aa, m, ;)
+    EMIT_ALL(CALL, nsf_ae, m, ;)
+    EMIT_ALL(CALL, nsf_ea, m, ;)
+})
+
+// Inline Functions in Header.
+EMIT_ALL(inline SIG_ANNOTATED, ifh, /**/, {})
+
+// Inline Functions in Header (call test in header).
+EMIT_ALL(inline SIG_ANNOTATED, ifh_test_caller_func_hdr, /**/, {
+    VerilatedMutex m;
+
+    EMIT_ALL(CALL, ifh, m, ;)
+})
+
+struct GuardMe {
+    void safe_if_guarded_or_local() {}
+
+    operator int() const { return 4; }
+};
+
+class TestClass {
+    VerilatedMutex m_mtx;
+    GuardMe m_guardme VL_GUARDED_BY(m_mtx);
+
+    GuardMe m_guardme_unguarded;
+
+public:
+    // Static Class Methods, Annotated declaration, Unannotated definition.
+    // (declarations)
+    EMIT_ALL(static SIG_ANNOTATED, scm_au, /**/, ;)
+
+    // Static Class Methods, Unannotated declaration, Annotated definition.
+    // (declarations)
+    EMIT_ALL(static SIG_UNANNOTATED, scm_ua, /**/, ;)
+
+    // Static Class Methods, Annotated declaration, Annotated definition.
+    // (declarations)
+    EMIT_ALL(static SIG_ANNOTATED, scm_aa, /**/, ;)
+
+    // Static Class Methods, Annotated declaration, Annotated definition.
+    // Definitions have extra annotations.
+    // (declarations)
+    EMIT_ALL(static SIG_ANNOTATED, scm_ae, /**/, ;)
+
+    // Static Class Methods, Annotated declaration, Annotated definition.
+    // Declarations have extra annotations.
+    // (declarations)
+    EMIT_ALL(static SIG_ANNOTATED, scm_ea, /**/, VL_PURE VL_MT_SAFE;)
+
+    // Static Class Methods (call test in header).
+    EMIT_ALL(static SIG_ANNOTATED, scm_test_caller_smethod_hdr, /**/, {
+        VerilatedMutex m;
+
+        EMIT_ALL(CALL, TestClass::scm_au, m, ;)
+        EMIT_ALL(CALL, TestClass::scm_ua, m, ;)
+        EMIT_ALL(CALL, TestClass::scm_aa, m, ;)
+        EMIT_ALL(CALL, TestClass::scm_ae, m, ;)
+        EMIT_ALL(CALL, TestClass::scm_ea, m, ;)
+
+        TestClass tc;
+        EMIT_ALL(CALL, tc.scm_au, m, ;)
+        EMIT_ALL(CALL, tc.scm_ua, m, ;)
+        EMIT_ALL(CALL, tc.scm_aa, m, ;)
+        EMIT_ALL(CALL, tc.scm_ae, m, ;)
+        EMIT_ALL(CALL, tc.scm_ea, m, ;)
+
+        TestClass* tcp = &tc;
+        EMIT_ALL(CALL, tcp->scm_au, m, ;)
+        EMIT_ALL(CALL, tcp->scm_ua, m, ;)
+        EMIT_ALL(CALL, tcp->scm_aa, m, ;)
+        EMIT_ALL(CALL, tcp->scm_ae, m, ;)
+        EMIT_ALL(CALL, tcp->scm_ea, m, ;)
+    })
+
+    // Static Class Methods (call test).
+    // (declaration)
+    EMIT_ALL(static SIG_ANNOTATED, scm_test_caller_smethod, /**/, ;)
+
+    // Inline Static Class Methods.
+    EMIT_ALL(static SIG_ANNOTATED, iscm, /**/, {})
+
+    // Inline Static Class Methods (call test in header).
+    EMIT_ALL(static SIG_ANNOTATED, iscm_test_caller_smethod_hdr, /**/, {
+        VerilatedMutex m;
+
+        EMIT_ALL(CALL, TestClass::iscm, m, ;)
+
+        TestClass tc;
+        EMIT_ALL(CALL, tc.iscm, m, ;)
+
+        TestClass* tcp = &tc;
+        EMIT_ALL(CALL, tcp->iscm, m, ;)
+    })
+
+    // Inline Static Class Methods (call test).
+    // (declaration)
+    EMIT_ALL(static SIG_ANNOTATED, iscm_test_caller_smethod, /**/, ;)
+
+    // Class Methods, Annotated declaration, Unannotated definition.
+    // (declarations)
+    EMIT_ALL(SIG_ANNOTATED, cm_au, /**/, ;)
+
+    // Class Methods, Unannotated declaration, Annotated definition.
+    // (declarations)
+    EMIT_ALL(SIG_UNANNOTATED, cm_ua, /**/, ;)
+
+    // Class Methods, Annotated declaration, Annotated definition.
+    // (declarations)
+    EMIT_ALL(SIG_ANNOTATED, cm_aa, /**/, ;)
+
+    // Class Methods, Annotated declaration, Annotated definition.
+    // Definitions have extra annotations.
+    // (declarations)
+    EMIT_ALL(SIG_ANNOTATED, cm_ae, /**/, ;)
+
+    // Class Methods, Annotated declaration, Annotated definition.
+    // Declarations have extra annotations.
+    // (declarations)
+    EMIT_ALL(SIG_ANNOTATED, cm_ea, /**/, VL_PURE VL_MT_SAFE;)
+
+    // Class Methods (call test in header).
+    EMIT_ALL(SIG_ANNOTATED, cm_test_caller_smethod_hdr, /**/, {
+        VerilatedMutex m;
+
+        TestClass tc;
+        EMIT_ALL(CALL, tc.cm_au, m, ;)
+        EMIT_ALL(CALL, tc.cm_ua, m, ;)
+        EMIT_ALL(CALL, tc.cm_aa, m, ;)
+        EMIT_ALL(CALL, tc.cm_ae, m, ;)
+        EMIT_ALL(CALL, tc.cm_ea, m, ;)
+
+        TestClass* tcp = &tc;
+        EMIT_ALL(CALL, tcp->cm_au, m, ;)
+        EMIT_ALL(CALL, tcp->cm_ua, m, ;)
+        EMIT_ALL(CALL, tcp->cm_aa, m, ;)
+        EMIT_ALL(CALL, tcp->cm_ae, m, ;)
+        EMIT_ALL(CALL, tcp->cm_ea, m, ;)
+    })
+
+    // Class Methods (call test).
+    // (declaration)
+    EMIT_ALL(SIG_ANNOTATED, cm_test_caller_smethod, /**/, ;)
+
+    // Inline Class Methods.
+    EMIT_ALL(SIG_ANNOTATED, icm, /**/, {})
+
+    // Inline Class Methods (call test in header).
+    EMIT_ALL(SIG_ANNOTATED, icm_test_caller_smethod_hdr, /**/, {
+        VerilatedMutex m;
+
+        TestClass tc;
+        EMIT_ALL(CALL, tc.icm, m, ;)
+
+        TestClass* tcp = &tc;
+        EMIT_ALL(CALL, tcp->icm, m, ;)
+    })
+
+    // Inline Class Methods (call test).
+    // (declaration)
+    EMIT_ALL(SIG_ANNOTATED, icm_test_caller_smethod, /**/, ;)
+
+    void guarded_by_test_pass(GuardMe& guardme_arg) VL_MT_SAFE {
+        guardme_arg.safe_if_guarded_or_local();
+        int a = guardme_arg;
+
+        m_mtx.lock();
+        m_guardme.safe_if_guarded_or_local();
+        int b = m_guardme;
+        m_mtx.unlock();
+
+        GuardMe guardme_local;
+        guardme_local.safe_if_guarded_or_local();
+        int c = guardme_local;
+    }
+
+    void guarded_by_test_fail() VL_MT_SAFE {
+        m_guardme_unguarded.safe_if_guarded_or_local();
+        int a = m_guardme_unguarded;
+    }
+};
+
+#endif  // T_DIST_ATTRIBUTES_BAD_H_

test_regress/t/t_dist_attributes_bad.pl

@@ -0,0 +1,44 @@
+#!/usr/bin/env perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2022 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+scenarios(dist => 1);
+if ($ENV{VERILATOR_TEST_NO_ATTRIBUTES}) {
+    skip("Skipping due to VERILATOR_TEST_NO_ATTRIBUTES");
+} else {
+    check();
+}
+sub check {
+    my $root = "..";
+    my @srcfiles = glob("$root/test_regress/t/t_dist_attributes_bad.cpp");
+    my $srcfiles_str = join(" ", @srcfiles);
+    my $clang_args = "-I$root/include";
+
+    sub run_clang_check {
+        {
+            my $cmd = qq{python3 -c "from clang.cindex import Index; index = Index.create(); print(\\"Clang imported\\")";};
+            print "\t$cmd\n" if $::Debug;
+            my $out = `$cmd`;
+            if (!$out || $out !~ /Clang imported/) { skip("No libclang installed\n"); return 1; }
+        }
+        run(logfile => $Self->{run_log_filename},
+            tee => 1,
+            # With `--verilator-root` set to the current directory
+            # (i.e. `test_regress`) the script will skip annotation issues in
+            # headers from the `../include` directory.
+            cmd => ["python3", "$root/nodist/clang_check_attributes --verilator-root=. --cxxflags='$clang_args' $srcfiles_str"]);
+
+        files_identical($Self->{run_log_filename}, $Self->{golden_filename});
+    }
+
+    run_clang_check();
+}
+
+ok(1);
+1;