Merge from 'master' to 'sycl-web' (#1)

  CONFLICT (content): Merge conflict in clang/lib/CodeGen/CGLoopInfo.cpp

Author: linkren

clang-tools-extra/clang-tidy/ClangTidy.cpp

@@ -110,6 +110,9 @@ class ErrorReporter {
     DiagOpts->ShowColors = Context.getOptions().UseColor.getValueOr(
         llvm::sys::Process::StandardOutHasColors());
     DiagPrinter->BeginSourceFile(LangOpts);
+    if (DiagOpts->ShowColors && !llvm::sys::Process::StandardOutIsDisplayed()) {
+      llvm::sys::Process::UseANSIEscapeCodes(true);
+    }
   }
 
   SourceManager &getSourceManager() { return SourceMgr; }

clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp

@@ -40,6 +40,7 @@
 #include "PosixReturnCheck.h"
 #include "RedundantBranchConditionCheck.h"
 #include "ReservedIdentifierCheck.h"
+#include "SignalHandlerCheck.h"
 #include "SignedCharMisuseCheck.h"
 #include "SizeofContainerCheck.h"
 #include "SizeofExpressionCheck.h"
@@ -133,6 +134,7 @@ class BugproneModule : public ClangTidyModule {
         "bugprone-posix-return");
     CheckFactories.registerCheck<ReservedIdentifierCheck>(
         "bugprone-reserved-identifier");
+    CheckFactories.registerCheck<SignalHandlerCheck>("bugprone-signal-handler");
     CheckFactories.registerCheck<SignedCharMisuseCheck>(
         "bugprone-signed-char-misuse");
     CheckFactories.registerCheck<SizeofContainerCheck>(

clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt

@@ -35,6 +35,7 @@ add_clang_library(clangTidyBugproneModule
   PosixReturnCheck.cpp
   RedundantBranchConditionCheck.cpp
   ReservedIdentifierCheck.cpp
+  SignalHandlerCheck.cpp
   SignedCharMisuseCheck.cpp
   SizeofContainerCheck.cpp
   SizeofExpressionCheck.cpp

clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp

@@ -0,0 +1,186 @@
+//===--- SignalHandlerCheck.cpp - clang-tidy ------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "SignalHandlerCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/RecursiveASTVisitor.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/Analysis/CallGraph.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallVector.h"
+#include <iterator>
+#include <queue>
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace bugprone {
+
+static bool isSystemCall(const FunctionDecl *FD) {
+  // Find a possible redeclaration in system header.
+  // FIXME: Looking at the canonical declaration is not the most exact way
+  // to do this.
+
+  // Most common case will be inclusion directly from a header.
+  // This works fine by using canonical declaration.
+  // a.c
+  // #include <sysheader.h>
+
+  // Next most common case will be extern declaration.
+  // Can't catch this with either approach.
+  // b.c
+  // extern void sysfunc(void);
+
+  // Canonical declaration is the first found declaration, so this works.
+  // c.c
+  // #include <sysheader.h>
+  // extern void sysfunc(void); // redecl won't matter
+
+  // This does not work with canonical declaration.
+  // Probably this is not a frequently used case but may happen (the first
+  // declaration can be in a non-system header for example).
+  // d.c
+  // extern void sysfunc(void); // Canonical declaration, not in system header.
+  // #include <sysheader.h>
+
+  return FD->getASTContext().getSourceManager().isInSystemHeader(
+      FD->getCanonicalDecl()->getLocation());
+}
+
+AST_MATCHER(FunctionDecl, isSystemCall) { return isSystemCall(&Node); }
+
+// This is the  minimal set of safe functions.
+// FIXME: Add checker option to allow a POSIX compliant extended set.
+llvm::StringSet<> SignalHandlerCheck::StrictConformingFunctions{
+    "signal", "abort", "_Exit", "quick_exit"};
+
+SignalHandlerCheck::SignalHandlerCheck(StringRef Name,
+                                       ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context) {}
+
+bool SignalHandlerCheck::isLanguageVersionSupported(
+    const LangOptions &LangOpts) const {
+  // FIXME: Make the checker useful on C++ code.
+  if (LangOpts.CPlusPlus)
+    return false;
+
+  return true;
+}
+
+void SignalHandlerCheck::registerMatchers(MatchFinder *Finder) {
+  auto SignalFunction = functionDecl(hasAnyName("::signal", "::std::signal"),
+                                     parameterCountIs(2), isSystemCall());
+  auto HandlerExpr =
+      declRefExpr(hasDeclaration(functionDecl().bind("handler_decl")),
+                  unless(isExpandedFromMacro("SIG_IGN")),
+                  unless(isExpandedFromMacro("SIG_DFL")))
+          .bind("handler_expr");
+  Finder->addMatcher(
+      callExpr(callee(SignalFunction), hasArgument(1, HandlerExpr))
+          .bind("register_call"),
+      this);
+}
+
+void SignalHandlerCheck::check(const MatchFinder::MatchResult &Result) {
+  const auto *SignalCall = Result.Nodes.getNodeAs<CallExpr>("register_call");
+  const auto *HandlerDecl =
+      Result.Nodes.getNodeAs<FunctionDecl>("handler_decl");
+  const auto *HandlerExpr = Result.Nodes.getNodeAs<DeclRefExpr>("handler_expr");
+
+  // Visit each function encountered in the callgraph only once.
+  llvm::DenseSet<const FunctionDecl *> SeenFunctions;
+
+  // The worklist of the callgraph visitation algorithm.
+  std::deque<const CallExpr *> CalledFunctions;
+
+  auto ProcessFunction = [&](const FunctionDecl *F, const Expr *CallOrRef) {
+    // Ensure that canonical declaration is used.
+    F = F->getCanonicalDecl();
+
+    // Do not visit function if already encountered.
+    if (!SeenFunctions.insert(F).second)
+      return true;
+
+    // Check if the call is allowed.
+    // Non-system calls are not considered.
+    if (isSystemCall(F)) {
+      if (isSystemCallAllowed(F))
+        return true;
+
+      reportBug(F, CallOrRef, SignalCall, HandlerDecl);
+
+      return false;
+    }
+
+    // Get the body of the encountered non-system call function.
+    const FunctionDecl *FBody;
+    if (!F->hasBody(FBody)) {
+      reportBug(F, CallOrRef, SignalCall, HandlerDecl);
+      return false;
+    }
+
+    // Collect all called functions.
+    auto Matches = match(decl(forEachDescendant(callExpr().bind("call"))),
+                         *FBody, FBody->getASTContext());
+    for (const auto &Match : Matches) {
+      const auto *CE = Match.getNodeAs<CallExpr>("call");
+      if (isa<FunctionDecl>(CE->getCalleeDecl()))
+        CalledFunctions.push_back(CE);
+    }
+
+    return true;
+  };
+
+  if (!ProcessFunction(HandlerDecl, HandlerExpr))
+    return;
+
+  // Visit the definition of every function referenced by the handler function.
+  // Check for allowed function calls.
+  while (!CalledFunctions.empty()) {
+    const CallExpr *FunctionCall = CalledFunctions.front();
+    CalledFunctions.pop_front();
+    // At insertion we have already ensured that only function calls are there.
+    const auto *F = cast<FunctionDecl>(FunctionCall->getCalleeDecl());
+
+    if (!ProcessFunction(F, FunctionCall))
+      break;
+  }
+}
+
+bool SignalHandlerCheck::isSystemCallAllowed(const FunctionDecl *FD) const {
+  const IdentifierInfo *II = FD->getIdentifier();
+  // Unnamed functions are not explicitly allowed.
+  if (!II)
+    return false;
+
+  // FIXME: Improve for C++ (check for namespace).
+  if (StrictConformingFunctions.count(II->getName()))
+    return true;
+
+  return false;
+}
+
+void SignalHandlerCheck::reportBug(const FunctionDecl *CalledFunction,
+                                   const Expr *CallOrRef,
+                                   const CallExpr *SignalCall,
+                                   const FunctionDecl *HandlerDecl) {
+  diag(CallOrRef->getBeginLoc(),
+       "%0 may not be asynchronous-safe; "
+       "calling it from a signal handler may be dangerous")
+      << CalledFunction;
+  diag(SignalCall->getSourceRange().getBegin(),
+       "signal handler registered here", DiagnosticIDs::Note);
+  diag(HandlerDecl->getBeginLoc(), "handler function declared here",
+       DiagnosticIDs::Note);
+}
+
+} // namespace bugprone
+} // namespace tidy
+} // namespace clang

clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.h

@@ -0,0 +1,42 @@
+//===--- SignalHandlerCheck.h - clang-tidy ----------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_SIGNALHANDLERCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_SIGNALHANDLERCHECK_H
+
+#include "../ClangTidyCheck.h"
+#include "llvm/ADT/StringSet.h"
+
+namespace clang {
+namespace tidy {
+namespace bugprone {
+
+/// Checker for signal handler functions.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/bugprone-signal-handler-check.html
+class SignalHandlerCheck : public ClangTidyCheck {
+public:
+  SignalHandlerCheck(StringRef Name, ClangTidyContext *Context);
+  bool isLanguageVersionSupported(const LangOptions &LangOpts) const override;
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+
+private:
+  void reportBug(const FunctionDecl *CalledFunction, const Expr *CallOrRef,
+                 const CallExpr *SignalCall, const FunctionDecl *HandlerDecl);
+  bool isSystemCallAllowed(const FunctionDecl *FD) const;
+
+  static llvm::StringSet<> StrictConformingFunctions;
+};
+
+} // namespace bugprone
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_SIGNALHANDLERCHECK_H

clang-tools-extra/clang-tidy/cert/CERTTidyModule.cpp

@@ -11,6 +11,7 @@
 #include "../ClangTidyModuleRegistry.h"
 #include "../bugprone/BadSignalToKillThreadCheck.h"
 #include "../bugprone/ReservedIdentifierCheck.h"
+#include "../bugprone/SignalHandlerCheck.h"
 #include "../bugprone/SignedCharMisuseCheck.h"
 #include "../bugprone/SpuriouslyWakeUpFunctionsCheck.h"
 #include "../bugprone/UnhandledSelfAssignmentCheck.h"
@@ -109,6 +110,8 @@ class CERTModule : public ClangTidyModule {
     // POS
     CheckFactories.registerCheck<bugprone::BadSignalToKillThreadCheck>(
         "cert-pos44-c");
+    // SIG
+    CheckFactories.registerCheck<bugprone::SignalHandlerCheck>("cert-sig30-c");
     // STR
     CheckFactories.registerCheck<bugprone::SignedCharMisuseCheck>(
         "cert-str34-c");

clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp

@@ -168,6 +168,16 @@ each source file in its parent directories.
 )"),
                                    cl::init(""), cl::cat(ClangTidyCategory));
 
+static cl::opt<std::string> ConfigFile("config-file", cl::desc(R"(
+Specify the path of .clang-tidy or custom config file:
+ e.g. --config-file=/some/path/myTidyConfigFile
+This option internally works exactly the same way as
+ --config option after reading specified config file.
+Use either --config-file or --config, not both.
+)"),
+                                       cl::init(""),
+                                       cl::cat(ClangTidyCategory));
+
 static cl::opt<bool> DumpConfig("dump-config", cl::desc(R"(
 Dumps configuration in the YAML format to
 stdout. This option can be used along with a
@@ -302,19 +312,41 @@ static std::unique_ptr<ClangTidyOptionsProvider> createOptionsProvider(
   if (UseColor.getNumOccurrences() > 0)
     OverrideOptions.UseColor = UseColor;
 
-  if (!Config.empty()) {
-    if (llvm::ErrorOr<ClangTidyOptions> ParsedConfig =
-            parseConfiguration(Config)) {
+  auto LoadConfig = [&](StringRef Configuration)
+      -> std::unique_ptr<ClangTidyOptionsProvider> {
+    llvm::ErrorOr<ClangTidyOptions> ParsedConfig =
+        parseConfiguration(Configuration);
+    if (ParsedConfig)
       return std::make_unique<ConfigOptionsProvider>(
           GlobalOptions,
           ClangTidyOptions::getDefaults().mergeWith(DefaultOptions, 0),
           *ParsedConfig, OverrideOptions, std::move(FS));
-    } else {
-      llvm::errs() << "Error: invalid configuration specified.\n"
-                   << ParsedConfig.getError().message() << "\n";
+    llvm::errs() << "Error: invalid configuration specified.\n"
+                 << ParsedConfig.getError().message() << "\n";
+    return nullptr;
+  };
+
+  if (ConfigFile.getNumOccurrences() > 0) {
+    if (Config.getNumOccurrences() > 0) {
+      llvm::errs() << "Error: --config-file and --config are "
+                      "mutually exclusive. Specify only one.\n";
       return nullptr;
     }
+
+    llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> Text =
+        llvm::MemoryBuffer::getFile(ConfigFile.c_str());
+    if (std::error_code EC = Text.getError()) {
+      llvm::errs() << "Error: can't read config-file '" << ConfigFile
+                   << "': " << EC.message() << "\n";
+      return nullptr;
+    }
+
+    return LoadConfig((*Text)->getBuffer());
   }
+
+  if (Config.getNumOccurrences() > 0)
+    return LoadConfig(Config);
+
   return std::make_unique<FileOptionsProvider>(GlobalOptions, DefaultOptions,
                                                 OverrideOptions, std::move(FS));
 }

clang-tools-extra/clang-tidy/tool/run-clang-tidy.py

@@ -83,7 +83,7 @@ def get_tidy_invocation(f, clang_tidy_binary, checks, tmpdir, build_path,
                         header_filter, allow_enabling_alpha_checkers,
                         extra_arg, extra_arg_before, quiet, config):
   """Gets a command line for clang-tidy."""
-  start = [clang_tidy_binary]
+  start = [clang_tidy_binary, '--use-color']
   if allow_enabling_alpha_checkers:
     start.append('-allow-enabling-analyzer-alpha-checkers')
   if header_filter is not None:

clang-tools-extra/clangd/AST.cpp

@@ -282,21 +282,20 @@ std::string printNamespaceScope(const DeclContext &DC) {
   return "";
 }
 
-llvm::Optional<SymbolID> getSymbolID(const Decl *D) {
+SymbolID getSymbolID(const Decl *D) {
   llvm::SmallString<128> USR;
   if (index::generateUSRForDecl(D, USR))
-    return None;
+    return {};
   return SymbolID(USR);
 }
 
-llvm::Optional<SymbolID> getSymbolID(const llvm::StringRef MacroName,
-                                     const MacroInfo *MI,
-                                     const SourceManager &SM) {
+SymbolID getSymbolID(const llvm::StringRef MacroName, const MacroInfo *MI,
+                     const SourceManager &SM) {
   if (MI == nullptr)
-    return None;
+    return {};
   llvm::SmallString<128> USR;
   if (index::generateUSRForMacro(MacroName, MI->getDefinitionLoc(), SM, USR))
-    return None;
+    return {};
   return SymbolID(USR);
 }