merge main into amd-staging (llvm#788)

Author: ronlieb

clang-tools-extra/docs/clang-tidy/checks/bugprone/implicit-widening-of-multiplication-result.rst

@@ -37,20 +37,20 @@ Options
 .. option:: UseCXXStaticCastsInCppSources
 
    When suggesting fix-its for C++ code, should C++-style ``static_cast<>()``'s
-   be suggested, or C-style casts. Defaults to ``true``.
+   be suggested, or C-style casts. Defaults to `true`.
 
 .. option:: UseCXXHeadersInCppSources
 
    When suggesting to include the appropriate header in C++ code,
    should ``<cstddef>`` header be suggested, or ``<stddef.h>``.
-   Defaults to ``true``.
+   Defaults to `true`.
 
 .. option:: IgnoreConstantIntExpr
 
    If the multiplication operands are compile-time constants (like literals or
    are ``constexpr``) and fit within the source expression type, do not emit a
    diagnostic or suggested fix.  Only considers expressions where the source
-   expression is a signed integer type.  Defaults to ``false``.
+   expression is a signed integer type.  Defaults to `false`.
 
 Examples:
 

clang-tools-extra/docs/clang-tidy/checks/cert/err33-c.rst

@@ -190,7 +190,7 @@ This check is an alias of check :doc:`bugprone-unused-return-value <../bugprone/
 with a fixed set of functions.
 
 Suppressing issues by casting to ``void`` is enabled by default and can be
-disabled by setting `AllowCastToVoid` option to ``false``.
+disabled by setting `AllowCastToVoid` option to `false`.
 
 The check corresponds to a part of CERT C Coding Standard rule `ERR33-C.
 Detect and handle standard library errors

clang-tools-extra/docs/clang-tidy/checks/modernize/loop-convert.rst

@@ -144,7 +144,7 @@ lives.
 
    When set to true convert loops when in C++20 or later mode using
    ``std::ranges::reverse_view``.
-   Default value is ``true``.
+   Default value is `true`.
 
 .. option:: MakeReverseRangeFunction
 

clang/docs/ClangFormatStyleOptions.rst

@@ -4786,17 +4786,20 @@ the configuration (without a prefix: ``Auto``).
 
   .. note::
 
-   You can also specify the language (``Cpp`` or ``ObjC``) for ``.h`` files
-   by adding a ``// clang-format Language:`` line before the first
+   You can specify the language (``C``, ``Cpp``, or ``ObjC``) for ``.h``
+   files by adding a ``// clang-format Language:`` line before the first
    non-comment (and non-empty) line, e.g. ``// clang-format Language: Cpp``.
 
   Possible values:
 
   * ``LK_None`` (in configuration: ``None``)
     Do not use.
 
+  * ``LK_C`` (in configuration: ``C``)
+    Should be used for C.
+
   * ``LK_Cpp`` (in configuration: ``Cpp``)
-    Should be used for C, C++.
+    Should be used for C++.
 
   * ``LK_CSharp`` (in configuration: ``CSharp``)
     Should be used for C#.

clang/docs/ReleaseNotes.rst

@@ -271,9 +271,10 @@ clang-format
 - Adds ``BreakBeforeTemplateCloser`` option.
 - Adds ``BinPackLongBracedList`` option to override bin packing options in
   long (20 item or more) braced list initializer lists.
-- Allow specifying the language (C++ or Objective-C) for a ``.h`` file by adding
-  a special comment (e.g. ``// clang-format Language: ObjC``) near the top of
-  the file.
+- Add the C language instead of treating it like C++.
+- Allow specifying the language (C, C++, or Objective-C) for a ``.h`` file by
+  adding a special comment (e.g. ``// clang-format Language: ObjC``) near the
+  top of the file.
 
 libclang
 --------

clang/include/clang/Format/Format.h

@@ -3318,7 +3318,9 @@ struct FormatStyle {
   enum LanguageKind : int8_t {
     /// Do not use.
     LK_None,
-    /// Should be used for C, C++.
+    /// Should be used for C.
+    LK_C,
+    /// Should be used for C++.
     LK_Cpp,
     /// Should be used for C#.
     LK_CSharp,
@@ -3343,7 +3345,9 @@ struct FormatStyle {
     /// https://sci-hub.st/10.1109/IEEESTD.2018.8299595
     LK_Verilog
   };
-  bool isCpp() const { return Language == LK_Cpp || Language == LK_ObjC; }
+  bool isCpp() const {
+    return Language == LK_Cpp || Language == LK_C || Language == LK_ObjC;
+  }
   bool isCSharp() const { return Language == LK_CSharp; }
   bool isJson() const { return Language == LK_Json; }
   bool isJavaScript() const { return Language == LK_JavaScript; }
@@ -3355,8 +3359,8 @@ struct FormatStyle {
 
   /// The language that this format style targets.
   /// \note
-  ///  You can also specify the language (``Cpp`` or ``ObjC``) for ``.h`` files
-  ///  by adding a ``// clang-format Language:`` line before the first
+  ///  You can specify the language (``C``, ``Cpp``, or ``ObjC``) for ``.h``
+  ///  files by adding a ``// clang-format Language:`` line before the first
   ///  non-comment (and non-empty) line, e.g. ``// clang-format Language: Cpp``.
   /// \endnote
   /// \version 3.5
@@ -5715,6 +5719,8 @@ FormatStyle::LanguageKind guessLanguage(StringRef FileName, StringRef Code);
 // Returns a string representation of ``Language``.
 inline StringRef getLanguageName(FormatStyle::LanguageKind Language) {
   switch (Language) {
+  case FormatStyle::LK_C:
+    return "C";
   case FormatStyle::LK_Cpp:
     return "C++";
   case FormatStyle::LK_CSharp:

clang/lib/AST/ByteCode/Interp.cpp

@@ -1015,11 +1015,14 @@ static bool RunDestructors(InterpState &S, CodePtr OpPC, const Block *B) {
   assert(Desc->isRecord() || Desc->isCompositeArray());
 
   if (Desc->isCompositeArray()) {
+    unsigned N = Desc->getNumElems();
+    if (N == 0)
+      return true;
     const Descriptor *ElemDesc = Desc->ElemDesc;
     assert(ElemDesc->isRecord());
 
     Pointer RP(const_cast<Block *>(B));
-    for (unsigned I = 0; I != Desc->getNumElems(); ++I) {
+    for (int I = static_cast<int>(N) - 1; I >= 0; --I) {
       if (!runRecordDestructor(S, OpPC, RP.atIndex(I).narrow(), ElemDesc))
         return false;
     }
@@ -1238,8 +1241,10 @@ static bool checkConstructor(InterpState &S, CodePtr OpPC, const Function *Func,
                              const Pointer &ThisPtr) {
   assert(Func->isConstructor());
 
-  const Descriptor *D = ThisPtr.getFieldDesc();
+  if (Func->getParentDecl()->isInvalidDecl())
+    return false;
 
+  const Descriptor *D = ThisPtr.getFieldDesc();
   // FIXME: I think this case is not 100% correct. E.g. a pointer into a
   // subobject of a composite array.
   if (!D->ElemRecord)
@@ -1377,6 +1382,18 @@ bool CallVirt(InterpState &S, CodePtr OpPC, const Function *Func,
   size_t ArgSize = Func->getArgSize() + VarArgSize;
   size_t ThisOffset = ArgSize - (Func->hasRVO() ? primSize(PT_Ptr) : 0);
   Pointer &ThisPtr = S.Stk.peek<Pointer>(ThisOffset);
+  const FunctionDecl *Callee = Func->getDecl();
+
+  // C++2a [class.abstract]p6:
+  //   the effect of making a virtual call to a pure virtual function [...] is
+  //   undefined
+  if (Callee->isPureVirtual()) {
+    S.FFDiag(S.Current->getSource(OpPC), diag::note_constexpr_pure_virtual_call,
+             1)
+        << Callee;
+    S.Note(Callee->getLocation(), diag::note_declared_at);
+    return false;
+  }
 
   const CXXRecordDecl *DynamicDecl = nullptr;
   {
@@ -1393,7 +1410,7 @@ bool CallVirt(InterpState &S, CodePtr OpPC, const Function *Func,
   assert(DynamicDecl);
 
   const auto *StaticDecl = cast<CXXRecordDecl>(Func->getParentDecl());
-  const auto *InitialFunction = cast<CXXMethodDecl>(Func->getDecl());
+  const auto *InitialFunction = cast<CXXMethodDecl>(Callee);
   const CXXMethodDecl *Overrider = S.getContext().getOverridingFunction(
       DynamicDecl, StaticDecl, InitialFunction);
 

clang/lib/Format/Format.cpp

@@ -401,6 +401,7 @@ template <> struct MappingTraits<FormatStyle::KeepEmptyLinesStyle> {
 
 template <> struct ScalarEnumerationTraits<FormatStyle::LanguageKind> {
   static void enumeration(IO &IO, FormatStyle::LanguageKind &Value) {
+    IO.enumCase(Value, "C", FormatStyle::LK_C);
     IO.enumCase(Value, "Cpp", FormatStyle::LK_Cpp);
     IO.enumCase(Value, "Java", FormatStyle::LK_Java);
     IO.enumCase(Value, "JavaScript", FormatStyle::LK_JavaScript);
@@ -3957,7 +3958,12 @@ LangOptions getFormattingLangOpts(const FormatStyle &Style) {
   LangOpts.Digraphs = LexingStd >= FormatStyle::LS_Cpp11;
 
   LangOpts.LineComment = 1;
-  LangOpts.CXXOperatorNames = Style.isCpp();
+
+  const auto Language = Style.Language;
+  LangOpts.C17 = Language == FormatStyle::LK_C;
+  LangOpts.CXXOperatorNames =
+      Language == FormatStyle::LK_Cpp || Language == FormatStyle::LK_ObjC;
+
   LangOpts.Bool = 1;
   LangOpts.ObjC = 1;
   LangOpts.MicrosoftExt = 1;    // To get kw___try, kw___finally.
@@ -3982,6 +3988,8 @@ const char *StyleOptionHelpDescription =
     "   --style=\"{BasedOnStyle: llvm, IndentWidth: 8}\"";
 
 static FormatStyle::LanguageKind getLanguageByFileName(StringRef FileName) {
+  if (FileName.ends_with(".c"))
+    return FormatStyle::LK_C;
   if (FileName.ends_with(".java"))
     return FormatStyle::LK_Java;
   if (FileName.ends_with_insensitive(".js") ||
@@ -4039,6 +4047,8 @@ static FormatStyle::LanguageKind getLanguageByComment(const Environment &Env) {
       continue;
 
     Text = Text.trim();
+    if (Text == "C")
+      return FormatStyle::LK_C;
     if (Text == "Cpp")
       return FormatStyle::LK_Cpp;
     if (Text == "ObjC")

clang/lib/Format/FormatToken.cpp

@@ -44,8 +44,7 @@ static SmallVector<StringRef> CppNonKeywordTypes = {
 bool FormatToken::isTypeName(const LangOptions &LangOpts) const {
   if (is(TT_TypeName) || Tok.isSimpleTypeSpecifier(LangOpts))
     return true;
-  const bool IsCpp = LangOpts.CXXOperatorNames;
-  return IsCpp && is(tok::identifier) &&
+  return (LangOpts.CXXOperatorNames || LangOpts.C17) && is(tok::identifier) &&
          std::binary_search(CppNonKeywordTypes.begin(),
                             CppNonKeywordTypes.end(), TokenText);
 }

clang/lib/Format/TokenAnnotator.cpp

@@ -129,7 +129,7 @@ class AnnotatingParser {
       : Style(Style), Line(Line), CurrentToken(Line.First), AutoFound(false),
         IsCpp(Style.isCpp()), LangOpts(getFormattingLangOpts(Style)),
         Keywords(Keywords), Scopes(Scopes), TemplateDeclarationDepth(0) {
-    assert(IsCpp == LangOpts.CXXOperatorNames);
+    assert(IsCpp == (LangOpts.CXXOperatorNames || LangOpts.C17));
     Contexts.push_back(Context(tok::unknown, 1, /*IsExpression=*/false));
     resetTokenMetadata();
   }
@@ -3821,7 +3821,7 @@ static bool isFunctionDeclarationName(const LangOptions &LangOpts,
   };
 
   const auto *Next = Current.Next;
-  const bool IsCpp = LangOpts.CXXOperatorNames;
+  const bool IsCpp = LangOpts.CXXOperatorNames || LangOpts.C17;
 
   // Find parentheses of parameter list.
   if (Current.is(tok::kw_operator)) {