Merge branch 'main' into amd-trunk-dev

.ci/generate-buildkite-pipeline-premerge

@@ -191,6 +191,9 @@ function keep-modified-projects() {
 }
 
 function check-targets() {
+  # Do not use "check-all" here because if there is "check-all" plus a
+  # project specific target like "check-clang", that project's tests
+  # will be run twice.
   projects=${@}
   for project in ${projects}; do
     case ${project} in
@@ -216,7 +219,7 @@ function check-targets() {
       echo "check-lldb"
     ;;
     pstl)
-      echo "check-all"
+      # Currently we do not run pstl tests in CI.
     ;;
     libclc)
       # Currently there is no testing for libclc.

.github/workflows/release-binaries.yml

@@ -328,7 +328,7 @@ jobs:
       run: |
         # Build some of the mlir tools that take a long time to link
         if [ "${{ needs.prepare.outputs.build-flang }}" = "true" ]; then
-          ninja -C ${{ steps.setup-stage.outputs.build-prefix }}/build/tools/clang/stage2-bins/ -j2 flang-new bbc
+          ninja -C ${{ steps.setup-stage.outputs.build-prefix }}/build/tools/clang/stage2-bins/ -j2 flang bbc
         fi
         ninja -C ${{ steps.setup-stage.outputs.build-prefix }}/build/tools/clang/stage2-bins/ \
             mlir-bytecode-parser-fuzzer \

clang-tools-extra/clang-apply-replacements/lib/Tooling/ApplyReplacements.cpp

@@ -148,11 +148,8 @@ groupReplacements(const TUReplacements &TUs, const TUDiagnostics &TUDs,
 
     if (auto Entry = SM.getFileManager().getOptionalFileRef(Path)) {
       if (SourceTU) {
-        auto &Replaces = DiagReplacements[*Entry];
-        auto It = Replaces.find(R);
-        if (It == Replaces.end())
-          Replaces.emplace(R, SourceTU);
-        else if (It->second != SourceTU)
+        auto [It, Inserted] = DiagReplacements[*Entry].try_emplace(R, SourceTU);
+        if (!Inserted && It->second != SourceTU)
           // This replacement is a duplicate of one suggested by another TU.
           return;
       }

clang-tools-extra/clang-change-namespace/ChangeNamespace.cpp

@@ -606,9 +606,8 @@ void ChangeNamespaceTool::run(
                  Result.Nodes.getNodeAs<DeclRefExpr>("func_ref")) {
     // If this reference has been processed as a function call, we do not
     // process it again.
-    if (ProcessedFuncRefs.count(FuncRef))
+    if (!ProcessedFuncRefs.insert(FuncRef).second)
       return;
-    ProcessedFuncRefs.insert(FuncRef);
     const auto *Func = Result.Nodes.getNodeAs<FunctionDecl>("func_decl");
     assert(Func);
     const auto *Context = Result.Nodes.getNodeAs<Decl>("dc");

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

@@ -146,12 +146,13 @@ void ForwardDeclarationNamespaceCheck::onEndOfTranslationUnit() {
       }
       // Check if a definition in another namespace exists.
       const auto DeclName = CurDecl->getName();
-      if (!DeclNameToDefinitions.contains(DeclName)) {
+      auto It = DeclNameToDefinitions.find(DeclName);
+      if (It == DeclNameToDefinitions.end()) {
         continue; // No definition in this translation unit, we can skip it.
       }
       // Make a warning for each definition with the same name (in other
       // namespaces).
-      const auto &Definitions = DeclNameToDefinitions[DeclName];
+      const auto &Definitions = It->second;
       for (const auto *Def : Definitions) {
         diag(CurDecl->getLocation(),
              "no definition found for %0, but a definition with "

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

@@ -9,6 +9,7 @@ add_clang_library(clangTidyPortabilityModule STATIC
   RestrictSystemIncludesCheck.cpp
   SIMDIntrinsicsCheck.cpp
   StdAllocatorConstCheck.cpp
+  TemplateVirtualMemberFunctionCheck.cpp
 
   LINK_LIBS
   clangTidy

clang-tools-extra/clang-tidy/portability/PortabilityTidyModule.cpp

@@ -12,6 +12,7 @@
 #include "RestrictSystemIncludesCheck.h"
 #include "SIMDIntrinsicsCheck.h"
 #include "StdAllocatorConstCheck.h"
+#include "TemplateVirtualMemberFunctionCheck.h"
 
 namespace clang::tidy {
 namespace portability {
@@ -25,6 +26,8 @@ class PortabilityModule : public ClangTidyModule {
         "portability-simd-intrinsics");
     CheckFactories.registerCheck<StdAllocatorConstCheck>(
         "portability-std-allocator-const");
+    CheckFactories.registerCheck<TemplateVirtualMemberFunctionCheck>(
+        "portability-template-virtual-member-function");
   }
 };
 

clang-tools-extra/clang-tidy/portability/TemplateVirtualMemberFunctionCheck.cpp

@@ -0,0 +1,44 @@
+//===--- TemplateVirtualMemberFunctionCheck.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 "TemplateVirtualMemberFunctionCheck.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::portability {
+namespace {
+AST_MATCHER(CXXMethodDecl, isUsed) { return Node.isUsed(); }
+} // namespace
+
+void TemplateVirtualMemberFunctionCheck::registerMatchers(MatchFinder *Finder) {
+  Finder->addMatcher(
+      cxxMethodDecl(ofClass(classTemplateSpecializationDecl(
+                                unless(isExplicitTemplateSpecialization()))
+                                .bind("specialization")),
+                    isVirtual(), unless(isUsed()),
+                    unless(cxxDestructorDecl(isDefaulted())))
+          .bind("method"),
+      this);
+}
+
+void TemplateVirtualMemberFunctionCheck::check(
+    const MatchFinder::MatchResult &Result) {
+  const auto *ImplicitSpecialization =
+      Result.Nodes.getNodeAs<ClassTemplateSpecializationDecl>("specialization");
+  const auto *MethodDecl = Result.Nodes.getNodeAs<CXXMethodDecl>("method");
+
+  diag(MethodDecl->getLocation(),
+       "unspecified virtual member function instantiation; the virtual "
+       "member function is not instantiated but it might be with a "
+       "different compiler");
+  diag(ImplicitSpecialization->getPointOfInstantiation(),
+       "template instantiated here", DiagnosticIDs::Note);
+}
+
+} // namespace clang::tidy::portability

clang-tools-extra/clang-tidy/portability/TemplateVirtualMemberFunctionCheck.h

@@ -0,0 +1,38 @@
+//===--- TemplateVirtualMemberFunctionCheck.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_PORTABILITY_TEMPLATEVIRTUALMEMBERFUNCTIONCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PORTABILITY_TEMPLATEVIRTUALMEMBERFUNCTIONCHECK_H
+
+#include "../ClangTidyCheck.h"
+
+namespace clang::tidy::portability {
+
+/// Upon instantiating a template class, non-virtual member functions don't have
+/// to be instantiated unless they are used. Virtual member function
+/// instantiation on the other hand is unspecified and depends on the
+/// implementation of the compiler. This check intends to find cases when a
+/// virtual member function is not instantiated but it might be with a different
+/// compiler.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/portability/template-virtual-member-function.html
+class TemplateVirtualMemberFunctionCheck : public ClangTidyCheck {
+public:
+  TemplateVirtualMemberFunctionCheck(StringRef Name, ClangTidyContext *Context)
+      : ClangTidyCheck(Name, Context) {}
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+  bool isLanguageVersionSupported(const LangOptions &LangOpts) const override {
+    return LangOpts.CPlusPlus;
+  }
+};
+
+} // namespace clang::tidy::portability
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PORTABILITY_TEMPLATEVIRTUALMEMBERFUNCTIONCHECK_H

clang-tools-extra/docs/ReleaseNotes.rst

@@ -121,6 +121,12 @@ New checks
   Gives warnings for tagged unions, where the number of tags is
   different from the number of data members inside the union.
 
+- New :doc:`portability-template-virtual-member-function
+  <clang-tidy/checks/portability/template-virtual-member-function>` check.
+
+  Finds cases when an uninstantiated virtual member function in a template class 
+  causes cross-compiler incompatibility.
+
 New check aliases
 ^^^^^^^^^^^^^^^^^
 

clang-tools-extra/docs/clang-tidy/checks/list.rst

@@ -348,6 +348,7 @@ Clang-Tidy Checks
    :doc:`portability-restrict-system-includes <portability/restrict-system-includes>`, "Yes"
    :doc:`portability-simd-intrinsics <portability/simd-intrinsics>`,
    :doc:`portability-std-allocator-const <portability/std-allocator-const>`,
+   :doc:`portability-template-virtual-member-function <portability/template-virtual-member-function>`,
    :doc:`readability-avoid-const-params-in-decls <readability/avoid-const-params-in-decls>`, "Yes"
    :doc:`readability-avoid-nested-conditional-operator <readability/avoid-nested-conditional-operator>`,
    :doc:`readability-avoid-return-with-void-value <readability/avoid-return-with-void-value>`, "Yes"

clang-tools-extra/docs/clang-tidy/checks/portability/template-virtual-member-function.rst

@@ -0,0 +1,37 @@
+.. title:: clang-tidy - portability-template-virtual-member-function
+
+portability-template-virtual-member-function
+============================================
+
+Finds cases when an uninstantiated virtual member function in a template class causes 
+cross-compiler incompatibility.
+
+Upon instantiating a template class, non-virtual member functions don't have to be 
+instantiated unless they are used. Virtual member function instantiation on the other hand 
+is unspecified and depends on the implementation of the compiler.
+
+In the following snippets the virtual member function is not instantiated by GCC and Clang,
+but it is instantiated by MSVC, so while the snippet is accepted by the former compilers,
+it is rejected by the latter.
+
+.. code:: c++
+
+    template<typename T>
+    struct CrossPlatformError {
+        virtual ~CrossPlatformError() = default;
+
+        static void used() {}
+
+        virtual void unused() {
+            T MSVCError = this;
+        };
+    };
+
+    int main() {
+        CrossPlatformError<int>::used();
+        return 0;
+    }
+
+Cross-platform projects that need to support MSVC on Windows might see compiler errors
+because certain virtual member functions are instantiated, which are not instantiated 
+by other compilers on other platforms. This check highlights such virtual member functions.