Merge remote-tracking branch 'upstream/release/20.x' into rustc/20.1-2025-02-13

Author: nikic

.github/workflows/release-binaries.yml

@@ -138,6 +138,11 @@ jobs:
             arches=arm64
           else
             arches=x86_64
+            # Disable Flang builds on macOS x86_64.  The FortranLower library takes
+            # 2-3 hours to build on macOS, much slower than on Linux.
+            # The long build time causes the release build to time out on x86_64,
+            # so we need to disable flang there.
+            target_cmake_flags="$target_cmake_flags -DLLVM_RELEASE_ENABLE_PROJECTS='clang;lld;lldb;clang-tools-extra;polly;mlir'"
           fi
           target_cmake_flags="$target_cmake_flags -DBOOTSTRAP_DARWIN_osx_ARCHS=$arches -DBOOTSTRAP_DARWIN_osx_BUILTIN_ARCHS=$arches"
         fi

clang/cmake/caches/Release.cmake

@@ -29,14 +29,21 @@ endfunction()
 # cache file to CMake via -C. e.g.
 #
 # cmake -D LLVM_RELEASE_ENABLE_PGO=ON -C Release.cmake
+
+set (DEFAULT_PROJECTS "clang;lld;lldb;clang-tools-extra;polly;mlir;flang")
+# bolt only supports ELF, so only enable it for Linux.
+if (${CMAKE_HOST_SYSTEM_NAME} MATCHES "Linux")
+  list(APPEND DEFAULT_PROJECTS "bolt")
+endif()
+
 set (DEFAULT_RUNTIMES "compiler-rt;libcxx")
 if (NOT WIN32)
   list(APPEND DEFAULT_RUNTIMES "libcxxabi" "libunwind")
 endif()
 set(LLVM_RELEASE_ENABLE_LTO THIN CACHE STRING "")
 set(LLVM_RELEASE_ENABLE_PGO ON CACHE BOOL "")
 set(LLVM_RELEASE_ENABLE_RUNTIMES ${DEFAULT_RUNTIMES} CACHE STRING "")
-set(LLVM_RELEASE_ENABLE_PROJECTS "clang;lld;lldb;clang-tools-extra;bolt;polly;mlir;flang" CACHE STRING "")
+set(LLVM_RELEASE_ENABLE_PROJECTS ${DEFAULT_PROJECTS} CACHE STRING "")
 # Note we don't need to add install here, since it is one of the pre-defined
 # steps.
 set(LLVM_RELEASE_FINAL_STAGE_TARGETS "clang;package;check-all;check-llvm;check-clang" CACHE STRING "")
@@ -48,10 +55,8 @@ set(CLANG_ENABLE_BOOTSTRAP ON CACHE BOOL "")
 
 set(STAGE1_PROJECTS "clang")
 
-# Building Flang on Windows requires compiler-rt, so we need to build it in
-# stage1.  compiler-rt is also required for building the Flang tests on
-# macOS.
-set(STAGE1_RUNTIMES "compiler-rt")
+# Build all runtimes so we can statically link them into the stage2 compiler.
+set(STAGE1_RUNTIMES "compiler-rt;libcxx;libcxxabi;libunwind")
 
 if (LLVM_RELEASE_ENABLE_PGO)
   list(APPEND STAGE1_PROJECTS "lld")
@@ -90,9 +95,20 @@ else()
   set(CLANG_BOOTSTRAP_TARGETS ${LLVM_RELEASE_FINAL_STAGE_TARGETS} CACHE STRING "")
 endif()
 
+if (LLVM_RELEASE_ENABLE_LTO)
+  # Enable LTO for the runtimes.  We need to configure stage1 clang to default
+  # to using lld as the linker because the stage1 toolchain will be used to
+  # build and link the runtimes.
+  # FIXME: We can't use LLVM_ENABLE_LTO=Thin here, because it causes the CMake
+  # step for the libcxx build to fail.  CMAKE_INTERPROCEDURAL_OPTIMIZATION does
+  # enable ThinLTO, though.
+  set(RUNTIMES_CMAKE_ARGS "-DCMAKE_INTERPROCEDURAL_OPTIMIZATION=ON -DLLVM_ENABLE_LLD=ON" CACHE STRING "")
+endif()
+
 # Stage 1 Common Config
 set(LLVM_ENABLE_RUNTIMES ${STAGE1_RUNTIMES} CACHE STRING "")
 set(LLVM_ENABLE_PROJECTS ${STAGE1_PROJECTS} CACHE STRING "")
+set(LIBCXX_STATICALLY_LINK_ABI_IN_STATIC_LIBRARY ON CACHE STRING "")
 
 # stage2-instrumented and Final Stage Config:
 # Options that need to be set in both the instrumented stage (if we are doing
@@ -102,13 +118,29 @@ set_instrument_and_final_stage_var(LLVM_ENABLE_LTO "${LLVM_RELEASE_ENABLE_LTO}"
 if (LLVM_RELEASE_ENABLE_LTO)
   set_instrument_and_final_stage_var(LLVM_ENABLE_LLD "ON" BOOL)
 endif()
+set_instrument_and_final_stage_var(LLVM_ENABLE_LIBCXX "ON" BOOL)
+set_instrument_and_final_stage_var(LLVM_STATIC_LINK_CXX_STDLIB "ON" BOOL)
+set(RELEASE_LINKER_FLAGS "-rtlib=compiler-rt --unwindlib=libunwind")
+if(NOT ${CMAKE_HOST_SYSTEM_NAME} MATCHES "Darwin")
+  set(RELEASE_LINKER_FLAGS "${RELEASE_LINKER_FLAGS} -static-libgcc")
+endif()
+
+# Set flags for bolt
+if (${CMAKE_HOST_SYSTEM_NAME} MATCHES "Linux")
+  set(RELEASE_LINKER_FLAGS "${RELEASE_LINKER_FLAGS} -Wl,--emit-relocs,-znow")
+endif()
+
+set_instrument_and_final_stage_var(CMAKE_EXE_LINKER_FLAGS ${RELEASE_LINKER_FLAGS} STRING)
+set_instrument_and_final_stage_var(CMAKE_SHARED_LINKER_FLAGS ${RELEASE_LINKER_FLAGS} STRING)
+set_instrument_and_final_stage_var(CMAKE_MODULE_LINKER_FLAGS ${RELEASE_LINKER_FLAGS} STRING)
 
 # Final Stage Config (stage2)
 set_final_stage_var(LLVM_ENABLE_RUNTIMES "${LLVM_RELEASE_ENABLE_RUNTIMES}" STRING)
 set_final_stage_var(LLVM_ENABLE_PROJECTS "${LLVM_RELEASE_ENABLE_PROJECTS}" STRING)
+if (${CMAKE_HOST_SYSTEM_NAME} MATCHES "Linux")
+  set_final_stage_var(CLANG_BOLT "INSTRUMENT" STRING)
+endif()
 set_final_stage_var(CPACK_GENERATOR "TXZ" STRING)
 set_final_stage_var(CPACK_ARCHIVE_THREADS "0" STRING)
 
-if(${CMAKE_HOST_SYSTEM_NAME} MATCHES "Darwin")
-  set_final_stage_var(LLVM_USE_STATIC_ZSTD "ON" BOOL)
-endif()
+set_final_stage_var(LLVM_USE_STATIC_ZSTD "ON" BOOL)

clang/docs/ReleaseNotes.rst

@@ -897,6 +897,8 @@ Bug Fixes in This Version
 - No longer return ``false`` for ``noexcept`` expressions involving a
   ``delete`` which resolves to a destroying delete but the type of the object
   being deleted has a potentially throwing destructor (#GH118660).
+- Clang now outputs correct values when #embed data contains bytes with negative
+  signed char values (#GH102798).
 
 Bug Fixes to Compiler Builtins
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1053,6 +1055,9 @@ Bug Fixes to C++ Support
   template parameter. Now, such expression can be used with ``static_assert`` and ``constexpr``. (#GH123498)
 - Correctly determine the implicit constexprness of lambdas in dependent contexts. (#GH97958) (#GH114234)
 - Fix that some dependent immediate expressions did not cause immediate escalation (#GH119046)
+- Fixed a substitution bug in transforming CTAD aliases when the type alias contains a non-pack template argument
+  corresponding to a pack parameter (#GH124715)
+- Clang is now better at keeping track of friend function template instance contexts. (#GH55509)
 
 Bug Fixes to AST Handling
 ^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1264,6 +1269,8 @@ CUDA Support
 
 AIX Support
 ^^^^^^^^^^^
+- Fixed the ``-print-runtime-dir`` option.
+- Enable continuous profile syncing feature on AIX.
 
 NetBSD Support
 ^^^^^^^^^^^^^^

clang/docs/UsersManual.rst

@@ -2489,6 +2489,82 @@ are listed below.
 
     $ clang -fuse-ld=lld -Oz -Wl,--icf=safe -fcodegen-data-use code.cc
 
+.. _strict_aliasing:
+
+Strict Aliasing
+---------------
+
+The C and C++ standards require accesses to objects in memory to use l-values of
+an appropriate type for the object. This is called *strict aliasing* or
+*type-based alias analysis*. Strict aliasing enhances a variety of powerful
+memory optimizations, including reordering, combining, and eliminating memory
+accesses. These optimizations can lead to unexpected behavior in code that
+violates the strict aliasing rules. For example:
+
+.. code-block:: c++
+
+    void advance(size_t *index, double *data) {
+      double value = data[*index];
+      /* Clang may assume that this store does not change the contents of `data`. */
+      *index += 1;
+      /* Clang may assume that this store does not change the contents of `index`. */
+      data[*index] = value;
+      /* Either of these facts may create significant optimization opportunities
+       if Clang is able to inline this function. */
+  }
+
+Strict aliasing can be explicitly enabled with ``-fstrict-aliasing`` and
+disabled with ``-fno-strict-aliasing``. ``clang-cl`` defaults to
+``-fno-strict-aliasing``; see . Otherwise, Clang defaults to ``-fstrict-aliasing``.
+
+C and C++ specify slightly different rules for strict aliasing. To improve
+language interoperability, Clang allows two types to alias if either language
+would permit it. This includes applying the C++ similar types rule to C,
+allowing ``int **`` to alias ``int const * const *``. Clang also relaxes the
+standard aliasing rules in the following ways:
+
+* All integer types of the same size are permitted to alias each other,
+  including signed and unsigned types.
+* ``void*`` is permitted to alias any pointer type, ``void**`` is permitted to
+  alias any pointer to pointer type, and so on.
+
+Code which violates strict aliasing has undefined behavior. A program that
+works in one version of Clang may not work in another because of changes to the
+optimizer. Clang provides a :doc:`TypeSanitizer` to help detect
+violations of the strict aliasing rules, but it is currently still experimental.
+Code that is known to violate strict aliasing should generally be built with
+``-fno-strict-aliasing`` if the violation cannot be fixed.
+
+Clang supports several ways to fix a violation of strict aliasing:
+
+* L-values of the character types ``char`` and ``unsigned char`` (as well as
+  other types, depending on the standard) are permitted to access objects of
+  any type.
+
+* Library functions such as ``memcpy`` and ``memset`` are specified as treating
+  memory as characters and therefore are not limited by strict aliasing. If a
+  value of one type must be reinterpreted as another (e.g. to read the bits of a
+  floating-point number), use ``memcpy`` to copy the representation to an object
+  of the destination type. This has no overhead over a direct l-value access
+  because Clang should reliably optimize calls to these functions to use simple
+  loads and stores when they are used with small constant sizes.
+
+* The attribute ``may_alias`` can be added to a ``typedef`` to give l-values of
+  that type the same aliasing power as the character types.
+
+Clang makes a best effort to avoid obvious miscompilations from strict aliasing
+by only considering type information when it cannot prove that two accesses must
+refer to the same memory. However, it is not recommended that programmers
+intentionally rely on this instead of using one of the solutions above because
+it is too easy for the compiler's analysis to be blocked in surprising ways.
+
+In Clang 20, Clang strengthened its implementation of strict aliasing for
+accesses of pointer type. Previously, all accesses of pointer type were
+permitted to alias each other, but Clang now distinguishes different pointers
+by their pointee type, except as limited by the relaxations around qualifiers
+and ``void*`` described above. The previous behavior of treating all pointers as
+aliasing can be restored using ``-fno-pointer-tbaa``.
+
 Profile Guided Optimization
 ---------------------------
 
@@ -5272,12 +5348,6 @@ The Visual C++ Toolset has a slightly more elaborate mechanism for detection.
 Restrictions and Limitations compared to Clang
 ----------------------------------------------
 
-Strict Aliasing
-^^^^^^^^^^^^^^^
-
-Strict aliasing (TBAA) is always off by default in clang-cl. Whereas in clang,
-strict aliasing is turned on by default for all optimization levels.
-
-To enable LLVM optimizations based on strict aliasing rules (e.g., optimizations
-based on type of expressions in C/C++), user will need to explicitly pass
-`-fstrict-aliasing` to clang-cl.
+Strict aliasing (TBAA) is always off by default in clang-cl whereas in clang,
+strict aliasing is turned on by default for all optimization levels. For more
+details, see :ref:`Strict aliasing <strict_aliasing>`.

clang/include/clang/AST/Decl.h

@@ -2298,6 +2298,13 @@ class FunctionDecl : public DeclaratorDecl,
     FunctionDeclBits.IsLateTemplateParsed = ILT;
   }
 
+  bool isInstantiatedFromMemberTemplate() const {
+    return FunctionDeclBits.IsInstantiatedFromMemberTemplate;
+  }
+  void setInstantiatedFromMemberTemplate(bool Val = true) {
+    FunctionDeclBits.IsInstantiatedFromMemberTemplate = Val;
+  }
+
   /// Whether this function is "trivial" in some specialized C++ senses.
   /// Can only be true for default constructors, copy constructors,
   /// copy assignment operators, and destructors.  Not meaningful until

clang/include/clang/AST/DeclBase.h

@@ -1780,6 +1780,8 @@ class DeclContext {
     uint64_t HasImplicitReturnZero : 1;
     LLVM_PREFERRED_TYPE(bool)
     uint64_t IsLateTemplateParsed : 1;
+    LLVM_PREFERRED_TYPE(bool)
+    uint64_t IsInstantiatedFromMemberTemplate : 1;
 
     /// Kind of contexpr specifier as defined by ConstexprSpecKind.
     LLVM_PREFERRED_TYPE(ConstexprSpecKind)
@@ -1830,7 +1832,7 @@ class DeclContext {
   };
 
   /// Number of inherited and non-inherited bits in FunctionDeclBitfields.
-  enum { NumFunctionDeclBits = NumDeclContextBits + 31 };
+  enum { NumFunctionDeclBits = NumDeclContextBits + 32 };
 
   /// Stores the bits used by CXXConstructorDecl. If modified
   /// NumCXXConstructorDeclBits and the accessor
@@ -1841,12 +1843,12 @@ class DeclContext {
     LLVM_PREFERRED_TYPE(FunctionDeclBitfields)
     uint64_t : NumFunctionDeclBits;
 
-    /// 20 bits to fit in the remaining available space.
+    /// 19 bits to fit in the remaining available space.
     /// Note that this makes CXXConstructorDeclBitfields take
     /// exactly 64 bits and thus the width of NumCtorInitializers
     /// will need to be shrunk if some bit is added to NumDeclContextBitfields,
     /// NumFunctionDeclBitfields or CXXConstructorDeclBitfields.
-    uint64_t NumCtorInitializers : 17;
+    uint64_t NumCtorInitializers : 16;
     LLVM_PREFERRED_TYPE(bool)
     uint64_t IsInheritingConstructor : 1;
 
@@ -1860,7 +1862,7 @@ class DeclContext {
   };
 
   /// Number of inherited and non-inherited bits in CXXConstructorDeclBitfields.
-  enum { NumCXXConstructorDeclBits = NumFunctionDeclBits + 20 };
+  enum { NumCXXConstructorDeclBits = NumFunctionDeclBits + 19 };
 
   /// Stores the bits used by ObjCMethodDecl.
   /// If modified NumObjCMethodDeclBits and the accessor

clang/include/clang/AST/DeclTemplate.h

@@ -1011,6 +1011,26 @@ class FunctionTemplateDecl : public RedeclarableTemplateDecl {
     return getTemplatedDecl()->isThisDeclarationADefinition();
   }
 
+  bool isCompatibleWithDefinition() const {
+    return getTemplatedDecl()->isInstantiatedFromMemberTemplate() ||
+           isThisDeclarationADefinition();
+  }
+
+  // This bit closely tracks 'RedeclarableTemplateDecl::InstantiatedFromMember',
+  // except this is per declaration, while the redeclarable field is
+  // per chain. This indicates a template redeclaration which
+  // is compatible with the definition, in the non-trivial case
+  // where this is not already a definition.
+  // This is only really needed for instantiating the definition of friend
+  // function templates, which can have redeclarations in different template
+  // contexts.
+  // The bit is actually stored in the FunctionDecl for space efficiency
+  // reasons.
+  void setInstantiatedFromMemberTemplate(FunctionTemplateDecl *D) {
+    getTemplatedDecl()->setInstantiatedFromMemberTemplate();
+    RedeclarableTemplateDecl::setInstantiatedFromMemberTemplate(D);
+  }
+
   /// Return the specialization with the provided arguments if it exists,
   /// otherwise return the insertion point.
   FunctionDecl *findSpecialization(ArrayRef<TemplateArgument> Args,
@@ -1841,15 +1861,23 @@ class ClassTemplateSpecializationDecl : public CXXRecordDecl,
   LLVM_PREFERRED_TYPE(TemplateSpecializationKind)
   unsigned SpecializationKind : 3;
 
+  /// Indicate that we have matched a parameter pack with a non pack
+  /// argument, when the opposite match is also allowed (strict pack match).
+  /// This needs to be cached as deduction is performed during declaration,
+  /// and we need the information to be preserved so that it is consistent
+  /// during instantiation.
+  bool MatchedPackOnParmToNonPackOnArg : 1;
+
 protected:
   ClassTemplateSpecializationDecl(ASTContext &Context, Kind DK, TagKind TK,
                                   DeclContext *DC, SourceLocation StartLoc,
                                   SourceLocation IdLoc,
                                   ClassTemplateDecl *SpecializedTemplate,
                                   ArrayRef<TemplateArgument> Args,
+                                  bool MatchedPackOnParmToNonPackOnArg,
                                   ClassTemplateSpecializationDecl *PrevDecl);
 
-  explicit ClassTemplateSpecializationDecl(ASTContext &C, Kind DK);
+  ClassTemplateSpecializationDecl(ASTContext &C, Kind DK);
 
 public:
   friend class ASTDeclReader;
@@ -1859,7 +1887,7 @@ class ClassTemplateSpecializationDecl : public CXXRecordDecl,
   Create(ASTContext &Context, TagKind TK, DeclContext *DC,
          SourceLocation StartLoc, SourceLocation IdLoc,
          ClassTemplateDecl *SpecializedTemplate,
-         ArrayRef<TemplateArgument> Args,
+         ArrayRef<TemplateArgument> Args, bool MatchedPackOnParmToNonPackOnArg,
          ClassTemplateSpecializationDecl *PrevDecl);
   static ClassTemplateSpecializationDecl *CreateDeserialized(ASTContext &C,
                                                              GlobalDeclID ID);
@@ -1930,6 +1958,10 @@ class ClassTemplateSpecializationDecl : public CXXRecordDecl,
     SpecializationKind = TSK;
   }
 
+  bool hasMatchedPackOnParmToNonPackOnArg() const {
+    return MatchedPackOnParmToNonPackOnArg;
+  }
+
   /// Get the point of instantiation (if any), or null if none.
   SourceLocation getPointOfInstantiation() const {
     return PointOfInstantiation;

clang/include/clang/Basic/BuiltinsNVPTX.td

@@ -21,12 +21,14 @@ class SM<string version, list<SMFeatures> newer_list> : SMFeatures {
                         !strconcat(f, "|", newer.Features));
 }
 
+let Features = "sm_120a" in def SM_120a : SMFeatures;
+let Features = "sm_101a" in def SM_101a : SMFeatures;
 let Features = "sm_100a" in def SM_100a : SMFeatures;
-
-def SM_100 : SM<"100", [SM_100a]>;
-
 let Features = "sm_90a" in def SM_90a : SMFeatures;
 
+def SM_120 : SM<"120", [SM_120a]>;
+def SM_101 : SM<"101", [SM_101a, SM_120]>;
+def SM_100 : SM<"100", [SM_100a, SM_101]>;
 def SM_90 : SM<"90", [SM_90a, SM_100]>;
 def SM_89 : SM<"89", [SM_90]>;
 def SM_87 : SM<"87", [SM_89]>;

clang/include/clang/Basic/Cuda.h

@@ -82,6 +82,10 @@ enum class OffloadArch {
   SM_90a,
   SM_100,
   SM_100a,
+  SM_101,
+  SM_101a,
+  SM_120,
+  SM_120a,
   GFX600,
   GFX601,
   GFX602,

clang/include/clang/Sema/Sema.h

@@ -13491,8 +13491,8 @@ class Sema final : public SemaBase {
   bool InstantiateClassTemplateSpecialization(
       SourceLocation PointOfInstantiation,
       ClassTemplateSpecializationDecl *ClassTemplateSpec,
-      TemplateSpecializationKind TSK, bool Complain = true,
-      bool PrimaryHasMatchedPackOnParmToNonPackOnArg = false);
+      TemplateSpecializationKind TSK, bool Complain,
+      bool PrimaryHasMatchedPackOnParmToNonPackOnArg);
 
   /// Instantiates the definitions of all of the member
   /// of the given class, which is an instantiation of a class template