Merge remote-tracking branch 'upstream/release/21.x' into rustc/21.1-2025-08-01

Author: nikic

clang/docs/PointerAuthentication.rst

@@ -123,6 +123,8 @@ C++ Language Changes
   a perfect match (all conversion sequences are identity conversions) template candidates are not instantiated.
   Diagnostics that would have resulted from the instantiation of these template candidates are no longer
   produced. This aligns Clang closer to the behavior of GCC, and fixes (#GH62096), (#GH74581), and (#GH74581).
+- Implemented `P2719R5 Type-aware allocation and deallocation functions <https://wg21.link/P2719>`_
+  as an extension in all C++ language modes.
 
 C++2c Feature Support
 ^^^^^^^^^^^^^^^^^^^^^
@@ -359,6 +361,12 @@ Non-comprehensive list of changes in this release
   ARC-managed pointers and other pointer types. The prior behavior was overly
   strict and inconsistent with the ARC specification.
 
+- Use of ``__has_feature`` to detect the ``ptrauth_qualifier`` and ``ptrauth_intrinsics``
+  features has been deprecated, and is restricted to the arm64e target only. The
+  correct method to check for these features is to test for the ``__PTRAUTH__``
+  macro.
+
+
 New Compiler Flags
 ------------------
 
@@ -378,6 +386,11 @@ New Compiler Flags
 
 - New options ``-fthinlto-distributor=`` and ``-Xthinlto-distributor=`` added for Integrated Distributed ThinLTO (DTLTO). DTLTO enables the distribution of backend ThinLTO compilations via external distribution systems, such as Incredibuild, during the traditional link step. (#GH147265, `ThinLTODocs <https://clang.llvm.org/docs/ThinLTO.html#integrated-distributed-thinlto-dtlto>`_).
 
+- A new flag - `-static-libclosure` was introduced to support statically linking
+  the runtime for the Blocks extension on Windows. This flag currently only
+  changes the code generation, and even then, only on Windows. This does not
+  impact the linker behaviour like the other `-static-*` flags.
+
 Deprecated Compiler Flags
 -------------------------
 
@@ -676,7 +689,7 @@ Improvements to Clang's diagnostics
   #GH142457, #GH139913, #GH138850, #GH137867, #GH137860, #GH107840, #GH93308,
   #GH69470, #GH59391, #GH58172, #GH46215, #GH45915, #GH45891, #GH44490,
   #GH36703, #GH32903, #GH23312, #GH69874.
-  
+
 - Clang no longer emits a spurious -Wdangling-gsl warning in C++23 when
   iterating over an element of a temporary container in a range-based
   for loop.(#GH109793, #GH145164)
@@ -997,6 +1010,19 @@ Miscellaneous Clang Crashes Fixed
 OpenACC Specific Changes
 ------------------------
 
+- OpenACC support, enabled via `-fopenacc` has reached a level of completeness
+  to finally be at least notionally usable. Currently, the OpenACC 3.4
+  specification has been completely implemented for Sema and AST creation, so
+  nodes will show up in the AST after having been properly checked. Lowering is
+  currently a work in progress, with compute, loop, and combined constructs
+  partially implemented, plus a handful of data and executable constructs
+  implemented. Lowering will only work in Clang-IR mode (so only with a compiler
+  built with Clang-IR enabled, and with `-fclangir` used on the command line).
+  However, note that the Clang-IR implementation status is also quite partial,
+  so frequent 'not yet implemented' diagnostics should be expected.  Also, the
+  ACC MLIR dialect does not currently implement any lowering to LLVM-IR, so no
+  code generation is possible for OpenACC.
+
 Target Specific Changes
 -----------------------
 
@@ -1125,9 +1151,19 @@ CUDA/HIP Language Changes
 CUDA Support
 ^^^^^^^^^^^^
 
+PowerPC Support
+^^^^^^^^^^^^^^^
+
+* Add `__dmr1024` type for Dense Math Facility.
+* Add prototype for Dense Math Facility integer calculation builtins.
+
 AIX Support
 ^^^^^^^^^^^
 
+* Fixed `-print-runtime-dir` to fallback to the target subdirectory (rather than OS subdirectory) if the runtime path is not found.
+* Fixed `-print-runtime-dir` to find the correct runtime path if the triple has "unknown" as the environment component.
+* Changed AIX targets to use the per-target runtime directories for compiler runtimes (i.e. `lib/clang/20/lib/aix` became `lib/clang/21/lib/powerpc-ibm-aix` and `clang/21/lib/powerpc64-ibm-aix`).
+
 NetBSD Support
 ^^^^^^^^^^^^^^
 
@@ -1198,53 +1234,112 @@ Code Completion
 
 Static Analyzer
 ---------------
-- Fixed a crash when C++20 parenthesized initializer lists are used. This issue
-  was causing a crash in clang-tidy. (#GH136041)
 
 New features
 ^^^^^^^^^^^^
 
-- A new flag - `-static-libclosure` was introduced to support statically linking
-  the runtime for the Blocks extension on Windows. This flag currently only
-  changes the code generation, and even then, only on Windows. This does not
-  impact the linker behaviour like the other `-static-*` flags.
-- OpenACC support, enabled via `-fopenacc` has reached a level of completeness
-  to finally be at least notionally usable. Currently, the OpenACC 3.4
-  specification has been completely implemented for Sema and AST creation, so
-  nodes will show up in the AST after having been properly checked. Lowering is
-  currently a work in progress, with compute, loop, and combined constructs
-  partially implemented, plus a handful of data and executable constructs
-  implemented. Lowering will only work in Clang-IR mode (so only with a compiler
-  built with Clang-IR enabled, and with `-fclangir` used on the command line).
-  However, note that the Clang-IR implementation status is also quite partial,
-  so frequent 'not yet implemented' diagnostics should be expected.  Also, the
-  ACC MLIR dialect does not currently implement any lowering to LLVM-IR, so no
-  code generation is possible for OpenACC.
-- Implemented `P2719R5 Type-aware allocation and deallocation functions <https://wg21.link/P2719>`_
-  as an extension in all C++ language modes.
+- Added support for the ``[[clang::assume(cond)]]`` attribute, treating it as
+  ``__builtin_assume(cond)`` for better static analysis. (#GH129234)
 
+- Introduced per-entry-point statistics to provide more detailed analysis metrics.
+  Documentation: :doc:`analyzer/developer-docs/Statistics` (#GH131175)
+
+- Added time-trace scopes for high-level analyzer steps to improve performance
+  debugging. Documentation: :doc:`analyzer/developer-docs/PerformanceInvestigation`
+  (#GH125508, #GH125884)
+
+- Enhanced the ``check::BlockEntrance`` checker callback to provide more granular
+  control over block-level analysis.
+  `Documentation (check::BlockEntrance)
+  <https://clang.llvm.org/doxygen/CheckerDocumentation_8cpp_source.html>`_
+  (#GH140924)
+
+- Added a new checker ``core.FixedAddressDereference`` to detect dereferences
+  of fixed addresses, which can be useful for finding hard-coded memory
+  accesses. (#GH127191, #GH132404)
 
 Crash and bug fixes
 ^^^^^^^^^^^^^^^^^^^
 
-- Fixed a crash in ``UnixAPIMisuseChecker`` and ``MallocChecker`` when analyzing
+- Fixed a crash when C++20 parenthesized initializer lists are used.
+  This affected a crash of the well-known lambda overloaded pattern.
+  (#GH136041, #GH135665)
+
+- Dropped an unjustified assertion, that was triggered in ``BugReporterVisitors.cpp``
+  for variable initialization detection. (#GH125044)
+
+- Fixed a crash in ``unix.API`` and ``unix.Malloc`` when analyzing
   code with non-standard ``getline`` or ``getdelim`` function signatures. (#GH144884)
 
+- Fixed crashes involving ``__builtin_bit_cast``. (#GH139188)
+
+- ``__datasizeof`` (C++) and ``_Countof`` (C) no longer cause a failed assertion
+  when given an operand of VLA type. (#GH151711)
+
+- Fixed a crash in ``alpha.core.CastSize``. (#GH134387)
+
+- Some ``cplusplus.PlacementNew`` false positives were fixed. (#GH150161)
+
 Improvements
 ^^^^^^^^^^^^
 
+- Added option to assume at least one iteration in loops to reduce false positives.
+  (#GH125494)
+
 - The checker option ``optin.cplusplus.VirtualCall:PureOnly`` was removed,
-  because it had been deprecated since 2019 and it is completely useless (it
-  was kept only for compatibility with pre-2019 versions, setting it to true is
-  equivalent to completely disabling the checker).
+  because it had been deprecated since 2019. (#GH131823)
+
+- Enhanced the ``core.StackAddressEscape`` to detect more cases of stack address
+  escapes, including return values for child stack frames. (#GH126620, #GH126986)
+
+- Improved the ``unix.BlockInCriticalSection`` to recognize ``O_NONBLOCK``
+  streams and suppress reports in those cases. (#GH127049)
+
+- Better support for lambda-converted function pointers in analysis. (#GH144906)
+
+- Improved modeling of ``getcwd`` function in ``unix.StdCLibraryFunctions`` checker.
+  (#GH141076)
+
+- Enhanced the ``optin.core.EnumCastOutOfRange`` checker to ignore ``[[clang::flag_enum]]``
+  enums. (#GH141232)
+
+- Improved handling of structured bindings captured by lambdas. (#GH132579, #GH91835)
+
+- Fixed unnamed bitfield handling in ``optin.cplusplus.UninitializedObject``. (#GH132427, #GH132001)
+
+- Enhanced iterator checker modeling for ``insert`` operations. (#GH132596)
+
+- Improved ``format`` attribute handling in ``optin.taint.GenericTaint``. (#GH132765)
+
+- Added support for ``consteval`` in ``ConditionBRVisitor::VisitTerminator``.
+  (#GH146859, #GH139130)
+
+- C standard streams are no longer invalidated by all C library function calls.
+  (#GH147766)
+
+- Enhanced store management with region-store-binding-limit to improve performance.
+  See `region-store-max-binding-fanout
+  <https://clang.llvm.org/docs/analyzer/user-docs/Options.html#region-store-max-binding-fanout>`_
+  config option. Overriding these options are discouraged, unless you know what you do.
+  (#GH127602)
+
+- Updated undefined assignment checker (``core.uninitialized.Assign``) diagnostics
+  to avoid using the term ``garbage``. (#GH126596)
+
+- Fixed false memory leak reports involving placement new. (#GH144341)
+
+- Avoided unnecessary super region invalidation in ``unix.cstring.*`` checkers.
+  (#GH146212, #GH143807)
+
+- Enhanced handling of tainted division-by-zero error paths in the
+  ``optin.taint.TaintedDiv`` checker. (#GH144491)
 
 Moved checkers
 ^^^^^^^^^^^^^^
 
-- After lots of improvements, the checker ``alpha.security.ArrayBoundV2`` is
+- After lots of improvements, the checker ``alpha.security.ArrayBoundV2`` was
   renamed to ``security.ArrayBound``. As this checker is stable now, the old
-  checker ``alpha.security.ArrayBound`` (which was searching for the same kind
-  of bugs with an different, simpler and less accurate algorithm) is removed.
+  checker ``alpha.security.ArrayBound`` was removed.
 
 .. _release-notes-sanitizers:
 

clang/docs/ReleaseNotes.rst

@@ -143,7 +143,7 @@ class APValue {
     AddrLabelDiff
   };
 
-  class LValueBase {
+  class alignas(uint64_t) LValueBase {
     typedef llvm::PointerUnion<const ValueDecl *, const Expr *, TypeInfoLValue,
                                DynamicAllocLValue>
         PtrTy;

clang/include/clang/AST/APValue.h

@@ -147,14 +147,17 @@ FEATURE(type_sanitizer, LangOpts.Sanitize.has(SanitizerKind::Type))
 FEATURE(thread_sanitizer, LangOpts.Sanitize.has(SanitizerKind::Thread))
 FEATURE(dataflow_sanitizer, LangOpts.Sanitize.has(SanitizerKind::DataFlow))
 FEATURE(scudo, LangOpts.Sanitize.hasOneOf(SanitizerKind::Scudo))
-FEATURE(ptrauth_intrinsics, LangOpts.PointerAuthIntrinsics)
-EXTENSION(ptrauth_qualifier, LangOpts.PointerAuthIntrinsics)
+FEATURE(ptrauth_intrinsics, LangOpts.PointerAuthIntrinsics &&
+                            PP.getTargetInfo().getTriple().isOSDarwin())
+FEATURE(ptrauth_qualifier, LangOpts.PointerAuthIntrinsics &&
+                           PP.getTargetInfo().getTriple().isOSDarwin())
 FEATURE(ptrauth_calls, LangOpts.PointerAuthCalls)
 FEATURE(ptrauth_returns, LangOpts.PointerAuthReturns)
 FEATURE(ptrauth_vtable_pointer_address_discrimination, LangOpts.PointerAuthVTPtrAddressDiscrimination)
 FEATURE(ptrauth_vtable_pointer_type_discrimination, LangOpts.PointerAuthVTPtrTypeDiscrimination)
 FEATURE(ptrauth_type_info_vtable_pointer_discrimination, LangOpts.PointerAuthTypeInfoVTPtrDiscrimination)
 FEATURE(ptrauth_member_function_pointer_type_discrimination, LangOpts.PointerAuthCalls)
+FEATURE(ptrauth_signed_block_descriptors, LangOpts.PointerAuthBlockDescriptorPointers)
 FEATURE(ptrauth_function_pointer_type_discrimination, LangOpts.PointerAuthFunctionTypeDiscrimination)
 FEATURE(ptrauth_indirect_gotos, LangOpts.PointerAuthIndirectGotos)
 FEATURE(ptrauth_init_fini, LangOpts.PointerAuthInitFini)
@@ -163,7 +166,7 @@ FEATURE(ptrauth_elf_got, LangOpts.PointerAuthELFGOT)
 
 FEATURE(ptrauth_objc_isa, LangOpts.PointerAuthObjcIsa)
 FEATURE(ptrauth_objc_interface_sel, LangOpts.PointerAuthObjcInterfaceSel)
-FEATURE(ptrauth_objc_signable_class, true)
+FEATURE(ptrauth_objc_signable_class, LangOpts.PointerAuthIntrinsics)
 FEATURE(ptrauth_objc_method_list_pointer, LangOpts.PointerAuthCalls)
 
 EXTENSION(swiftcc,

clang/include/clang/Basic/Features.def

@@ -138,6 +138,8 @@ LANGOPT(PointerAuthObjcInterfaceSel, 1, 0, NotCompatible, "authentication of SEL
 LANGOPT(PointerAuthObjcInterfaceSelKey, 16, 0, NotCompatible, "authentication key for SEL fields of ObjC interfaces")
 LANGOPT(PointerAuthObjcClassROPointers, 1, 0, Benign, "class_ro_t pointer authentication")
 
+LANGOPT(PointerAuthBlockDescriptorPointers, 1, 0, NotCompatible, "enable signed block descriptors")
+
 LANGOPT(DoubleSquareBracketAttributes, 1, 0, NotCompatible, "'[[]]' attributes extension for all language standard modes")
 LANGOPT(ExperimentalLateParseAttributes, 1, 0, NotCompatible, "experimental late parsing of attributes")
 

clang/include/clang/Basic/LangOptions.def

@@ -23,6 +23,10 @@
 
 namespace clang {
 
+/// Constant discriminator to be used with block descriptor pointers. The value
+/// is ptrauth_string_discriminator("block_descriptor")
+constexpr uint16_t BlockDescriptorConstantDiscriminator = 0xC0BB;
+
 /// Constant discriminator to be used with function pointers in .init_array and
 /// .fini_array. The value is ptrauth_string_discriminator("init_fini")
 constexpr uint16_t InitFiniPointerConstantDiscriminator = 0xD9D4;
@@ -223,6 +227,18 @@ struct PointerAuthOptions {
   /// The ABI for function addresses in .init_array and .fini_array
   PointerAuthSchema InitFiniPointers;
 
+  /// The ABI for block invocation function pointers.
+  PointerAuthSchema BlockInvocationFunctionPointers;
+
+  /// The ABI for block object copy/destroy function pointers.
+  PointerAuthSchema BlockHelperFunctionPointers;
+
+  /// The ABI for __block variable copy/destroy function pointers.
+  PointerAuthSchema BlockByrefHelperFunctionPointers;
+
+  /// The ABI for pointers to block descriptors.
+  PointerAuthSchema BlockDescriptorPointers;
+
   /// The ABI for Objective-C method lists.
   PointerAuthSchema ObjCMethodListFunctionPointers;
 

clang/include/clang/Basic/PointerAuthOptions.h

@@ -4527,6 +4527,7 @@ defm aarch64_jump_table_hardening: OptInCC1FFlag<"aarch64-jump-table-hardening",
 defm ptrauth_objc_isa : OptInCC1FFlag<"ptrauth-objc-isa", "Enable signing and authentication of Objective-C object's 'isa' field">;
 defm ptrauth_objc_interface_sel : OptInCC1FFlag<"ptrauth-objc-interface-sel", "Enable signing and authentication of Objective-C object's 'SEL' fields">;
 defm ptrauth_objc_class_ro : OptInCC1FFlag<"ptrauth-objc-class-ro", "Enable signing and authentication for ObjC class_ro pointers">;
+defm ptrauth_block_descriptor_pointers : OptInCC1FFlag<"ptrauth-block-descriptor-pointers", "Enable signing and authentication of block descriptors">;
 }
 
 def fenable_matrix : Flag<["-"], "fenable-matrix">, Group<f_Group>,

clang/include/clang/Driver/Options.td

@@ -143,9 +143,6 @@ class Lexer : public PreprocessorLexer {
   /// True if this is the first time we're lexing the input file.
   bool IsFirstTimeLexingFile;
 
-  /// True if current lexing token is the first pp-token.
-  bool IsFirstPPToken;
-
   // NewLinePtr - A pointer to new line character '\n' being lexed. For '\r\n',
   // it also points to '\n.'
   const char *NewLinePtr;