Merge branch 'main' into tracking

Author: RKSimon

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

@@ -555,22 +555,15 @@ bool NarrowingConversionsCheck::handleConditionalOperator(
     // We have an expression like so: `output = cond ? lhs : rhs`
     // From the point of view of narrowing conversion we treat it as two
     // expressions `output = lhs` and `output = rhs`.
-    handleConditionalOperatorArgument(Context, Lhs, CO->getLHS());
-    handleConditionalOperatorArgument(Context, Lhs, CO->getRHS());
+    handleBinaryOperator(Context, CO->getLHS()->getExprLoc(), Lhs,
+                         *CO->getLHS());
+    handleBinaryOperator(Context, CO->getRHS()->getExprLoc(), Lhs,
+                         *CO->getRHS());
     return true;
   }
   return false;
 }
 
-void NarrowingConversionsCheck::handleConditionalOperatorArgument(
-    const ASTContext &Context, const Expr &Lhs, const Expr *Arg) {
-  if (const auto *ICE = llvm::dyn_cast<ImplicitCastExpr>(Arg))
-    if (!Arg->getIntegerConstantExpr(Context))
-      Arg = ICE->getSubExpr();
-
-  handleBinaryOperator(Context, Arg->getExprLoc(), Lhs, *Arg);
-}
-
 void NarrowingConversionsCheck::handleImplicitCast(
     const ASTContext &Context, const ImplicitCastExpr &Cast) {
   if (Cast.getExprLoc().isMacroID())

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

@@ -85,8 +85,6 @@ class NarrowingConversionsCheck : public ClangTidyCheck {
   bool handleConditionalOperator(const ASTContext &Context, const Expr &Lhs,
                                  const Expr &Rhs);
 
-  void handleConditionalOperatorArgument(const ASTContext &Context,
-                                         const Expr &Lhs, const Expr *Arg);
   void handleImplicitCast(const ASTContext &Context,
                           const ImplicitCastExpr &Cast);
 

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

@@ -105,11 +105,15 @@ void TaggedUnionMemberCountCheck::storeOptions(
 
 void TaggedUnionMemberCountCheck::registerMatchers(MatchFinder *Finder) {
 
-  auto UnionField = fieldDecl(hasType(qualType(
-      hasCanonicalType(recordType(hasDeclaration(recordDecl(isUnion())))))));
+  auto NotFromSystemHeaderOrStdNamespace =
+      unless(anyOf(isExpansionInSystemHeader(), isInStdNamespace()));
 
-  auto EnumField = fieldDecl(hasType(
-      qualType(hasCanonicalType(enumType(hasDeclaration(enumDecl()))))));
+  auto UnionField =
+      fieldDecl(hasType(qualType(hasCanonicalType(recordType(hasDeclaration(
+          recordDecl(isUnion(), NotFromSystemHeaderOrStdNamespace)))))));
+
+  auto EnumField = fieldDecl(hasType(qualType(hasCanonicalType(
+      enumType(hasDeclaration(enumDecl(NotFromSystemHeaderOrStdNamespace)))))));
 
   auto HasOneUnionField = fieldCountOfKindIsOne(UnionField, UnionMatchBindName);
   auto HasOneEnumField = fieldCountOfKindIsOne(EnumField, TagMatchBindName);

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

@@ -236,7 +236,7 @@ def print_profile_data(aggregated_data: Dict[str, float]) -> None:
         checkers.items(), key=lambda x: x[1]["user"] + x[1]["sys"], reverse=True
     )
 
-    def print_stderr(*args, **kwargs) -> None:
+    def print_stderr(*args: Any, **kwargs: Any) -> None:
         print(*args, file=sys.stderr, **kwargs)
 
     print_stderr(

clang-tools-extra/docs/ReleaseNotes.rst

@@ -134,10 +134,6 @@ Changes in existing checks
   <clang-tidy/checks/bugprone/infinite-loop>` check by adding detection for
   variables introduced by structured bindings.
 
-- Improved :doc:`bugprone-narrowing-conversions
-  <clang-tidy/checks/bugprone/narrowing-conversions>` check by fixing
-  false positive from analysis of a conditional expression in C.
-
 - Improved :doc:`bugprone-reserved-identifier
   <clang-tidy/checks/bugprone/reserved-identifier>` check by ignoring
   declarations in system headers.
@@ -146,6 +142,12 @@ Changes in existing checks
   <clang-tidy/checks/bugprone/signed-char-misuse>` check by fixing
   false positives on C23 enums with the fixed underlying type of signed char.
 
+- Improved :doc:`bugprone-tagged-union-member-count
+  <clang-tidy/checks/bugprone/tagged-union-member-count>` by fixing a false
+  positive when enums or unions from system header files or the ``std``
+  namespace are treated as the tag or the data part of a user-defined
+  tagged union respectively.
+
 - Improved :doc:`bugprone-unhandled-self-assignment
   <clang-tidy/checks/bugprone/unhandled-self-assignment>` check by adding
   an additional matcher that generalizes the copy-and-swap idiom pattern

clang-tools-extra/docs/clang-tidy/checks/bugprone/tagged-union-member-count.rst

@@ -9,6 +9,8 @@ different from the number of data members inside the union.
 A struct or a class is considered to be a tagged union if it has
 exactly one union data member and exactly one enum data member and
 any number of other data members that are neither unions or enums.
+Furthermore, the types of the union and the enum members must 
+not come from system header files nor the ``std`` namespace.
 
 Example:
 
@@ -28,6 +30,25 @@ Example:
     } Data;
   };
 
+The following example illustrates the exception for unions and enums from
+system header files and the ``std`` namespace.
+
+.. code-block:: c++
+
+  #include <pthread.h>
+
+  struct NotTaggedUnion {
+    enum MyEnum { MyEnumConstant1, MyEnumConstant2 } En;
+    pthread_mutex_t Mutex;
+  };
+
+The ``pthread_mutex_t`` type may be defined as a union behind a ``typedef``,
+in which case the check could mistake this type as a user-defined tagged union.
+After all, it has exactly one enum data member and exactly one union data member.
+To avoid false-positive cases originating from this, unions and enums from
+system headers and the ``std`` namespace are ignored when pinpointing the
+union part and the enum part of a potential user-defined tagged union.
+
 How enum constants are counted
 ------------------------------
 

clang-tools-extra/test/clang-tidy/checkers/bugprone/Inputs/tagged-union-member-count/stdnamespace.h

@@ -0,0 +1,12 @@
+#define __SIZEOF_PTHREAD_MUTEX_T 40
+
+namespace std {
+  typedef union {
+    struct __pthread_mutex_s {
+      int __lock;
+      unsigned int __count;
+    } __data;
+    char __size[__SIZEOF_PTHREAD_MUTEX_T];
+    long int __align;
+  } pthread_mutex_t;
+};

clang-tools-extra/test/clang-tidy/checkers/bugprone/Inputs/tagged-union-member-count/system/pthread.h

@@ -0,0 +1,10 @@
+#define __SIZEOF_PTHREAD_MUTEX_T 40
+
+typedef union {
+  struct __pthread_mutex_s {
+    int __lock;
+    unsigned int __count;
+  } __data;
+  char __size[__SIZEOF_PTHREAD_MUTEX_T];
+  long int __align;
+} pthread_mutex_t;