Merge branch 'main' into hgh/libcxx/P2255R2-A_type_trait_to_detect_reference_binding_to_temporary

Author: H-G-Hristov

clang-tools-extra/clang-tidy/performance/UnnecessaryValueParamCheck.cpp

@@ -7,7 +7,6 @@
 //===----------------------------------------------------------------------===//
 
 #include "UnnecessaryValueParamCheck.h"
-
 #include "../utils/DeclRefExprUtils.h"
 #include "../utils/FixItHintUtils.h"
 #include "../utils/Matchers.h"
@@ -30,14 +29,6 @@ std::string paramNameOrIndex(StringRef Name, size_t Index) {
       .str();
 }
 
-bool isReferencedOutsideOfCallExpr(const FunctionDecl &Function,
-                                   ASTContext &Context) {
-  auto Matches = match(declRefExpr(to(functionDecl(equalsNode(&Function))),
-                                   unless(hasAncestor(callExpr()))),
-                       Context);
-  return !Matches.empty();
-}
-
 bool hasLoopStmtAncestor(const DeclRefExpr &DeclRef, const Decl &Decl,
                          ASTContext &Context) {
   auto Matches = match(
@@ -155,12 +146,9 @@ void UnnecessaryValueParamCheck::handleConstRefFix(const FunctionDecl &Function,
   // Do not propose fixes when:
   // 1. the ParmVarDecl is in a macro, since we cannot place them correctly
   // 2. the function is virtual as it might break overrides
-  // 3. the function is referenced outside of a call expression within the
-  //    compilation unit as the signature change could introduce build errors.
-  // 4. the function is an explicit template/ specialization.
+  // 3. the function is an explicit template/ specialization.
   const auto *Method = llvm::dyn_cast<CXXMethodDecl>(&Function);
   if (Param.getBeginLoc().isMacroID() || (Method && Method->isVirtual()) ||
-      isReferencedOutsideOfCallExpr(Function, Context) ||
       Function.getTemplateSpecializationKind() == TSK_ExplicitSpecialization)
     return;
   for (const auto *FunctionDecl = &Function; FunctionDecl != nullptr;

clang-tools-extra/docs/ReleaseNotes.rst

@@ -115,6 +115,11 @@ Changes in existing checks
   <clang-tidy/checks/misc/redundant-expression>` check by providing additional
   examples and fixing some macro related false positives.
 
+- Improved :doc:`performance/unnecessary-value-param
+  <clang-tidy/checks/performance/unnecessary-value-param>` check performance by
+  tolerating fix-it breaking compilation when functions is used as pointers 
+  to avoid matching usage of functions within the current compilation unit.
+
 Removed checks
 ^^^^^^^^^^^^^^
 

clang-tools-extra/docs/clang-tidy/checks/performance/unnecessary-value-param.rst

@@ -54,6 +54,10 @@ Will become:
     Field = std::move(Value);
   }
 
+Because the fix-it needs to change the signature of the function, it may break
+builds if the function is used in multiple translation units or some codes
+depends on funcion signatures.
+
 Options
 -------
 

clang-tools-extra/test/clang-tidy/checkers/performance/unnecessary-value-param.cpp

@@ -332,11 +332,7 @@ void PositiveNonConstDeclaration(const ExpensiveToCopyType A) {
 
 void PositiveOnlyMessageAsReferencedInCompilationUnit(ExpensiveToCopyType A) {
   // CHECK-MESSAGES: [[@LINE-1]]:75: warning: the parameter 'A' is copied
-  // CHECK-FIXES: void PositiveOnlyMessageAsReferencedInCompilationUnit(ExpensiveToCopyType A) {
-}
-
-void ReferenceFunctionOutsideOfCallExpr() {
-  void (*ptr)(ExpensiveToCopyType) = &PositiveOnlyMessageAsReferencedInCompilationUnit;
+  // CHECK-FIXES: void PositiveOnlyMessageAsReferencedInCompilationUnit(const ExpensiveToCopyType& A) {
 }
 
 void PositiveMessageAndFixAsFunctionIsCalled(ExpensiveToCopyType A) {

clang/lib/StaticAnalyzer/Checkers/UndefinedAssignmentChecker.cpp

@@ -23,7 +23,7 @@ using namespace ento;
 namespace {
 class UndefinedAssignmentChecker
   : public Checker<check::Bind> {
-  const BugType BT{this, "Assigned value is garbage or undefined"};
+  const BugType BT{this, "Assigned value is uninitialized"};
 
 public:
   void checkBind(SVal location, SVal val, const Stmt *S,
@@ -57,8 +57,7 @@ void UndefinedAssignmentChecker::checkBind(SVal location, SVal val,
 
   while (StoreE) {
     if (const UnaryOperator *U = dyn_cast<UnaryOperator>(StoreE)) {
-      OS << "The expression is an uninitialized value. "
-            "The computed value will also be garbage";
+      OS << "The expression uses uninitialized memory";
 
       ex = U->getSubExpr();
       break;
@@ -67,8 +66,8 @@ void UndefinedAssignmentChecker::checkBind(SVal location, SVal val,
     if (const BinaryOperator *B = dyn_cast<BinaryOperator>(StoreE)) {
       if (B->isCompoundAssignmentOp()) {
         if (C.getSVal(B->getLHS()).isUndef()) {
-          OS << "The left expression of the compound assignment is an "
-                "uninitialized value. The computed value will also be garbage";
+          OS << "The left expression of the compound assignment uses "
+             << "uninitialized memory";
           ex = B->getLHS();
           break;
         }
@@ -89,7 +88,7 @@ void UndefinedAssignmentChecker::checkBind(SVal location, SVal val,
         for (auto *I : CD->inits()) {
           if (I->getInit()->IgnoreImpCasts() == StoreE) {
             OS << "Value assigned to field '" << I->getMember()->getName()
-               << "' in implicit constructor is garbage or undefined";
+               << "' in implicit constructor is uninitialized";
             break;
           }
         }

clang/test/Analysis/Inputs/expected-plists/edges-new.mm.plist

@@ -2578,17 +2578,17 @@
      </array>
      <key>depth</key><integer>0</integer>
      <key>extended_message</key>
-     <string>The left expression of the compound assignment is an uninitialized value. The computed value will also be garbage</string>
+     <string>The left expression of the compound assignment uses uninitialized memory</string>
      <key>message</key>
-     <string>The left expression of the compound assignment is an uninitialized value. The computed value will also be garbage</string>
+     <string>The left expression of the compound assignment uses uninitialized memory</string>
     </dict>
    </array>
-   <key>description</key><string>The left expression of the compound assignment is an uninitialized value. The computed value will also be garbage</string>
+   <key>description</key><string>The left expression of the compound assignment uses uninitialized memory</string>
    <key>category</key><string>Logic error</string>
-   <key>type</key><string>Assigned value is garbage or undefined</string>
+   <key>type</key><string>Assigned value is uninitialized</string>
    <key>check_name</key><string>core.uninitialized.Assign</string>
    <!-- This hash is experimental and going to change! -->
-   <key>issue_hash_content_of_line_in_context</key><string>025372576cd3ba6716044f93a51c978c</string>
+   <key>issue_hash_content_of_line_in_context</key><string>324827600c298776167cd9562f71bda6</string>
   <key>issue_context_kind</key><string>function</string>
   <key>issue_context</key><string>test_objc_fast_enumeration_2</string>
   <key>issue_hash_function_offset</key><string>5</string>

clang/test/Analysis/Inputs/expected-plists/plist-output.m.plist

@@ -5864,17 +5864,17 @@
      </array>
      <key>depth</key><integer>0</integer>
      <key>extended_message</key>
-     <string>The left expression of the compound assignment is an uninitialized value. The computed value will also be garbage</string>
+     <string>The left expression of the compound assignment uses uninitialized memory</string>
      <key>message</key>
-     <string>The left expression of the compound assignment is an uninitialized value. The computed value will also be garbage</string>
+     <string>The left expression of the compound assignment uses uninitialized memory</string>
     </dict>
    </array>
-   <key>description</key><string>The left expression of the compound assignment is an uninitialized value. The computed value will also be garbage</string>
+   <key>description</key><string>The left expression of the compound assignment uses uninitialized memory</string>
    <key>category</key><string>Logic error</string>
-   <key>type</key><string>Assigned value is garbage or undefined</string>
+   <key>type</key><string>Assigned value is uninitialized</string>
    <key>check_name</key><string>core.uninitialized.Assign</string>
    <!-- This hash is experimental and going to change! -->
-   <key>issue_hash_content_of_line_in_context</key><string>21c774309bdfd487c3d09a61a671bbcc</string>
+   <key>issue_hash_content_of_line_in_context</key><string>faa8858031ed123ff98cc23cf14d462f</string>
   <key>issue_context_kind</key><string>function</string>
   <key>issue_context</key><string>test_loop_fast_enumeration</string>
   <key>issue_hash_function_offset</key><string>5</string>

clang/test/Analysis/a_flaky_crash.cpp

@@ -14,7 +14,7 @@ bool bar(S);
 void foo() {
   int x;
   if (true && bar(S()))
-    ++x; // expected-warning{{The expression is an uninitialized value. The computed value will also be garbage}}
+    ++x; // expected-warning{{The expression uses uninitialized memory}}
 }
 
 // 256 copies of the same run-line to make it crash more often when it breaks.

clang/test/Analysis/analysis-after-multiple-dtors.cpp

@@ -23,6 +23,6 @@ int main() {
 
   int x;
   int y = x;
-  // expected-warning@-1{{Assigned value is garbage or undefined}}
+  // expected-warning@-1{{Assigned value is uninitialized}}
   (void)y;
 }

clang/test/Analysis/array-init-loop.cpp

@@ -19,7 +19,7 @@ void array_uninit() {
 
   auto [a, b, c, d, e] = arr;
 
-  int x = e; // expected-warning{{Assigned value is garbage or undefined}}
+  int x = e; // expected-warning{{Assigned value is uninitialized}}
 }
 
 void lambda_init() {
@@ -168,7 +168,7 @@ struct S3_duplicate {
 void array_uninit_non_pod() {
   S3 arr[1];
 
-  auto [a] = arr; // expected-warning@159{{ in implicit constructor is garbage or undefined }}
+  auto [a] = arr; // expected-warning@159{{ in implicit constructor is uninitialized}}
 }
 
 void lambda_init_non_pod() {
@@ -191,7 +191,7 @@ void lambda_init_non_pod() {
 void lambda_uninit_non_pod() {
   S3_duplicate arr[4];
 
-  int l = [arr] { return arr[3].i; }(); // expected-warning@164{{ in implicit constructor is garbage or undefined }}
+  int l = [arr] { return arr[3].i; }(); // expected-warning@164{{ in implicit constructor is uninitialized }}
 }
 
 // If this struct is being copy/move constructed by the implicit ctors, ArrayInitLoopExpr