[clang-tools-extra] r286010 - [ClangTidy - performance-unnecessary-value-param] Only add "const" when current parameter is not already const qualified

[Felix Berger via cfe-commits]

Author: flx
Date: Fri Nov  4 15:51:31 2016
New Revision: 286010

URL: http://llvm.org/viewvc/llvm-project?rev=286010&view=rev
Log:
[ClangTidy - performance-unnecessary-value-param] Only add "const" when current parameter is not already const qualified

Reviewers: alexfh, sbenza, aaron.ballman

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D26207

Modified:
    clang-tools-extra/trunk/clang-tidy/performance/UnnecessaryValueParamCheck.cpp
    clang-tools-extra/trunk/test/clang-tidy/performance-unnecessary-value-param.cpp

Modified: clang-tools-extra/trunk/clang-tidy/performance/UnnecessaryValueParamCheck.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/performance/UnnecessaryValueParamCheck.cpp?rev=286010&r1=286009&r2=286010&view=diff
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/performance/UnnecessaryValueParamCheck.cpp (original)
+++ clang-tools-extra/trunk/clang-tidy/performance/UnnecessaryValueParamCheck.cpp Fri Nov  4 15:51:31 2016
@@ -128,7 +128,10 @@ void UnnecessaryValueParamCheck::check(c
     const auto &CurrentParam = *FunctionDecl->getParamDecl(Index);
     Diag << utils::fixit::changeVarDeclToReference(CurrentParam,
                                                            *Result.Context);
-    if (!IsConstQualified)
+    // The parameter of each declaration needs to be checked individually as to
+    // whether it is const or not as constness can differ between definition and
+    // declaration.
+    if (!CurrentParam.getType().getCanonicalType().isConstQualified())
       Diag << utils::fixit::changeVarDeclToConst(CurrentParam);
   }
 }

Modified: clang-tools-extra/trunk/test/clang-tidy/performance-unnecessary-value-param.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/test/clang-tidy/performance-unnecessary-value-param.cpp?rev=286010&r1=286009&r2=286010&view=diff
==============================================================================
--- clang-tools-extra/trunk/test/clang-tidy/performance-unnecessary-value-param.cpp (original)
+++ clang-tools-extra/trunk/test/clang-tidy/performance-unnecessary-value-param.cpp Fri Nov  4 15:51:31 2016
@@ -244,3 +244,19 @@ struct IncompleteType;
 void NegativeForIncompleteType(IncompleteType I) {
   // CHECK-MESSAGES: [[@LINE-1]]:47: error: variable has incomplete type 'IncompleteType' [clang-diagnostic-error]
 }
+
+// Case where parameter in declaration is already const-qualified but not in
+// implementation. Make sure a second 'const' is not added to the declaration.
+void PositiveConstDeclaration(const ExpensiveToCopyType A);
+// CHECK-FIXES: void PositiveConstDeclaration(const ExpensiveToCopyType& A);
+void PositiveConstDeclaration(ExpensiveToCopyType A) {
+  // CHECK-MESSAGES: [[@LINE-1]]:51: warning: the parameter 'A' is copied
+  // CHECK-FIXES: void PositiveConstDeclaration(const ExpensiveToCopyType& A) {
+}
+
+void PositiveNonConstDeclaration(ExpensiveToCopyType A);
+// CHECK-FIXES: void PositiveNonConstDeclaration(const ExpensiveToCopyType& A);
+void PositiveNonConstDeclaration(const ExpensiveToCopyType A) {
+  // CHECK-MESSAGES: [[@LINE-1]]:60: warning: the const qualified parameter 'A'
+  // CHECK-FIXES: void PositiveNonConstDeclaration(const ExpensiveToCopyType& A) {
+}