Disable clang-tidy readability checkers when not compiling in C++ mode. None of the checkers require additional testing as the tests will not compile for other languages or modes, or the checkers would never match a valid construct.

llvm-svn: 246661

clang-tools-extra/clang-tidy/readability/ContainerSizeEmptyCheck.cpp

@@ -54,6 +54,11 @@ ContainerSizeEmptyCheck::ContainerSizeEmptyCheck(StringRef Name,
     : ClangTidyCheck(Name, Context) {}
 
 void ContainerSizeEmptyCheck::registerMatchers(MatchFinder *Finder) {
+  // Only register the matchers for C++; the functionality currently does not
+  // provide any benefit to other languages, despite being benign.
+  if (!getLangOpts().CPlusPlus)
+    return;
+
   const auto WrongUse = anyOf(
       hasParent(
           binaryOperator(

clang-tools-extra/clang-tidy/readability/NamespaceCommentCheck.cpp

@@ -34,7 +34,10 @@ void NamespaceCommentCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
 }
 
 void NamespaceCommentCheck::registerMatchers(MatchFinder *Finder) {
-  Finder->addMatcher(namespaceDecl().bind("namespace"), this);
+  // Only register the matchers for C++; the functionality currently does not
+  // provide any benefit to other languages, despite being benign.
+  if (getLangOpts().CPlusPlus)
+    Finder->addMatcher(namespaceDecl().bind("namespace"), this);
 }
 
 static bool locationsInSameFile(const SourceManager &Sources,

clang-tools-extra/clang-tidy/readability/RedundantSmartptrGetCheck.cpp

@@ -74,6 +74,11 @@ void registerMatchersForGetEquals(MatchFinder *Finder,
 }  // namespace
 
 void RedundantSmartptrGetCheck::registerMatchers(MatchFinder *Finder) {
+  // Only register the matchers for C++; the functionality currently does not
+  // provide any benefit to other languages, despite being benign.
+  if (!getLangOpts().CPlusPlus)
+    return;
+
   registerMatchersForGetArrowStart(Finder, this);
   registerMatchersForGetEquals(Finder, this);
 }

clang-tools-extra/clang-tidy/readability/RedundantStringCStrCheck.cpp

@@ -80,6 +80,11 @@ namespace readability {
 
 void RedundantStringCStrCheck::registerMatchers(
     ast_matchers::MatchFinder *Finder) {
+  // Only register the matchers for C++; the functionality currently does not
+  // provide any benefit to other languages, despite being benign.
+  if (!getLangOpts().CPlusPlus)
+    return;
+
   Finder->addMatcher(
       constructExpr(
           hasDeclaration(methodDecl(hasName(StringConstructor))),