Major New Features¶

• clang-include-fixer, a tool that provides an automated way of adding #include directives for missing symbols in one translation unit.

  It aims to provide automated insertion of missing #includes with a single button press in an editor. Integration with Vim and a tool to generate the symbol index used by the tool are also part of this release. See the include-fixer documentation for more information.

Improvements to clang-tidy¶

clang-tidy‘s checks are constantly being improved to catch more issues, explain them more clearly, and provide more accurate fix-its for the issues identified. The improvements since the 3.8 release include:

• New Boost module containing checks for issues with Boost library.

• New boost-use-to-string check

  Finds usages of boost::lexical_cast<std::string> and changes it to std::to_string.

• New cert-env33-c check

  Flags calls to system(), popen(), and _popen(), which execute a command processor.

• New cert-err34-c check

  Flags calls to string-to-number conversion functions that do not verify the validity of the conversion.

• New cert-flp30-c check

  Flags for loops where the induction expression has a floating-point type.

• New cppcoreguidelines-interfaces-global-init check

  Flags initializers of globals that access extern objects, and therefore can lead to order-of-initialization problems.

• New cppcoreguidelines-pro-type-member-init check

  Flags user-defined constructor definitions that do not initialize all builtin and pointer fields which leaves their memory in an undefined state.

• New google-default-arguments check

  Flags default arguments in virtual methods.

• New misc-dangling-handle check

  Detects dangling references in value handlers like std::experimental::string_view.

• New misc-fold-init-type check

  The check flags type mismatches in folds like std::accumulate that might result in loss of precision.

• New misc-forward-declaration-namespace check

  Checks if an unused forward declaration is in a wrong namespace.

• New misc-misplaced-const check

  Checks if a const qualifier is applied to a typedef to pointer type instead of the underlying pointee type.

• New misc-misplaced-widening-cast check

  Warns when there is a explicit redundant cast of a calculation result to a bigger type.

• New misc-multiple-statement-macro check

  Detect multiple statement macros that are used in unbraced conditionals.

• New misc-pointer-and-integral-operation check

  Warns about suspicious operations involving pointers and integral types.

• New misc-redundant-expression check

  Warns about redundant and equivalent expressions.

• New misc-sizeof-expression check

  Warns about incorrect uses of sizeof operator.

• New misc-string-constructor check

  Finds string constructors that are suspicious and probably errors.

• New misc-string-literal-with-embedded-nul check

  Warns about suspicious NUL character in string literals which may lead to truncation or invalid character escaping.

• New misc-suspicious-missing-comma check

  Warns about ‘probably’ missing comma in string literals initializer list.

• New misc-suspicious-semicolon check

  Finds most instances of stray semicolons that unexpectedly alter the meaning of the code.

• New misc-suspicious-string-compare check

  Find suspicious usage of runtime string comparison functions.

• New misc-unconventional-assign-operator check replacing the misc-assign-operator-signature check.

  Does not only checks for correct signature but also for correct return statements (returning *this)

• New misc-unused-using-decls check

  Finds unused using declarations.

• New modernize-avoid-bind check

  Finds uses of std::bind and replaces simple uses with lambdas.

• New modernize-deprecated-headers check

  Replaces C standard library headers with their C++ alternatives.

• New modernize-make-shared check

  Replaces creation of std::shared_ptr from new expression with call to std::make_shared.

• New modernize-raw-string-literal check

  Selectively replaces string literals containing escaped characters with raw string literals.

• New modernize-use-bool-literals check

  Finds integer literals which are cast to bool.

• New modernize-use-emplace check

  Finds calls that could be changed to emplace.

• New modernize-use-using check

  Finds typedefs and replaces it with usings.

• New performance-faster-string-find check

  Optimize calls to std::string::find() and friends when the needle passed is a single character string literal.

• New performance-implicit-cast-in-loop check

  Warns about range-based loop with a loop variable of const ref type where the type of the variable does not match the one returned by the iterator.

• New performance-unnecessary-value-param check

  Flags value parameter declarations of expensive to copy types that are copied for each invocation but it would suffice to pass them by const reference.

• New readability-avoid-const-params-in-decls check

  Warns about top-level const parameters in function declarations.

• New readability-deleted-default check

  Warns about defaulted constructors and assignment operators that are actually deleted.

• Updated readability-identifier-naming-check

  Added support for enforcing the case of macro statements.

• New readability-redundant-control-flow check

  Looks for procedures (functions returning no value) with return statements at the end of the function. Such return statements are redundant.

• New readability-redundant-string-init check

  Finds unnecessary string initializations.

• New readability-static-definition-in-anonymous-namespace check

  Finds static function and variable definitions in anonymous namespace.

Fixed bugs:

• Crash when running on compile database with relative source files paths.
• Crash when running with the -fdelayed-template-parsing flag.
• The modernize-use-override check: incorrect fix-its placement around __declspec and other attributes.