C++ Standards Compliance

CLion incorporates two language engines: the built-in one and the Clangd-based one.

The Clangd-based engine detects warnings and errors to be shown in the editor, performs certain navigation actions, highlighting and quick-fixes, while other code insight features (like refactorings and completion) are provided by the CLion's own code engine. For details, see the Clangd reference page.

The built-in language engine in CLion supports the C++ standards up to C++14 and partially C++17. Tables below show the lists of each standard's features marked as supported , currently supported only in parsing , or unsupported in CLion.

C++17

Feature	Status
Nested namespace definition
fold expressions
class template argument deduction
auto non-type parameters
UTF-8 character literals
__has_include
Lambda capture of *this
[[nodiscard]] attribute
[[fallthrough]] attribute
[[maybe_unused]] attribute
Made noexcept as a part of the function type
One-argument static assert
if constexpr
Initializers in if and switch statements
Inline variables
New rules for auto deduction from braced-init-list
constexpr lambdas
Structured binding declaration

C++14

Feature	Status
Variable templates
Generic lambdas
Binary literals
Aggregate initialization for classes with brace-or-equal initializers
[[deprecated]] attribute
Single quote as digit separator
Return type deduction for normal functions
Generalized lambda capture
constexpr specifier

C++11

Feature	Status
auto specifier
decltype specifier
final specifier
override specifier
Trailing return initialization
rvalue references
Variadic templates
List initialization
In-class member initializers
Delegating constructors
Inheriting constructors
nullptr
long long
char16_t and char32_t
Generalized unions
Generalized POD's
thread_local storage
GC interface
range for
Static asserts
Explicit specifier
default/ delete keywords
Scoped enum
thread_local keyword
noexcept specifier
noexcept operator
Inline namespaces
alignof / alignas specifiers
extern template
attribute specifier sequence
Lambda functions
Raw string literals
Type aliases
Type traits
User-defined literals
constexpr specifier