[temp.dep.constexpr]

An id-expression is value-dependent if

(2.1)
it is a concept-id and its concept-name is dependent or any of its arguments are dependent ([temp.dep.temp]),
(2.2)
it is type-dependent,
(2.3)
it is the name of a constant template parameter,
(2.4)
it is a name introduced by the for-range-declaration of an expansion-statement ([stmt.expand]),
(2.5)
it names a static data member that is a dependent member of the current instantiation and is not initialized in a member-declarator,
(2.6)
it names a static member function that is a dependent member of the current instantiation, or
(2.7)
it names a potentially-constant variable ([expr.const]) that is initialized with an expression that is value-dependent.

Expressions of the following form are value-dependent if the unary-expression or expression is type-dependent or the type-id is dependent:

sizeof unary-expression
sizeof ( type-id )
typeid ( expression )
typeid ( type-id )
alignof ( type-id )

[Note 1:

For the standard library macro offsetof, see [support.types].

— end note]

Expressions of the following form are value-dependent if either the type-id, simple-type-specifier, or typename-specifier is dependent or the expression or cast-expression is value-dependent or any expression in the expression-list is value-dependent or any assignment-expression in the braced-init-list is value-dependent:

simple-type-specifier ( expression-list

{o p t) typename-specifier (expression-list {o p t) simple-type-specifier braced-init-list typename-specifier braced-init-list static_cast < type-id > (expression) const_cast < type-id > (expression) reinterpret_cast < type-id > (expression) dynamic_cast < type-id > (expression) (type-id) cast-expression}_{o p t) simple-type-specifier braced-init-list typename-specifier braced-init-list static_cast < type-id > (expression) const_cast < type-id > (expression) reinterpret_cast < type-id > (expression) dynamic_cast < type-id > (expression) (type-id) cast-expression}}_{o p t) typename-specifier (expression-list {o p t) simple-type-specifier braced-init-list typename-specifier braced-init-list static_cast < type-id > (expression) const_cast < type-id > (expression) reinterpret_cast < type-id > (expression) dynamic_cast < type-id > (expression) (type-id) cast-expression}_{o p t) simple-type-specifier braced-init-list typename-specifier braced-init-list static_cast < type-id > (expression) const_cast < type-id > (expression) reinterpret_cast < type-id > (expression) dynamic_cast < type-id > (expression) (type-id) cast-expression}}

Expressions of the following form are value-dependent:

sizeof .. ( identifier )
fold-expression

A noexcept-expression ([expr.unary.noexcept]) is value-dependent if its expression involves a template parameter.

An expression of the form &qualified-id where the qualified-id names a dependent member of the current instantiation is value-dependent.

An expression of the form &cast-expression is also value-dependent if evaluating cast-expression as a core constant expression succeeds and the result of the evaluation refers to a templated entity that is an object with static or thread storage duration or a member function.

A reflect-expression is value-dependent if

(7.1)
it is of the form ^^reflection-name and the reflection-name
- (7.1.1)
  is a dependent qualified name,
- (7.1.2)
  is a dependent namespace-name,
- (7.1.3)
  is the name of a template parameter, or
- (7.1.4)
  names a dependent member of the current instantiation ([temp.dep.type]),
(7.2)
it is of the form ^^type-id and the type-id denotes a dependent type, or
(7.3)
it is of the form ^^id-expression and the id-expression is value-dependent.

A splice-expression is value-dependent if its splice-specifier or splice-specialization-specifier is dependent ([temp.dep.splice]).