Are C++11 thread_local variables automatically static?

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According to the C++ Standard

When thread_local is applied to a variable of block scope the
storage-class-specifier static is implied if it does not appear
explicitly

So it means that this definition

void f() {
    thread_local vector<int> V;
    V.clear();
    ... // use V as a temporary variable
}

is equivalent to

void f() {
    static thread_local vector<int> V;
    V.clear();
    ... // use V as a temporary variable
}

However, a static variable is not the same as a thread_local variable.

1 All variables declared with the thread_local keyword have thread
storage duration. The storage for these entities shall last for the
duration of the thread in which they are created. There is a distinct
object or reference per thread, and use of the declared name refers to
the entity associated with the current thread

To distinguish these variables the standard introduces a new term thread storage duration along with static storage duration.

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