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In this noncompliant code example, the variable v is defined in an unnamed namespace within a header file, and an inline function, get_v(), is defined, which accesses that variable. ODR-using Using the inline function from multiple translation units (as shown in the implementation of f() and g()) violates the one-definition rule because the definition of get_v() is not identical in all translation units (due to referencing a unique v in each translation unit).
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