A type attribute is a declaration specifier that uses the keyword
__attribute__ and its accompanying syntax to specify special
properties for a structure, union, enumeration, or class. Type
attributes are orthogonal extensions to C and C++, implemented to facilitate
porting programs developed with GNU C and C++.
The syntax of a type attribute is of the general form:
>>-__attribute__--((--+-attribute_name-----+--))--------------->< '-__attribute_name__-'
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