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__attribute__((weakref("target"))) variable attribute

This variable attribute marks a variable declaration as an alias that does not by itself require a definition to be given for the target symbol.



Where target is the target symbol.


In the following example, a is assigned the value of y through a weak reference:

extern int y;
static int x __attribute__((weakref("y")));
void foo (void)
  int a = x;


This attribute can only be used on variables that are declared as static.