The weak function attribute

The weak function attribute causes the symbol resulting from the function declaration to appear in the object file as a weak symbol, rather than a global one. The language feature provides the programmer writing library functions with a way to allow function definitions in user code to override the library function declaration without causing duplicate name errors.

Read syntax diagramSkip visual syntax diagramweak function attribute syntax
 
>>-__attribute__--((--+-weak-----+--))-------------------------><
                      '-__weak__-'
 

Related information

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