The weak variable attribute

The weak variable attribute causes the symbol resulting from the variable 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 variable definitions in user code to override the library declaration without causing duplicate name errors.

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

Related information

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