c++ - Conditional weak-linked symbol modification/redeclaration -

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i have following weakly linked declaration:

extern __attribute__((visibility ("default"))) type* const symbolname __attribute__((weak_import));

the problem is, symbol may or may not defined, depending on operating system.

so, when use func(symbolname);, signal 11 crash because attempting dereference of null. ask if(&symbolname != null) { func(symbolname); }, require using symbol remember asking question, not optimal.

i looking wizardly magic conditionally modify or redeclare symbol, if unavailable, have default value func work with.

i understand ugly solution , not recommended. @ point, want know if there way it, no matter how ugly or low-level.


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