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- Print C++ vtables using GDB 5 answers
How to display vtable using a pointer to base class object having virtual functions?
Did you try set print object on ?
(gdb) help set print object
Set printing of object's derived type based on vtable info.
If you have a sufficiently new version of gdb, you may want to look at the "info vtbl" command (or perhaps it is called "info vtable"; my own version of gdb is not sufficiently new, and so I cannot test the feature out myself).
I only noticed the feature when googling for an answer to this question and I noticed posts to the gdb mailing list circa 2012, notably this one from March 2012:
来源：https://stackoverflow.com/questions/2529561/vtable-in-polymorphic-class-of-c-using-gdb