Why gdb inside emacs cannot print out c++ object?

[Kevin Gao]

Hello folks,

I hit an issue when debugging c++ code using gdb inside emacs.

Suppose: p is c++ iterator of an object of multimap<int, pair<string,
string>>;

inside emacs gdb (with many windows on), "p p" returns:
*$1 = {_M_node = 0x555555775fa0}*, which is meaningless to me.

As a comparison, in raw gdb (etc gdb ./a.out), "p p" returns:
*$1 = {first = 1, second = {first = "foo", second = "bar"}}*, which is what
I want to see.

Why gdb inside emacs cannot print out c++ object? Seems emacs does some
special setting which turns off c++ mode?

This is really a blocking issue for C++ debug. Please share you idea.

Thanks,