[Bug libstdc++/123480] -static-libstdc++ exposes libstdc++ symbols in executable on RISC-V/MIPS, but not on x86

[uwu at icenowy dot me via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123480

--- Comment #29 from Icenowy Zheng <uwu at icenowy dot me> ---
```
icenowy@edelgard [ tmp ] $ cat test.cpp
#include <iostream>

int main()
{
        std::cout << "a" << std::endl;
}

icenowy@edelgard [ tmp ] $ g++ test.cpp -static-libstdc++
icenowy@edelgard [ tmp ] $ nm -D a.out | grep cxx
icenowy@edelgard [ tmp ] $ nm -D a.out | grep cxx | wc -l
0
```

Another reference on x86-64, which shows no symbols of libstdc++ are exported
by the executable here.