std::locale [con/de]structor undefined

```C++
#include
void setup() {
std::locale L;
}

void loop() {
}
```
```
C:\Users\vhtmf\AppData\Local\Temp\arduino\sketches\52F23F0CFDD118EC78D3909BB8E326BF\sketch\Functional.ino.cpp.o: In function `setup':
C:\Users\vhtmf\Documents\Arduino\libraries\Cpp_Standard_Library\examples\Functional/Functional.ino:3: undefined reference to `std::locale::locale()'
C:\Users\vhtmf\Documents\Arduino\libraries\Cpp_Standard_Library\examples\Functional/Functional.ino:3: undefined reference to `std::locale::~locale()'
collect2.exe: error: ld returned 1 exit status

exit status 1

Compilation error: exit status 1
```

Reproduce the minimal Arduino sketch that includes and constructs std::locale, using the Functional example and the linker output as the starting points. Trace the Arduino SAM build and linking behavior for std::locale; done means the example no longer reports undefined constructor and destructor references, or the supported limitation is clearly established.

Written by the indexing model from the issue text.