What are cases where the MSVC c++ compiler option /volatile:ms and /volatile:iso show differences in the output assembler?

The following msvc command line option suggests that memory fences are introduced using the option /volatile:ms (default) but not when using /volatile:iso. I have not been able to come up with any example code that does this.

For example one of my random attempts

https://godbolt.org/z/qrz18j3h9

volatile int A, B;


void foo()
{
    A = B+1;
    B = A+1;
}

generates the following asm

int volatile A DD        01H DUP (?)                   ; A
int volatile B DD        01H DUP (?)                   ; B
voltbl  SEGMENT
_volmd  DB  00H
        DB      08H
        DB      0eH
        DB      016H
voltbl  ENDS

void foo(void) PROC                                        ; foo, COMDAT
        mov     eax, DWORD PTR int volatile B                    ; B
        inc     eax
        mov     DWORD PTR int volatile A, eax                    ; A
        mov     eax, DWORD PTR int volatile A                    ; A
        inc     eax
        mov     DWORD PTR int volatile B, eax                    ; B
        ret     0
void foo(void) ENDP  

irrespective of whether I use option /volatile:ms or /volatile:iso with Visual Studio 2019.

Can somebody provide an example where the above two options do make a difference to the output assembly code?