The analyzer detected a potential error in the program: coincidence of two actual arguments of a function. Passing the same value as two arguments is a normal thing for many functions. But if you deal with such functions as memmove, memcpy, strstr and strncmp, you must check the code.
Here is a sample from a real application:
#define str_cmp(s1, s2) wcscmp(s1, s2) ... v = abs(str_cmp(a->tdata, a->tdata));
The misprint here causes the wcscmp function to perform comparison of a string from itself. This is the correct code:
v = abs(str_cmp(a->tdata, b->tdata));
The analyzer generates the warning if the following functions are being handled: memcpy, memmove, memcmp, _memicmp, strstr, strspn, strtok, strcmp, strncmp, wcscmp, _stricmp, wcsncmp, etc. If you found a similar error that analyzer fails to diagnose, please tell us the name of the function that must not take same values as the first and second arguments.