MSAN: getentropy() is unsupported

[guidovranken]

MSAN will detect uninitialized memory after a call to

int getentropy(void *buffer, size_t length);

Example program:

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
int main(void)
{
    unsigned char x[128];
    if ( getentropy(x, 128) == -1 ) abort();

    /* Branch on x[0] */
    if ( x[0] == 0 ) {
        return 10;
    }
    return 0;
}