os::print_memory_mappings() is a helpful little routine to print existing memory mappings within a given range. On Linux, it parses proc/<pid>/maps. But it always prints a segment preceding the start address, e.g. here see the first line:

```
Range [7f92467a3000-7f92467a9000) contains: 7f924679f000-7f92467a3000 rw-p 00000000 00:00 0
7f92467a3000-7f92467a4000 rwxp 00000000 00:00 0
7f92467a4000-7f92467a5000 rw-p 00000000 00:00 0
7f92467a5000-7f92467a6000 rwxp 00000000 00:00 0
7f92467a6000-7f92467a7000 rw-p 00000000 00:00 0
7f92467a7000-7f92467a8000 rwxp 00000000 00:00 0
7f92467a8000-7f92467a9000 rw-p 00000000 00:00 0
```

and it should also precede the first line with a newline