I found that function gen_salt() in contrib/pgcrypto had bug on win32.
I patched contrib/pgcrypto/random.c file.
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$ diff random.orig.c random.c
42a43
> #include <time.h>
87a89,90
> srandom(time(NULL));
>
89c92
< *dst++ = random();
---
> dst[i] = (random() % 255);
plz, check and apply.