D461 - std::random_device is deterministic here, on purpose

assumed - 2026-09-01 (user-directed /loop: overnight oracle-free crunch)

_ZSt14_Random_devicev (std::_Random_device(), the entropy primitive behind std::random_device) was unimplemented and answered a placeholder the guest would have seeded a generator with. Implementing it raises a question a real C++ library does not have to ask: should it be non-deterministic, as the standard intends?

For this emulator, no. Every measurement it makes - FURTHER/same/BACK, a fault address, a call budget - depends on two runs of one build behaving identically, which is the whole reason the call budget replaced wall-clock timing (D181, D238). A physically-random random_device would put non-determinism back into exactly the layer those decisions removed it from. A guest reads this only to seed its own generator, so what it needs is a well-distributed 32-bit value, not an unpredictable one; a fixed-seed sequence gives it that and keeps the run reproducible.

So it is a splitmix64 sequence (Vigna, public domain) from a fixed seed, low 32 bits returned (result_type is unsigned int), advanced once per call so successive reads differ. Verified reproducible: PPSA21564 ran to exactly 500257 calls on two consecutive runs, the count unchanged from before the implementation - a real-entropy version would have made that vary.

Marked assumed, because that this symbol is the entropy value-provider (rather than, say, a constructor) is inferred from the mangled name and the guest's use, not confirmed against a header for this exact runtime. It is a strict improvement on the placeholder regardless: harmless if the guest ignores the value, correct if it seeds with it. The stance generalises - any future entropy or clock primitive (getrandom, gettimeofday) should be deterministic-by-default or carry a flag, never silently non-reproducible. It did not move PPSA21564's int 0x41 wall, which is caused elsewhere (the hardware-gated sceKernelGetGPI); this was stub reduction, not a crack.