From 0bb43854c7cb77d25d0ee33ed4263659a031dac7 Mon Sep 17 00:00:00 2001 From: Peter Todd Date: Wed, 27 May 2015 21:02:04 -0400 Subject: Improve comment explaining purpose of MAX_MONEY constant --- src/amount.h | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/src/amount.h b/src/amount.h index 9212244a88..7dc62edac4 100644 --- a/src/amount.h +++ b/src/amount.h @@ -16,7 +16,15 @@ typedef int64_t CAmount; static const CAmount COIN = 100000000; static const CAmount CENT = 1000000; -/** No amount larger than this (in satoshi) is valid */ +/** No amount larger than this (in satoshi) is valid. + * + * Note that this constant is *not* the total money supply, which in Bitcoin + * currently happens to be less than 21,000,000 BTC for various reasons, but + * rather a sanity check. As this sanity check is used by consensus-critical + * validation code, the exact value of the MAX_MONEY constant is consensus + * critical; in unusual circumstances like a(nother) overflow bug that allowed + * for the creation of coins out of thin air modification could lead to a fork. + * */ static const CAmount MAX_MONEY = 21000000 * COIN; inline bool MoneyRange(const CAmount& nValue) { return (nValue >= 0 && nValue <= MAX_MONEY); } -- cgit v1.2.3