If I use msg.gas
statement inside my contract, does executing that line itself need gas? If yes, how much does it need?
2 Answers
Please note that msg.gas
is deprecated. You should use gasleft()
if you are over version 0.4.21
.
The function itself uses the gas
opcode which is in the base group and thus costs 2 gas.
msg.gas
was renamed to gasleft()
.
Anyway, everything has a cost, for gasleft()
it is defined here. The associated cost is GasQuickStep
which is set to 2.
It therefore cost you 2 gas to know how much gas is left.