Why the literal "-9223372036854775808" (min 64 bit signed integer) is not accepted by kotlin?

Question

I'm trying to write a fast json parser for JVM in kotlin.

And I found this issue, I'm not sure this is a bug or any good reason behind this.

val x: Long = -9223372036854775808L  // compile error

And `-9223372036854775807L` is accepted, interesting... Btw, it would be helpful if the exact message was provided. — zerkms, Jun 25 '17 at 05:13

score 4 · Accepted Answer · answered Jun 25 '17 at 05:13

this is marked as a bug in kotlin KT-17172.

as you can see the stdlib using the code as below:

public const val MIN_VALUE: Long = -9223372036854775807L - 1L

are you remember unary operator - in kotlin? if you divide the MIN_VALUE into special parts you may see it clearly. for example:

val x: Long = -(9223372036854775808L);
//              ^--- the value overflow since the MAX_VALUE is 9223372036854775807L

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