Where is this capture stored in this C# Lambda? -

this question has answer here:

• how closure in c# works when using lambda expressions? 3 answers
• how closures work behind scenes? (c#) 3 answers

all of posts c# lambdas says captures references variables.

but how can this?

private system.action lambda; void start()  {     int = 0;     lambda = () => {         i++;         debug.log(i);      }; } void update() {     lambda(); } 

this print out 1..2...3...etc

my understanding variable allocated on stack, referenced. after start() exits, should destroyed, causing undefined behavior when lambda() called.