Wrong stack computation with (retained) dead code

[Rafael Winterhalter]

Hello,

this is tested with a recent 24 EA.

I discovered that some generated classes in Byte Buddy fail to verify with:
Operand stack overflow - Exceeded stack size. This seems to happen when
adding dead code, even if frames are created manually. For example, if I
use the class file API to create the following method, I'd create the above
verify error:

String m() {
  LDC "x"
  ARETURN
  F_SAME
  LDC "x"
  LDC "x"
  ARETURN
}

This code might appear meaningless, but there are a bunch of code
generators that create such weird code, that is why Byte Buddy supports it.
It seems like the class file API computes the required stack size at 1, not
as 2. Currently, I cannot override this.

If this class is picked up by a Java agent and simply passed and returned,
the max size will therefore decrease and the verification error will
surface.

Best regards, Rafael
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