[Solved][ASM][1.7.2] How did I go wrong?

[williewillus]

Hiya,

I'm starting to feel my way around ASM and bytecode manipulation, and decided to create a fix for one my most annoying bugs of all time, https://bugs.mojang.com/browse/MC-29475.

I know what base edit I need to do, I need to change Line ~382 of EntityArrow, in its onUpdate() method, from

 

this.field_145790_g = var16;

 

to

 

this.field_145790_g = this.worldObj.getBlock(this.field_145791_d, this.field_145791_e, this.field_145791_f);

 

In a MCP environment, this fixes the bug completely with no side effects observed.

 

Here is my effort so far using ASM coremodding: https://github.com/williewillus/ArrowFix

 

I know for sure that my instructions are injected into the correct place in the method successfully;

the game starts and runs.

However, the game crashes when I fire an arrow, with this error: http://pastebin.com/5sZFV44f

Which tells me that I may have formatted my instruction injections wrongly or used the incorrect instruction altogether.

 

Any pointers on where I went wrong, how I can improve?

[Chibill]

I beleave its because it to be somehow passing ()V to what it expects to be a int

 

or it seems to be a problem with how it was added.

 

I have not messed with ASM but I want too so yeah it ecpexting an int on the stack.

[williewillus]

It's just telling me that onUpdate()'s descriptor is ()V

 

My gut says that the ints it can't find refer to the invocation of getBlock() that I added, which means that I may have retrieved them from the fields the incorrect way. Can someone more experienced verify?

[williewillus]

That was it, I derped hard there

Thank you!