> For the complete documentation index, see [llms.txt](https://docs.hex-rays.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.hex-rays.com/ida-actions/makefunction.md).

# MakeFunction

## Description

Create a new function in the disassembly. You can specify function boundaries using the anchor. If you don't specify any, IDA will try to find the boundaries automatically:

* function start point is equal to the current cursor position;
* function end point is calculated by IDA.

A function cannot contain references to undefined instructions. If a function has already been defined at the specified addresses, IDA will jump to its start address, showing you a warning message. A function must start with an instruction.


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