Bad CPU Type In Executable Homebrew | How To Fix the Error

Homebrew is a popular package manager for macOS and Linux, allowing users to install and manage software packages effortlessly. However, as with any software, Homebrew can sometimes run into issues, including the dreaded “Bad CPU type in executable” error.

To fix “Bad CPU Type In Executable” with Homebrew, update Homebrew and its packages, ensure Compatibility with your macOS version, and consider Rosetta on M1 Macs for Intel-based applications.

In this guide, we will explore the causes of this error and provide a step-by-step solution to resolve it, focusing on installing Homebrew on your Apple Silicon Mac.

Understanding The Error “Bad CPU Type In Executable.”

The “Bad CPU type in executable” error occurs when you attempt to run a program or script compiled for an architecture different from your Mac’s.

In the context of M1 and M2 Macs, this error is typically caused by trying to run software designed for Intel-based Macs.

Apple’s transition to ARM64 architecture with their M1 and M2 chips means that Intel-based software needs proper translation.

Source: medium

Causes Of The Error “Bad CPU Type In Executable.”:

There are two primary causes of the “Bad CPU type in executable” error on M1 and M2 Macs:

1. Incompatible Software: 

The error often arises when running 32-bit Intel software on ARM64-based Apple Silicon Macs. macOS Catalina and later versions no longer support 32-bit applications.

2. Missing Rosetta 2: 

Rosetta 2 is Apple’s translation layer that allows Intel-based software to run on Apple Silicon Macs. If Rosetta 2 is not installed on your Mac, you will encounter this error when running Intel-based software.

3. Outdated Software: 

One of the most common causes of this error is using outdated software. If you still need to update Homebrew or the software package in question, it may not be compatible with your macOS version or CPU architecture.

4. 32-bit vs. 64-bit: 

macOS has transitioned from 32-bit to 64-bit architecture, with newer macOS versions exclusively supporting 64-bit applications. You’ll encounter this error if you attempt to run a 32-bit binary on a modern macOS.

5. Cross-Compilation Issues: 

Some software packages are cross-compiled to run on multiple CPU architectures. If the cross-compilation process isn’t handled correctly, it could create a binary incompatible with your system.

6. Custom Taps And Repositories: 

Homebrew allows users to create custom “taps” or repositories for software packages. You may face this error if a tap contains a binary that doesn’t align with your CPU architecture.

How To Fix the Error “Bad CPU Type In Executable.”: Step By Step Guide:

How To Fix the Error "Bad CPU Type In Executable
Source: reddit

To resolve the “Bad CPU type in executable” error and install Homebrew on your M1 or M2 Mac, follow these steps:

Open Terminal: 

Launch Terminal on your Mac. You can find it in the “Utilities” folder within the “Applications” folder or by using Spotlight search.

Install Rosetta 2: 

To ensure Compatibility with Intel-based software, you need to install Rosetta 2. Enter the following command in Terminal:

/usr/sbin/softwareupdate –install-rosetta –agree-to-license

Press Enter, and Rosetta 2 will be installed on your Mac. Wait for the installation to complete.

Install Homebrew: 

Once Rosetta 2 is installed, you can proceed to install Homebrew. Use the following command:

/bin/bash -c “$(curl -fsSL”

This command will download and install Homebrew on your Mac. It should work without triggering the “Bad CPU type in executable” error.

Verify Installation: 

After Homebrew is installed, you can verify its installation by running the following command:

brew –version

This should display the installed Homebrew version.

Alternative Methods To Fix The Error “Bad CPU Type In Executable.”

If the upper steps were not working, consider applying the following methods to resolve bad CPU Type in Executable error.

Update Homebrew: 

Update Homebrew
Source: github

Keeping your Homebrew installation and packages up to date is crucial. Run the following commands to ensure everything is current:

brew update

brew upgrade

Check macOS Version: 

Verify that your macOS version is compatible with the software package you are trying to install or run. Some packages may not work on older or newer macOS releases.

64-bit Compatibility:

If you use a 64-bit macOS version, but the software you’re trying to run is 32-bit, consider finding an alternative or contacting the package maintainers for an updated version.


 If you suspect that the software package was not compiled correctly, try uninstalling and reinstalling it, following any special installation instructions provided by the maintainers.

Review Homebrew Taps: 

If you use custom taps or repositories, ensure the software they contain is compatible with your CPU architecture and macOS version. If not, consider removing or replacing problematic taps.

Consider Rosetta: 

On M1 Macs, you can use Apple’s Rosetta technology to run Intel-based applications. To run an application using Rosetta, use the following command:

arch -x86_64 /path/to/executable

Troubleshooting The “Bad CPU Type In Executable” Error On macOS:

The “bad CPU type in executable” error on macOS can hinder using the Arduino development software. Below, we outline steps to resolve the error based on your Mac’s processor type.

If your Mac has an Apple Silicon processor (like M1 or M2), installing Rosetta is essential. This compatibility layer allows Intel-based software to run on Apple Silicon Macs. Here’s how to do it:

Installation Dialog (Recommended):

Installation Dialog (Recommended):
Source: docs.revenera

When you start an application that requires Rosetta, macOS should prompt you to install it. If you encounter this dialog while launching the Arduino development software, follow these steps:

  • Click the “Install” button.
  • Complete the installation process as guided by macOS.

Manual Installation (If Required):

If the Arduino software runs a tool as a subprocess and doesn’t trigger the installation dialog, you’ll need to install Rosetta manually. Here’s how:

  • Open Terminal on your Mac (you can find it in the Utilities folder within Applications or use Spotlight search).
  • In the Terminal window, enter the following command:

softwareupdate –install-rosetta

  • Press the Enter key.
  • Accept the license agreement presented by Apple.
  • Wait for the installation process to complete.

For Macs With Different Processors Or Existing Rosetta Installation:

If your Mac has a different processor or Rosetta is already installed but still encounters the “bad CPU type in executable” error, it may be due to outdated tools or platform versions. Follow these steps to address this issue:

Update the Platform for Your Board:

  • Open the Arduino IDE on your Mac.
  • Navigate to “Tools”> “Board”> “Boards Manager…” in the Arduino IDE menus.
  • In the “Boards Manager” view, scroll through the list of board platforms until you find the one corresponding to your board.
  • Check if a newer version is listed at the bottom of the entry.
  • If a newer version is available, click the “INSTALL” button at the bottom of the entry.
  • Wait for the update to finish.
  • Close the “Boards Manager” view.

Following these steps, you can resolve the “bad CPU type in executable” error and ensure that the Arduino development software runs smoothly on your Mac, regardless of its processor architecture.

Frequently Asked Questions:

1. Should You Install Homebrew As Root?

According to the error message, you are running Homebrew as root is extremely risky and no longer supported.

You would grant all build scripts complete access to your machine because Homebrew does not revoke privileges upon installation. Nothing I did worked, including sudo chown -R $(whoami) $(brew –prefix)/*.

2. Is It Illegal To Install Homebrew?

Running your programs on that console is legal. Sharing and “making available” ROMs are prohibited activities. People who say, “You wouldn’t download a car,” are missing the fact that publishing content violates copyright, not downloading it.

3. Is Rosetta Pre-Installed On macOS, Or Must I Install It Separately?

On macOS, Rosetta still needs to be installed. If your Mac prompts you to install a program that needs Rosetta, do so. Then, proceed as directed. If not, you can use Terminal to install Rosetta manually.

4. What Is The Purpose Of Rosetta On Apple Silicon Macs?

Rosetta is a compatibility layer that makes it simple for Apple Silicon Macs to run programs with an Intel architecture. The instructions are translated, enabling software created for Intel CPUs to run on Apple Silicon Macs.


The “Bad CPU type in executable” error can be a roadblock when running incompatible software on M1 and M2 Macs.

However, by installing Rosetta 2 and then proceeding with Homebrew installation, you can overcome this issue and enjoy the benefits of easy software management on your Apple Silicon Mac.

This guide provides a straightforward solution to help you start with Homebrew and other software on your M1 or M2 Mac without encountering compatibility errors.