Failed to find or create execution context for description <IBCocoaTouchPlatformToolDescription: 0x7fa8bad9a6f0>

Solution 1:

Restarting the CoreSimulatorService solved the issue on my machine.

sudo killall -9 com.apple.CoreSimulator.CoreSimulatorService

Solution 2:

I had the same problem after I upgrade my Xcode to version 10.3.

I just restart my Mac and problem solved!

Hope this would work with you too :)

Solution 3:

Mine happened when updating to Xcode 10.3

X-code helper didn't get the permission to control the computer.

This is what i did to solve the problem

System Preference > Security&Privacy > privacy tab > accessibility

give permission for 'Xcode Helper'

Restart X-code and kill all simulators like @riik stated

sudo killall -9 com.apple.CoreSimulator.CoreSimulatorService

Solution 4:

This issue is with xcode update 10.3 and mixpannel is gives this as build error

Steps to fix.

Open terminal and paste this

sudo killall -9 com.apple.CoreSimulator.CoreSimulatorService

Clean Xcode and build. Thats all