For debugging purposes I have enabled, from menu "Target Options", enable "Mask interrupts during step". In general, how will the CLI behave when I keep the breakpoint at this instruction with the above mentioned option enabled?
The "Mask interrupts during step" option modifies the interrupt mask registers, so you should be aware that stepping through code which itself modifies these registers, such as a CLI or STI, could be problematic, as changes to the the registers may be lost. Also note that when this option is used, the interrupt is masked, so no ISR code will be called during the stepping process.
This FAQ was generated from the following thread: CLI and "Target option Mask interrupts during step"