Go to
C/C++ Build -> Settings -> Build Steps
Under the section
Post-build steps.
Change the text in the command field
${cross_prefix}${cross_objcopy}${cross_suffix} firmware.elf -O binary firmware.bin
To this: ${cross_prefix}objcopy${cross_suffix} firmware.elf -O binary firmware.bin
Then click on
Apply and Close
Now when you Build you won’t see that error