5.8.4 .err
If the assembler sees an .err directive, it will print an
error message, and unless the -Z option was used, it will not generate an
object file. This can be used to signal an error in conditionally compiled code.
If the assembler sees an .err directive, it will print an
error message, and unless the -Z option was used, it will not generate an
object file. This can be used to signal an error in conditionally compiled code.