All diagnostic messages are issued as complete, self-explanatory messages. A typical diagnostic message from the assembler is produced in the form:

filename,linenumber level[tag]: message

where filename is the name of the source file in which the error was encountered; linenumber is the line number at which the assembler detected the error; level is the level of seriousness of the diagnostic; tag is a unique tag that identifies the diagnostic message; message is a self-explanatory message, possibly several lines long.

Diagnostic messages are displayed on the screen, and printed in the optional list file. In the IAR Embedded Workbench IDE, diagnostic messages are displayed in the Build messages window.