6.2 Translation

ISO Standard Implementation
“How a diagnostic is identified (3.10, 5.1.1.3).”
By default, when compiling on the command-line the following formats are used. The string (warning) is only displayed for warning messages.

filename:line:column:{error/warning}: message

“Whether each nonempty sequence of white-space characters other than new-line is retained or replaced by one space character in translation phase 3 (5.1.1.2).”
The compiler will replace each leading or interleaved whitespace character sequences with a space. A trailing sequence of whitespace characters is replaced with a new-line.