//line directive does not support source file names containing colons #2543
Description
by jmillikin:
The //line directive used for altering error location strings is not parsed properly by the Go compiler, if the filename it sets contains colons. Given an original file named "support/lang:go.def", which is processed to generate a Go source file, an example // line directive would be: //line support/lang:go.def:1 Which cannot be parsed. Three proposed solutions: 1. Introduce an escape character, such as \, so that colons in the filename may be escaped. 2. Use full string literal syntax for the filename, similar to C's #line directive. This would include escape characters as above. 3. Read the lexbuf until EOF. Split on position of the last colon found. Everything before the last colon is the filename, anything after is the line. #3 seems like the easiest and safest to implement, because the only cases where it changes the behavior are currently invalid anyway.