A grammar containing Unicode code point references for newlines (carriage return and line feed) may produce invalid Java code.

Sample grammar:

grammar Demo;
linebreak: LF
         | CR
         ;
CR : '\u000D';
LF : '\u000A';

Snippet from resulting DemoLexer.java:

	private static final String[] _LITERAL_NAMES = {
		null, "'\u000D'", "'\u000A'"
	};
	private static final String[] _SYMBOLIC_NAMES = {
		null, "CR", "LF"
	};

This will fail to compile. It turns out that since the Java compiler interprets Unicode character escapes before parsing, "\u000D" is equivalent to having a literal carriage return in the middle of a string. Instead of \u000D and \u000A, ANTLR should emit \r and \n.

• I am not submitting a question on how to use ANTLR; instead, go to antlr4-discussion google group or ask at stackoverflow
• I have done a search of the existing issues to make sure I'm not sending in a duplicate