diff --git a/tool/src/org/antlr/v4/parse/ANTLRLexer.g b/tool/src/org/antlr/v4/parse/ANTLRLexer.g
index 72f579c86..ab4977cb5 100644
--- a/tool/src/org/antlr/v4/parse/ANTLRLexer.g
+++ b/tool/src/org/antlr/v4/parse/ANTLRLexer.g
@@ -621,7 +621,7 @@ STRING_LITERAL
 @init {
    int len = 0;
 }
-    :  '\'' ( ( ESC_SEQ | ~('\\'|'\'') ) {len++;} )* '\''
+    :  '\'' ( ( ESC_SEQ | ~('\\'|'\''|'\r'|'\n') ) {len++;} )* '\''
     ;
 
 // A valid hex digit specification
diff --git a/tool/test/org/antlr/v4/test/BaseTest.java b/tool/test/org/antlr/v4/test/BaseTest.java
index 9f78a32c3..f87db29dd 100644
--- a/tool/test/org/antlr/v4/test/BaseTest.java
+++ b/tool/test/org/antlr/v4/test/BaseTest.java
@@ -159,6 +159,7 @@ public abstract class BaseTest {
 	protected ATN createATN(Grammar g, boolean useSerializer) {
 		if ( g.atn==null ) {
 			semanticProcess(g);
+			assertEquals(0, g.tool.getNumErrors());
 
 			ParserATNFactory f;
 			if ( g.isLexer() ) {
@@ -169,6 +170,7 @@ public abstract class BaseTest {
 			}
 
 			g.atn = f.createATN();
+			assertEquals(0, g.tool.getNumErrors());
 		}
 
 		ATN atn = g.atn;
diff --git a/tool/test/org/antlr/v4/test/TestATNDeserialization.java b/tool/test/org/antlr/v4/test/TestATNDeserialization.java
index c76c3a93d..d62b7ec23 100644
--- a/tool/test/org/antlr/v4/test/TestATNDeserialization.java
+++ b/tool/test/org/antlr/v4/test/TestATNDeserialization.java
@@ -125,7 +125,7 @@ public class TestATNDeserialization extends BaseTest {
 	@Test public void testLexerEOFInSet() throws Exception {
 		LexerGrammar lg = new LexerGrammar(
 			"lexer grammar L;\n"+
-			"A : 'a' (EOF|'\n') ;\n");
+			"A : 'a' (EOF|'\\n') ;\n");
 		checkDeserializationIsStable(lg);
 	}
 
diff --git a/tool/test/org/antlr/v4/test/TestATNLexerInterpreter.java b/tool/test/org/antlr/v4/test/TestATNLexerInterpreter.java
index c3037a9ea..a88449c99 100644
--- a/tool/test/org/antlr/v4/test/TestATNLexerInterpreter.java
+++ b/tool/test/org/antlr/v4/test/TestATNLexerInterpreter.java
@@ -143,7 +143,7 @@ public class TestATNLexerInterpreter extends BaseTest {
 			"lexer grammar L;\n"+
 			"KEND : 'end' ;\n" +
 			"ID : 'a'..'z'+ ;\n" +
-			"WS : (' '|'\n')+ ;");
+			"WS : (' '|'\\n')+ ;");
 		String expecting = "ID, EOF";
 		//checkLexerMatches(lg, "e", expecting);
 		expecting = "KEND, EOF";
@@ -159,7 +159,7 @@ public class TestATNLexerInterpreter extends BaseTest {
 			"lexer grammar L;\n"+
 			"INT : DIGIT+ ;\n" +
 			"fragment DIGIT : '0'..'9' ;\n" +
-			"WS : (' '|'\n')+ ;");
+			"WS : (' '|'\\n')+ ;");
 		String expecting = "INT, WS, INT, EOF";
 		checkLexerMatches(lg, "32 99", expecting);
 	}
@@ -168,7 +168,7 @@ public class TestATNLexerInterpreter extends BaseTest {
 		LexerGrammar lg = new LexerGrammar(
 			"lexer grammar L;\n"+
 			"CMT : '/*' (CMT | ~'*')+ '*/' ;\n" +
-			"WS : (' '|'\n')+ ;");
+			"WS : (' '|'\\n')+ ;");
 		String expecting = "CMT, WS, CMT, EOF";
 		checkLexerMatches(lg, "/* ick */\n/* /*nested*/ */", expecting);
 	}
@@ -177,7 +177,7 @@ public class TestATNLexerInterpreter extends BaseTest {
 		LexerGrammar lg = new LexerGrammar(
 			"lexer grammar L;\n"+
 			"CMT : '/*' (CMT | .)*? '*/' ;\n" +
-			"WS : (' '|'\n')+ ;");
+			"WS : (' '|'\\n')+ ;");
 
 		String expecting = "CMT, WS, CMT, WS, EOF";
 		checkLexerMatches(lg,
@@ -257,7 +257,7 @@ public class TestATNLexerInterpreter extends BaseTest {
 	@Test public void testEOFAtEndOfLineComment() throws Exception {
 		LexerGrammar lg = new LexerGrammar(
 			"lexer grammar L;\n"+
-			"CMT : '//' ~('\n')* ;\n");
+			"CMT : '//' ~('\\n')* ;\n");
 		String expecting = "CMT, EOF";
 		checkLexerMatches(lg, "//x", expecting);
 	}
@@ -265,7 +265,7 @@ public class TestATNLexerInterpreter extends BaseTest {
 	@Test public void testEOFAtEndOfLineComment2() throws Exception {
 		LexerGrammar lg = new LexerGrammar(
 			"lexer grammar L;\n"+
-			"CMT : '//' ~('\n'|'\r')* ;\n");
+			"CMT : '//' ~('\\n'|'\\r')* ;\n");
 		String expecting = "CMT, EOF";
 		checkLexerMatches(lg, "//x", expecting);
 	}
@@ -276,7 +276,7 @@ public class TestATNLexerInterpreter extends BaseTest {
 	@Test public void testEOFInSetAtEndOfLineComment() throws Exception {
 		LexerGrammar lg = new LexerGrammar(
 			"lexer grammar L;\n"+
-			"CMT : '//' .* (EOF|'\n') ;\n");
+			"CMT : '//' .* (EOF|'\\n') ;\n");
 		String expecting = "CMT, EOF";
 		checkLexerMatches(lg, "//", expecting);
 	}
diff --git a/tool/test/org/antlr/v4/test/TestATNSerialization.java b/tool/test/org/antlr/v4/test/TestATNSerialization.java
index c6f2da748..2ed3a1f92 100644
--- a/tool/test/org/antlr/v4/test/TestATNSerialization.java
+++ b/tool/test/org/antlr/v4/test/TestATNSerialization.java
@@ -358,7 +358,7 @@ public class TestATNSerialization extends BaseTest {
 	@Test public void testLexerEOFInSet() throws Exception {
 		LexerGrammar lg = new LexerGrammar(
 			"lexer grammar L;\n"+
-			"INT : 'a' (EOF|'\n') ;\n");
+			"INT : 'a' (EOF|'\\n') ;\n");
 		String expecting =
 			"max type 1\n" +
 				"0:TOKEN_START -1\n" +
diff --git a/tool/test/org/antlr/v4/test/TestLexerExec.java b/tool/test/org/antlr/v4/test/TestLexerExec.java
index c920192b9..60360c26e 100644
--- a/tool/test/org/antlr/v4/test/TestLexerExec.java
+++ b/tool/test/org/antlr/v4/test/TestLexerExec.java
@@ -202,7 +202,7 @@ public class TestLexerExec extends BaseTest {
 		String grammar =
 			"lexer grammar L;\n"+
 			"CMT : '/*' (CMT | .)*? '*/' ;\n" +
-			"WS : (' '|'\n')+ ;\n"
+			"WS : (' '|'\\n')+ ;\n"
 			/*+ "ANY : .;"*/;
 
 		String expecting =
@@ -240,7 +240,7 @@ public class TestLexerExec extends BaseTest {
 		String grammar =
 			"lexer grammar L;\n"+
 			"CMT : '/*' (CMT | .)+? '*/' ;\n" +
-			"WS : (' '|'\n')+ ;\n"
+			"WS : (' '|'\\n')+ ;\n"
 			/*+ "ANY : .;"*/;
 
 		String expecting =
@@ -382,7 +382,7 @@ public class TestLexerExec extends BaseTest {
 		String grammar =
 			"lexer grammar L;\n" +
 			"STRING_START : '\"' {pushMode(STRING_MODE); more();} ;\n" +
-			"WS : (' '|'\n') {skip();} ;\n"+
+			"WS : (' '|'\\n') {skip();} ;\n"+
 			"mode STRING_MODE;\n"+
 			"STRING : '\"' {popMode();} ;\n"+
 			"ANY : . {more();} ;\n";
@@ -398,7 +398,7 @@ public class TestLexerExec extends BaseTest {
 		String grammar =
 			"lexer grammar L;\n" +
 			"STRING_START : '\"' -> pushMode(STRING_MODE), more ;\n" +
-			"WS : (' '|'\n') -> skip ;\n"+
+			"WS : (' '|'\\n') -> skip ;\n"+
 			"mode STRING_MODE;\n"+
 			"STRING : '\"' -> popMode ;\n"+  // token type 2
 			"ANY : . -> more ;\n";
@@ -414,7 +414,7 @@ public class TestLexerExec extends BaseTest {
 		String grammar =
 			"lexer grammar L;\n" +
 			"STRING_START : '\"' -> mode(STRING_MODE), more ;\n" +
-			"WS : (' '|'\n') -> skip ;\n"+
+			"WS : (' '|'\\n') -> skip ;\n"+
 			"mode STRING_MODE;\n"+
 			"STRING : '\"' -> mode(DEFAULT_MODE) ;\n"+ // ttype 2 since '"' ambiguity
 			"ANY : . -> more ;\n";
@@ -431,7 +431,7 @@ public class TestLexerExec extends BaseTest {
 			"lexer grammar L;\n"+
 			"KEND : 'end' ;\n" + // has priority
 			"ID : 'a'..'z'+ ;\n" +
-			"WS : (' '|'\n')+ ;";
+			"WS : (' '|'\\n')+ ;";
 		String found = execLexer("L.g4", grammar, "L", "end eend ending a");
 		String expecting =
 			"[@0,0:2='end',<1>,1:0]\n" +
@@ -454,7 +454,7 @@ public class TestLexerExec extends BaseTest {
 			"DOT : '.' ;\n" +
 			"ID : 'a'..'z'+ ;\n" +
 			"fragment HexDigit : ('0'..'9'|'a'..'f'|'A'..'F') ;\n" +
-			"WS : (' '|'\n')+ ;";
+			"WS : (' '|'\\n')+ ;";
 		String found = execLexer("L.g4", grammar, "L", "x 0 1 a.b a.l");
 		String expecting =
 			"[@0,0:0='x',<5>,1:0]\n" +