antlr4 - Why is this left-recursive and how do I fix it? -

i'm learning antlr4 , i'm confused @ 1 point. java-like language, i'm trying add rules constructs member chaining, that:

expr1.methodcall(expr2).methodcall(expr3); 

i'm getting error, saying 2 of rules mutually left-recursive:

expression     : literal     | variablereference     | lparen expression rparen     | statementexpression     | memberaccess     ;  memberaccess: expression dot (methodcall | fieldreference); 

i thought understood why above rule combination considered left-recursive: because memberaccess candidate of expression , memberaccess starts expression.

however, understanding broke down when saw (by looking @ the java example) if move contents of memberaccess expression, got no errors antlr4 (even though still doesn't parse want, seems fall loop):

expression     : literal     | variablereference     | lparen expression rparen     | statementexpression     | expression dot (methodcall | fieldreference)     ; 

1. why first example left-recursive second isn't?
2. and have parse initial line?

the second left-recursive not mutually left recursive. antlr4 can eliminate left-recursive rules inbuilt algorithm. cannot eliminate mutually left recursive rules. there exists algorithm, hardly preserve actions , semantic predicates.