nqasm: Improve parsing at end of file

Bison's implicit $accept rule ends with the END token.  The fact that input
could also end with END (via the line non-terminal) resulted in a shift
reduce conflict.

We resolve the conflict by modifying the lexer so that if it encounters end
of file partway through a line, it produces a final EOL token before EOF.

1 files changed, 4 insertions, 1 deletions

diff --git a/lexer.l b/lexer.l
index 9a34d66..6b6b121 100644
--- a/lexer.l
+++ b/lexer.l
@@ -55,7 +55,10 @@ EOI        [ \t\n#]
 <inst>nop/{EOI}          { BEGIN(args);    return T_NOP;    }
 
 {SP}*{COMMENT}?\n        { BEGIN(INITIAL); return T_EOL;    }
-{SP}*{COMMENT}           { BEGIN(INITIAL); return T_SPACE;  }
+{SP}*{COMMENT}           { BEGIN(INITIAL); return T_EOL;    }
 {SP}+                    {                 return T_SPACE;  }
 
+<INITIAL><<EOF>>         {                 return 0;        }
+<<EOF>>                  { BEGIN(INITIAL); return T_EOL;    }
+
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