Updated match names.

src/lex.l

@@ -3,19 +3,19 @@
 #include "y.tab.h"
 %}
 reg     \$[a-zA-Z0-9]+
-word    [a-zA-Z0-9_\.]+
+label   [a-zA-Z0-9_\.]+
 int     [0-9]+
 %%
 
 [\n]                { return NL; }                              /* Newline */
 #.*                 { yylval.sval = yytext; return COMMENT; }   /* Comment */
 \..*                { yylval.sval = yytext; return DIRECTIVE; } /* Assembly directive */
-{word}:             { yylval.sval = yytext; return LABEL; }     /* Label */
+{label}:            { yylval.sval = yytext; return LABEL; }     /* Label */
 {reg}               { yylval.sval = yytext; return REG; }       /* Registry address */
 {int}               { yylval.ival = atoi(yytext); return INT; } /* Integer */
 {int}(\({reg}\))?   { yylval.sval = yytext; return OFFSET; }    /* Registry offset */
-[a-z\.]+            { yylval.sval = yytext; return INSTR; }     /* Instruction */
-{word}              { yylval.sval = yytext; return REF; }       /* Label reference */
+[a-z0-9\.]+         { yylval.sval = yytext; return INSTR; }     /* Instruction */
+{label}             { yylval.sval = yytext; return REF; }       /* Label reference */
 [,]                 { return COMMA; }                           /* Comma */
 
 [ \t]+              ;                                           /* Ignore whitespace */