Bison calling yyerror and printing success

Question

For some reason when trying to use bison and test input on it I constantly get both a success and a failure every time no matter what. I am not sure what I am doing wrong. Here is my .y file:

%{
#include <stdio.h>
int yylex(void);
int yyerror(char *);
%}
%token LEFTPAREN RIGHTPAREN ASSIGNMENT SEMICOLON IF THEN ELSE BEGIN END WHILE
%token DO PROGRAM VAR AS INT BOOL WRITEINT READINT NUMBER LITERAL
%token OP2 OP3 OP4 IDENTIFIER
%start program
%%
program : PROGRAM declerations BEGIN statementSequence END
;
declerations : VAR IDENTIFIER AS type SEMICOLON declerations |
;
type : INT | BOOL
;
statementSequence : statement SEMICOLON statementSequence |
;
statement : assignment | ifStatement | whileStatement | writeInt
;
assignment : IDENTIFIER ASSIGNMENT expression | IDENTIFIER ASSIGNMENT READINT
;
ifStatement : IF expression THEN statementSequence elseClause END
;
elseClause : ELSE statementSequence |
;
whileStatement : WHILE expression DO statementSequence END
;
writeInt : WRITEINT expression
;
expression : simpleExpression | simpleExpression OP4 simpleExpression
;
simpleExpression : term OP3 term | term
;
term : factor OP2 factor | factor
;
factor : IDENTIFIER | NUMBER | LITERAL | LEFTPAREN expression RIGHTPAREN
;
%%
int yyerror(char *s) {
  printf("yyerror : %s\n",s);
}
int main(){
  yyparse();
  printf("SUCCESS\n");
  return 0;
}

Answer 1

yyparse() returns 0 if the parse succeeded, 1 if it failed, and 2 if it ran out of memory. But you ignore the return value and always print "Success". So it shouldn't be a surprise that "Success" is printed even if the parse failed. What would stop that from happening?