Micro Parser Combinators (mpc) runs in endless loop - c++

Question

I am writing a compiler in C++ (using Visual Studio) for a small scripting language and I use this C parsing library.
So, I followed instructions from the documentation and I ended up on this peace of code:
int main()
{
mpc_parser_t* Int = mpc_new("int");
mpc_parser_t* Char = mpc_new("char");
mpc_parser_t* String = mpc_new("string");
mpc_parser_t* Id = mpc_new("id");
mpc_parser_t* Type = mpc_new("type");
mpc_parser_t* Formal = mpc_new("formal");
mpc_parser_t* Header = mpc_new("header");
mpc_parser_t* FuncDecl = mpc_new("funcdecl");
mpc_parser_t* VarDef = mpc_new("vardef");
mpc_parser_t* Expr = mpc_new("expr");
mpc_parser_t* Call = mpc_new("call");
mpc_parser_t* Atom = mpc_new("atom");
mpc_parser_t* Simple = mpc_new("simple");
mpc_parser_t* SimpleList = mpc_new("simplelist");
mpc_parser_t* Stmt = mpc_new("stmt");
mpc_parser_t* FuncDef = mpc_new("funcdef");
mpc_parser_t* Program = mpc_new("program");
/* Define them with the following Language */
mpca_lang(MPCA_LANG_DEFAULT,
" \
int : /-?[0-9]+/ ; \
char : /'[a-zA-Z0-9!##$%^&*()\\_+-,.\\/<>?;'|\"`~]'/ ; \
string : /\"(\\\\.|[^\"])*\"/ ; \
id : /[a-zA-Z][a-zA-Z0-9_-]*/ ; \
type : \"int\" | \"bool\" | \"char\" | <type> '[' ']' | \"list\" '[' <type> ']' ; \
formal : (\"ref\")? <type> <id> (',' <id>)* ; \
header : <type>? <id> '(' (<formal> (';' <formal>)*)? ')' ; \
funcdecl : \"decl\" <header> ; \
vardef : <type> <id> (',' <id>)* ; \
expr : <atom> | <int> | <char> | '(' <expr> ')' \
| ('+' | '-') <expr> | <expr> ('+' | '-' | '*' | '/' | \"mod\") <expr> \
| <expr> ('=' | \"<>\" | '<' | '>' | \"<=\" | \">=\") <expr> \
| \"true\" | \"false\" | \"not\" <expr> | <expr> (\"and\" | \"or\") <expr> \
| \"new\" <type> '[' <expr> ']' | \"nil\" | \"nil?\" '(' <expr> ')' \
| <expr> '#' <expr> | \"head\" '(' <expr> ')' | \"tail\" '(' <expr> ')' ; \
call : <id> '(' (<expr> (',' <expr>)*)? ')' ; \
atom : <id> | <string> | <atom> '[' <expr> ']' | <call> ; \
simple : \"skip\" | <atom> \":=\" <expr> | <call> ; \
simplelist : <simple> (',' <simple>)* ; \
stmt : <simple> | \"exit\" | \"return\" <expr> \
| \"if\" <expr> ':' <stmt>+ (\"elif\" <expr> ':' <stmt>+)* \
(\"else\" ':' <stmt>+)? \"end\" \
| \"for\" <simplelist> ';' <expr> ';' <simplelist> ':' <stmt>+ \"end\" ; \
funcdef : \"def\" <header> ':' (<funcdef> | <funcdecl> | <vardef>)* <stmt>+ \"end\" ; \
program : /^/ <funcdef> /$/ ; \
",
Int, Char, String, Id, Type, Formal, Header, FuncDecl, VarDef, Expr,
Call, Atom, Simple, SimpleList, Stmt, FuncDef, Program);
mpc_result_t r;
char* input = "def hey () : return 1 end";
if(mpc_parse("input", input, Program, &r))
{
mpc_ast_print((mpc_ast_t*)r.output);
mpc_ast_delete((mpc_ast_t*)r.output);
}
else
{
mpc_err_print(r.error);
mpc_err_delete(r.error);
}
PAUSE("Press any key to continue . . .");
/* Undefine and Delete our Parsers */
mpc_cleanup(17, Int, Char, String, Id, Type, Formal, Header, FuncDecl, VarDef, Expr,
Call, Atom, Simple, SimpleList, Stmt, FuncDef, Program);
return 0;
}
The problem is that I run into an huge loop in mpc_parse. That loop never actually reaches the end. After some time I get this exception:
Unhandled exception at 0x00CBBC9C in TonyCC.exe: 0xC0000005: Access violation reading location 0x0000000C.
I don't know why. I suspect there is something wrong with my grammar but I cannot figure out what.
If someone has used this library before, do you have any idea what the problem might be?
Note: I know it is difficult to read the grammar from C code so here is an image of the grammar: