ZDoom parser crash

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctype.h>

struct FParseSymbol
{
    int Value;
    char Sym[80];
};

union FParseToken
{
    int val;
    double fval;
    char sym[80];
    char string[80];
    FParseSymbol *symval;
};

static FParseSymbol symbols[10];
bool FindSym (char *sym, FParseSymbol **val)
{
    // Remove loop or if here to fix
    for(unsigned i=0;i<10; i++)
    {
        if (strcmp (symbols[i].Sym, sym) == 0)
        {
            *val = &symbols[i];
            return true;
        }
    }
    return false;
}

int GetToken (char *&sourcep, FParseToken *yylval)
{
    char token[80];
    int toksize;
    int c;

loop:
    while (isspace (c = *sourcep++) && c != 0)
    {
    }

    if (isalpha (c))
    {
        token[0] = c;
        token[1] = c;
        token[2] = c;
        token[3] = c;
        token[4] = c;
        token[5] = c;
        token[6] = c;
        token[7] = c;
        token[8] = c;
        token[9] = c;
        token[10] = c;
        toksize = 10;
        token[toksize] = 0;

        // Remove this if line to fix
        if (FindSym (token, &yylval->symval)) return 0;
        strcpy (yylval->sym, token);

        // Replacing above strcpy with this works
        //memcpy(yylval->sym, token, 80);
        return 0;
    }
    return 0;
}

int main()
{
    char* test = new char[4096];
    strcpy(test, "asdfg asdfgsdfg s dfgsfg");

    FParseToken sym;
    GetToken(test, &sym);
    return 0;
}