Re: bison and malloc

[s88]

On 10/11/06, Tim Van Holder <address@hidden> wrote:
> s88 wrote:
> > Hi all:
> >   I'm confused with the bison and malloc right now...
> > I'm using the Bison 2.0 on Ubuntu(Linux) 6.06, and everytime when I use
> > the malloc(actually is strdup) in the production rules. It will cause an
> > unpredictable
> > segmentation fault. The stack size on my system is set unlimited.
> > Every time after using the dynamic allocate memory, I'll free the memory
> by
> > myself.
> >
> > What cause this fault, and how to fix it?
> >
> > Any idea?
> >
> > Thankx!!!!!
> > Dave.
>
> The most likely cause would be that you're free()ing twice.
> But without a little bit of code to illustrate what you're doing, it's
> very hard to diagnose a crash bug.
well..thank U all first!!
Let me show my code here...
I want to parse the sequence such likes X1,X2,{Y1,X4,Z5}
BTW, I'm using the GTK library to malloc and free, but I'm sure the question
is not on the GTK.


arguements : arguement{
       $$ = $1;
}| arguements ',' arguement{
       GList *_l = g_list_concat($1,$3);
       $$ = _l;
};


arguement:'{' arguements '}' {
       $$ = $2;
}|'[' arguements ']' {
       $$ = $2;
}|UID{
       $$ = create_arglist($1);
}|ID{
       $$ = create_arglist($1);
}|INTEGER{
}|EUINT64VAL{
};

#include <gtk/gtk.h>
GList* create_arglist(const gchar* str){
       GList* _list = NULL;
       gchar* _str  = g_strdup(str);
       _list = g_list_append(_list,_str);
       return _list;
}

void arglist_free(GList* list){
       GList *_cur = list;
       GList *_next;
       while(_cur !=NULL){
               _next = _cur->next;
               g_free(_cur->data);
               _cur = _next;
       }
       g_list_free(list);

Dave.
--
System  on Chip Design  Lab.
Dept. of Computer Science and Information Engineering,
National Chung Cheng University
E-mail : address@hidden