Thread: error while allocating memory

Hi !

I am getting problem while allocating memory through malloc.Can any body explain me reason

and solution regarding this.

The code is as follow:

Code:

#include<stdlib.h>
#include<stdio.h>
struct NODE
{
    struct NODE* next;
   int data;
};


void insert(struct NODE* p,int value)
{
 if(p==NULL)
{ 
  struct NODE* q=(struct NODE *)malloc(sizeof(struct NODE)); // ERROR 
  p=q;
 q->next=NULL;
}
else
{
 while(p->next!=NULL)
      {
        p=p->next;
     }
 ////code 
 
}
}

void main()
{
  struct NODE* ptr;
 ptr=NULL;

 int choice,i,num;
printf("\n Enter no. of items");
scanf("%d",&choice);
for(i=0;i<choice;i++)
{
  scanf("%d",&num);
   insert(ptr,num);
}
}

The compiler gives following in line above ERROR:

syntax error: missing ' ; ' before 'type'

Can any explain me what is this error and ho to remove it.

thanks

bargi

What is the whole code, #includes and all?

If this is the whole code, you are missing these:

Code:

#include <stdio.h>
#include <stdlib.h>

Visit the FAQ for issues such as void main(), how to read a number from the command line, casting the return value of malloc, and other issues for the newcomer.

Okay, don't edit posts like that -- it makes a thread hard to follow.

Copy and paste the whole thing always -- hopefully we've got the figured out.

Copying and pasting your "whole" code as of the latest edit, the only issue I get is with using void main(), so you are apparently a glutton for punishment.

So... what compiler are you using? And could you copy and paste the actual error message?

Odd... I get this:

Code:

H:\Projects\test.c(34) : error C2143: syntax error : missing ';' before 'type'
H:\Projects\test.c(36) : error C2065: 'choice' : undeclared identifier
H:\Projects\test.c(37) : error C2065: 'i' : undeclared identifier
H:\Projects\test.c(39) : error C2065: 'num' : undeclared identifier

Which tells me that this line is the problem:

Code:

   struct NODE* ptr;
   ptr=NULL;

   int choice,i,num;

Which means that this statement should not precede variable declarations.

Better luck with this?

Code:

   struct NODE* ptr=NULL;

   int choice,i,num;

For C90, you can't have statements after declarations/initializations.

Here you have a declaration, a statement, and more declarations.

Code:

   struct NODE* ptr;
   ptr=NULL;

   int choice,i,num;

Ensuring that only declarations/initializations occur before statements "fixes" it.

Code:

   struct NODE* ptr=NULL;

   int choice,i,num;

The compiler reads it differently (and after a long time, you may too).

Originally Posted by Dave_Sinkula

For C90, you can't have statements after declarations/initializations.

Dave???? Have you gone mad??? I sure hope that one can have statements _AFTER_ declarations. . . it'd be quite odd to have something like:

Code:

for (i = 0; i < z; i++){
    k = i*q+x;
}

int i, z, k, q, x;

That would just be insane. . . and a bit hard to follow. You being a bit lysdexic tonight?

EDIT: BTW, to the OP, Dave actually means that for C90 one cannot have declarations after statements.

Originally Posted by Kennedy

Dave???? Have you gone mad???

That would just be insane. . . and a bit hard to follow. You being a bit lysdexic tonight?

Yes.

[At least no one caught my issue with left/right earlier.]