Thread: pointer and struct

Originally Posted by misplaced

lol........i love it...forget the inline keyword.....just go ahead and put your functions inline

>TRY koo= (struct p *) malloc(sizeof(p));
Lose the cast, it only serves to hide more subtle errors. And it should be:

Code:

koo = malloc ( sizeof ( struct p ) );

Because p is not a typedef'd struct, you must have the struct keyword unless compiling as C++ by accident. Though the OP had the right of it with this:

Code:

koo = malloc ( sizeof *koo );

Originally Posted by Prelude

Code:

 koo = malloc ( sizeof *koo );

Are you sure about this? GCC gives me a warning about this, even without any -W* parameters used.

Code:

 typedef struct {
   int a;
 } TTest;
 
 int main() {
   TTest *ptTest;
   ptTest= malloc(sizeof(TTest));
 
   ptTest->a= 1;
   return ptTest->a;
 }

Code:

 nyda, nyda/ $ LC_ALL="C" gcc test.c -o test
 test.c: In function `main':
 test.c:7: warning: assignment makes pointer from integer without a cast

> test.c:7: warning: assignment makes pointer from integer without a cast
Which is precisely the reason for removing the cast in the first place.
The correct fix is to include stdlib.h to make the message go away.
The incorrect fix is to cast it to make the message go away.

Further, if you get messages which complain about void* conversions when using malloc, it means you're compiling your C code with a C++ compiler. The fix in this case is to either use a C compiler, or continue with C++ and replace the malloc call with a 'new' call (and replace free() with delete)

Originally Posted by Salem

> test.c:7: warning: assignment makes pointer from integer without a cast
Which is precisely the reason for removing the cast in the first place.
The correct fix is to include stdlib.h to make the message go away.
The incorrect fix is to cast it to make the message go away.

Thanks Salem. I was already wondering why it was saying "integer without a cast". So I just forgot to include the malloc definition .