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Re: Two C code questions

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On 2017-03-14, MehdiAmini <atorrses@gmail.com> wrote:
> // Clang version 3.8.0
>
> // Question 1:
> #include <stdio.h>
> #include <stdlib.h>
> #include <inttypes.h>
>
> void my_alloc( void *, size_t );
>
> int main(void)
> {
>      unsigned *u_ptr = NULL;
>      //unsigned *u_ptr; // Why using this instead of above line causes 
> core dump?
>
>      my_alloc(u_ptr,sizeof(*u_ptr));
>
>      free(u_ptr);
>      return EXIT_SUCCESS;
> }
>
> void my_alloc( void *v_ptr, size_t size )
> {
>      v_ptr = malloc(size);
>      if( v_ptr == NULL )
>      {
>          fprintf(stderr,"Memory allocation failed.\n");
>          exit(EXIT_FAILURE);
>      }
>
>      return ;
> }
>
> // Question 2:
> #include <stdio.h>
> #include <stdlib.h>
> #include <inttypes.h>
>
> #define N 6
> //static const long N = 6; // Why using this instead of above line 
> causes error?
>
> int main(void)
> {
>      uint64_t ui[N] = {0};
>
>      return EXIT_SUCCESS;
> }

Both questions are answered in the C language FAQ

  http://c-faq.com

look for questions 4.8 and 8.11 .

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Two C code questions MehdiAmini <atorrses@gmail.com> - 2017-03-14 07:15 +0330
  Re: Two C code questions Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-03-13 22:13 -0600
  Re: Two C code questions Ian Collins <ian-news@hotmail.com> - 2017-03-14 17:16 +1300
  Re: Two C code questions Ike Naar <ike@iceland.freeshell.org> - 2017-03-14 07:20 +0000
    Re: Two C code questions MehdiAmini <atorrses@gmail.com> - 2017-03-14 12:01 +0330
      Re: Two C code questions Ike Naar <ike@iceland.freeshell.org> - 2017-03-14 19:23 +0000
        Re: Two C code questions Keith Thompson <kst-u@mib.org> - 2017-03-14 12:40 -0700
  Re: Two C code questions scott@slp53.sl.home (Scott Lurndal) - 2017-03-14 12:44 +0000
  Re: Two C code questions Keith Thompson <kst-u@mib.org> - 2017-03-14 08:53 -0700
    Re: Two C code questions MehdiAmini <atorrses@gmail.com> - 2017-03-15 14:05 +0330
  Re: Two C code questions John Bode <jfbode1029@gmail.com> - 2017-03-14 10:38 -0700
    Re: Two C code questions Keith Thompson <kst-u@mib.org> - 2017-03-14 11:49 -0700
      Re: Two C code questions John Bode <jfbode1029@gmail.com> - 2017-03-14 14:14 -0700

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