Re: "A diagram of C23 basic types"

On 08/04/2025 15:57, David Brown wrote:

On 08/04/2025 15:32, bart wrote:

On 05/04/2025 18:56, Philipp Klaus Krause wrote:

Am 02.04.25 um 11:57 schrieb bart:

* Where are the fixed-width types from stdint.h?

>
Same as for size_t, etc: They don't exist. Those are not separate types, just typedefs to some other types. E.g. uint16_t could be typedef'ed to unsigned int.
>

>
This is the point I made a few weeks back, but others insisted they were part of C:
>
>
Me:
 >> stdint.h et al are just ungainly bolt-ons, not fully supported by the
 >> language.
>
Keith Thompson:
>
 > No, they're fully supported by the language.  They've been in the ISO
 > standard since 1999.
 >
>
This is an exchange posted on 20-Mar-2025 at 19:10 GMT (header shows 'Thu, 20 Mar 2025 12:10:22 -0700')
>
Clearly, they're not quite as fully supported as short, int etc; they are usually just aliases. But that needn't stop them being shown on such a chart.

 Standard aliases are part of the language standard, and therefore standard and fully supported parts of the language.
 

So, should they have been on that chart?
 > and fully supported parts of the language.
Differences between 'unsigned long long int' and 'uint64_t' up to C23:
                          uint64_t   unsigned long long int
Works without header     No         Yes
Literal suffix           No         Yes (ULL etc)
Dedicated printf format  No         Yes (%llu)
Dedicated scanf format   No         Yes (whatever that might be)
sizeof() might not be 8  No         Maybe
Reserved word[1]         No         Yes
Outside lexical scope[2] No         Yes
Incompatible with
  unsigned long int       No         Yes
[1] Maybe _t names are reserved, but this:
   typedef struct {int x,y;} uint64_t;
compiles cleanly with:
   gcc -std=c23 -Wall -Wextra -pedantic
This means that they could legally be used for any user-defined types.
[2] This is possible with uint64_t:
   #include <stdint.h>
   int main() {
       typedef struct {int x,y;} uint64_t;
   }
You can shadow the names from stdint.h.
So I'd dispute they are as fully supported and 'special' as built-in types.