• ParticlePeter (9/9) Aug 25 2020 void main() {
• Mathias LANG (4/13) Aug 25 2020 Yes. You should use `llu`.
• ParticlePeter (6/21) Aug 25 2020 What makes you think I am learning (printf), and what do you mean
• Walter Bright (5/7) Aug 26 2020 That's because printf format checking is a new feature. Your code was ac...
• Jonathan M Davis (6/14) Aug 31 2020 It's the kind of breaking change that's actually nice, since it's findin...

ParticlePeter <ParticlePeter gmx.de> writes:

void main()  {
     import core.stdc.stdio : printf;
     ulong ul = 0;
     printf( "%lu\n", ul );
}

Tested on dmd 2.093 and 2.093.1 (noticed on later first time), 
with flag -m64.
Same message when format specifier is %u.

Is this intended behavior?

Mathias LANG <geod24 gmail.com> writes:

On Tuesday, 25 August 2020 at 08:14:23 UTC, ParticlePeter wrote:
 void main()  {
     import core.stdc.stdio : printf;
     ulong ul = 0;
     printf( "%lu\n", ul );
 }

 Tested on dmd 2.093 and 2.093.1 (noticed on later first time), 
 with flag -m64.
 Same message when format specifier is %u.

 Is this intended behavior?

Yes. You should use `llu`. 
https://en.wikipedia.org/wiki/C_data_types
Also those questions are better suited for the `D.learn` forum.

ParticlePeter <ParticlePeter gmx.de> writes:

On Tuesday, 25 August 2020 at 09:06:27 UTC, Mathias LANG wrote:
 On Tuesday, 25 August 2020 at 08:14:23 UTC, ParticlePeter wrote:
 void main()  {
     import core.stdc.stdio : printf;
     ulong ul = 0;
     printf( "%lu\n", ul );
 }

 Tested on dmd 2.093 and 2.093.1 (noticed on later first time), 
 with flag -m64.
 Same message when format specifier is %u.

 Is this intended behavior?

 Yes. You should use `llu`. 
 https://en.wikipedia.org/wiki/C_data_types

Thanks, I oversaw that a ulong means unsigned long long.

 Also those questions are better suited for the `D.learn` forum.

What makes you think I am learning (printf), and what do you mean 
by 'those questions' ? The code I am talking about is unchanged 
since at least, dmd 2.086, now I am getting the Deprecation 
message.

Walter Bright <newshound2 digitalmars.com> writes:

On 8/25/2020 2:28 AM, ParticlePeter wrote:
 The code I am talking about is unchanged since at least, dmd 2.086, 
 now I am getting the Deprecation message.

That's because printf format checking is a new feature. Your code was actually 
broken before, although it appeared to work. It would likely have failed more 
obviously if there were more argments after ul, or if your machine was
bigendian.

This change uncovered a lot of similar latent bugs in programs.

Jonathan M Davis <newsgroup.d jmdavisprog.com> writes:

On Wednesday, August 26, 2020 10:28:13 PM MDT Walter Bright via Digitalmars-d 
wrote:
 On 8/25/2020 2:28 AM, ParticlePeter wrote:
 The code I am talking about is unchanged since at least, dmd 2.086,
 now I am getting the Deprecation message.

 That's because printf format checking is a new feature. Your code was
 actually broken before, although it appeared to work. It would likely have
 failed more obviously if there were more argments after ul, or if your
 machine was bigendian.

 This change uncovered a lot of similar latent bugs in programs.

It's the kind of breaking change that's actually nice, since it's finding
bugs for you (like when fallthrough on switch statements was banned outside
of empty case statements).

- Jonathan M Davis