[PATCH 0/1] git-compat-util.h: drop the PRIuMAX definition

[PATCH 0/1] git-compat-util.h: drop the PRIuMAX definition

[Hariom Verma via GitGitGadget]

Git's code base already seems to be using PRIdMAX without any such fallback
definition for quite a while (75459410edd (json_writer: new routines to
create JSON data, 2018-07-13), to be precise, and the first Git version to
include that commit was v2.19.0).

Therefore it should be safe to drop the fallback definition for PRIuMAX in
git-compat-util.h.

This addresses https://github.com/gitgitgadget/git/issues/399

Hariom Verma (1):
  git-compat-util.h: drop the `PRIuMAX` definition

 git-compat-util.h | 4 ----
 1 file changed, 4 deletions(-)


base-commit: d9f6f3b6195a0ca35642561e530798ad1469bd41
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-473%2Fharry-hov%2Fpriumax-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-473/harry-hov/priumax-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/473
-- 
gitgitgadget

[PATCH 1/1] git-compat-util.h: drop the `PRIuMAX` definition

[Hariom Verma via GitGitGadget]

From: Hariom Verma <hariom18599@gmail.com>

Git's code base already seems to be using `PRIdMAX` without any such
fallback definition for quite a while (75459410edd (json_writer: new
routines to create JSON data, 2018-07-13), to be precise, and the
first Git version to include that commit was v2.19.0).

Therefore it should be safe to drop the fallback definition for
`PRIuMAX` in `git-compat-util.h`.

This addresses https://github.com/gitgitgadget/git/issues/399

Signed-off-by: Hariom Verma <hariom18599@gmail.com>
---
 git-compat-util.h | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/git-compat-util.h b/git-compat-util.h
index 607dca7534..ba710cfa6c 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -320,10 +320,6 @@ char *gitdirname(char *);
 #define PATH_MAX 4096
 #endif
 
-#ifndef PRIuMAX
-#define PRIuMAX "llu"
-#endif
-
 #ifndef SCNuMAX
 #define SCNuMAX PRIuMAX
 #endif
-- 
gitgitgadget

Re: [PATCH 1/1] git-compat-util.h: drop the `PRIuMAX` definition

[Jeff King]

On Sun, Nov 24, 2019 at 01:09:23PM +0000, Hariom Verma via GitGitGadget wrote:

> From: Hariom Verma <hariom18599@gmail.com>
> 
> Git's code base already seems to be using `PRIdMAX` without any such
> fallback definition for quite a while (75459410edd (json_writer: new
> routines to create JSON data, 2018-07-13), to be precise, and the
> first Git version to include that commit was v2.19.0).
> 
> Therefore it should be safe to drop the fallback definition for
> `PRIuMAX` in `git-compat-util.h`.

I noticed this recently, too, and wondered if it was time for a cleanup.

We do sometimes get portability reports more than a year after the
problem was introduced. But I think this one is pretty safe. PRIuMAX is
in C99, and we've been picking up other C99-isms without complaint.

I was curious what system originally spurred this. The PRIuMAX
definition was originally added in 3efb1f343a (Check for PRIuMAX rather
than NO_C99_FORMAT in fast-import.c., 2007-02-20). But it was replacing
a construct that was introduced in 579d1fbfaf (Add NO_C99_FORMAT to
support older compilers., 2006-07-30), which talks about gcc 2.95.
That's pretty ancient at this point.

> diff --git a/git-compat-util.h b/git-compat-util.h
> index 607dca7534..ba710cfa6c 100644
> --- a/git-compat-util.h
> +++ b/git-compat-util.h
> @@ -320,10 +320,6 @@ char *gitdirname(char *);
>  #define PATH_MAX 4096
>  #endif
>  
> -#ifndef PRIuMAX
> -#define PRIuMAX "llu"
> -#endif
> -

This part of the patch looks obviously correct. :) But...

>  #ifndef SCNuMAX
>  #define SCNuMAX PRIuMAX
>  #endif

Can we likewise ditch the fallback definition for SCNuMAX? And PRIu32,
etc? It seems likely any platform would either have all of them or none.

-Peff

Re: [PATCH 1/1] git-compat-util.h: drop the `PRIuMAX` definition

[Carlo Arenas]

On Sun, Nov 24, 2019 at 9:11 AM Jeff King <peff@peff.net> wrote:
>
> We do sometimes get portability reports more than a year after the
> problem was introduced. But I think this one is pretty safe. PRIuMAX is
> in C99, and we've been picking up other C99-isms without complaint.

I think the problem might come from places where the default compiler
is still not C99 by default (ex: old CentOS) and any other places
using gcc < 5 which is less ancient

Carlo

Re: [PATCH 1/1] git-compat-util.h: drop the `PRIuMAX` definition

[Carlo Arenas]

On Sun, Nov 24, 2019 at 9:40 AM Carlo Arenas <carenas@gmail.com> wrote:
>
> I think the problem might come from places where the default compiler
> is still not C99 by default (ex: old CentOS)

CentOS 6.10 (using gcc 4.4.7) compiles this without problems by
default so nothing to worry about, sorry for the red herring

Carlo

PS. non GNU89 (AKA ANSI) mode will obviously break but not ONLY
because of this change

Re: [PATCH 1/1] git-compat-util.h: drop the `PRIuMAX` definition

[Junio C Hamano]

Jeff King <peff@peff.net> writes:

> On Sun, Nov 24, 2019 at 01:09:23PM +0000, Hariom Verma via GitGitGadget wrote:
>
>> From: Hariom Verma <hariom18599@gmail.com>
>> 
>> Git's code base already seems to be using `PRIdMAX` without any such
>> fallback definition for quite a while (75459410edd (json_writer: new
>> routines to create JSON data, 2018-07-13), to be precise, and the
>> first Git version to include that commit was v2.19.0).
>> 
>> Therefore it should be safe to drop the fallback definition for
>> `PRIuMAX` in `git-compat-util.h`.
>
> I noticed this recently, too, and wondered if it was time for a cleanup.

While I agree with the conclusion, I do not think I agree with the
above "Therefore (implying that the lack of need for fallback
PRIdMAX means the same for PRIuMAX) it should be safe" as a good
justification.  That reasoning assumes that the outside world is
much saner than us.  We thought PRIuMAX fallback necessary while a
counterpart for PRIdMAX unneeded---the outside world could have made
a similar mistake and in the opposite way (i.e. only defined PRIdMAX
while leaving PRIuMAX undefined).

But I do agree with the alternative justification in the following
two paragraphs you have given, which are ...

> We do sometimes get portability reports more than a year after the
> problem was introduced. But I think this one is pretty safe. PRIuMAX is
> in C99, and we've been picking up other C99-isms without complaint.
>
> I was curious what system originally spurred this. The PRIuMAX
> definition was originally added in 3efb1f343a (Check for PRIuMAX rather
> than NO_C99_FORMAT in fast-import.c., 2007-02-20). But it was replacing
> a construct that was introduced in 579d1fbfaf (Add NO_C99_FORMAT to
> support older compilers., 2006-07-30), which talks about gcc 2.95.
> That's pretty ancient at this point.

... these.

> This part of the patch looks obviously correct. :) But...
>
>>  #ifndef SCNuMAX
>>  #define SCNuMAX PRIuMAX
>>  #endif
>
> Can we likewise ditch the fallback definition for SCNuMAX? And PRIu32,
> etc? It seems likely any platform would either have all of them or none.

I guess that's also a C99-ism that we can use?

Thanks, both.

Re: [PATCH 1/1] git-compat-util.h: drop the `PRIuMAX` definition

[Junio C Hamano]

Junio C Hamano <gitster@pobox.com> writes:

>> Can we likewise ditch the fallback definition for SCNuMAX? And PRIu32,
>> etc? It seems likely any platform would either have all of them or none.
>
> I guess that's also a C99-ism that we can use?
>
> Thanks, both.

Here is what I have locally for now.

1:  98f866a929 ! 1:  ebc3278665 git-compat-util.h: drop the `PRIuMAX` definition
    @@ Metadata
     Author: Hariom Verma <hariom18599@gmail.com>
     
      ## Commit message ##
    -    git-compat-util.h: drop the `PRIuMAX` definition
    +    git-compat-util.h: drop the `PRIuMAX` and other fallback definitions
     
         Git's code base already seems to be using `PRIdMAX` without any such
         fallback definition for quite a while (75459410edd (json_writer: new
         routines to create JSON data, 2018-07-13), to be precise, and the
    -    first Git version to include that commit was v2.19.0).
    +    first Git version to include that commit was v2.19.0).  Having a
    +    fallback definition only for `PRIuMAX` is a bit inconsistent.
     
    -    Therefore it should be safe to drop the fallback definition for
    -    `PRIuMAX` in `git-compat-util.h`.
    +    We do sometimes get portability reports more than a year after the
    +    problem was introduced.  This one should be fairly safe.  PRIuMAX is
    +    in C99 (for that matter, SCNuMAX, PRIu32 and others also are), and
    +    we've been picking up other C99-isms without complaint.
     
    -    This addresses https://github.com/gitgitgadget/git/issues/399
    +    The PRIuMAX fallback definition was originally added in 3efb1f343a
    +    (Check for PRIuMAX rather than NO_C99_FORMAT in fast-import.c.,
    +    2007-02-20). But it was replacing a construct that was introduced in
    +    an even earlier commit, 579d1fbfaf (Add NO_C99_FORMAT to support
    +    older compilers., 2006-07-30), which talks about gcc 2.95.
    +
    +    That's pretty ancient at this point.
     
         Signed-off-by: Hariom Verma <hariom18599@gmail.com>
    +    Helped-by: Jeff King <peff@peff.net>
    +    [jc: tweaked both message and code, taking what peff wrote]
         Signed-off-by: Junio C Hamano <gitster@pobox.com>
     
      ## git-compat-util.h ##
    @@ git-compat-util.h: char *gitdirname(char *);
     -#define PRIuMAX "llu"
     -#endif
     -
    - #ifndef SCNuMAX
    - #define SCNuMAX PRIuMAX
    - #endif
    +-#ifndef SCNuMAX
    +-#define SCNuMAX PRIuMAX
    +-#endif
    +-
    +-#ifndef PRIu32
    +-#define PRIu32 "u"
    +-#endif
    +-
    +-#ifndef PRIx32
    +-#define PRIx32 "x"
    +-#endif
    +-
    +-#ifndef PRIo32
    +-#define PRIo32 "o"
    +-#endif
    +-
    + typedef uintmax_t timestamp_t;
    + #define PRItime PRIuMAX
    + #define parse_timestamp strtoumax

Re: [PATCH 1/1] git-compat-util.h: drop the `PRIuMAX` definition

[Jeff King]

On Mon, Nov 25, 2019 at 11:45:29AM +0900, Junio C Hamano wrote:

> Junio C Hamano <gitster@pobox.com> writes:
> 
> >> Can we likewise ditch the fallback definition for SCNuMAX? And PRIu32,
> >> etc? It seems likely any platform would either have all of them or none.
> >
> > I guess that's also a C99-ism that we can use?
> >
> > Thanks, both.
> 
> Here is what I have locally for now.

Yes, that looks good to me (and yes, those other format macros are in
C99, too).

-Peff