bug#42822: Build of master db3a7df fails with MINGW64 console of MSYS2

bug#42822: Build of master db3a7df fails with MINGW64 console of MSYS2

[Yasuhiro KIMURA]

I checked out master db3a7df and built it with MINGW64 console of
MSYS2 on 64bit Windows 10 version 1909. Then I got following error.

----------------------------------------------------------------------
  CC       search.o
  CC       regex-emacs.o
  CC       undo.o
  CC       alloc.o
  CC       pdumper.o
pdumper.c: In function 'dump_read_all':
pdumper.c:5078:60: error: conversion from 'size_t' {aka 'long long unsigned int'} to 'unsigned int' may change value [-Werror=conversion]
 5078 |       ssize_t chunk = read (fd, (char *) buf + bytes_read, chunk_to_read);
      |                                                            ^~~~~~~~~~~~~
cc1.exe: some warnings being treated as errors
make[1]: *** [Makefile:401: pdumper.o] Error 1
make[1]: Leaving directory '/c/Users/yasu/Work/Emacs/master/emacs/src'
make: *** [Makefile:424: src] Error 2
(MINGW64)yasu@rolling[1188]% 
----------------------------------------------------------------------

According to the result of git bisect, following commit is the cause
of the problem.

----------------------------------------------------------------------
commit 9e4e4775364490d31406f247237934dd7f203808 (HEAD)
Author: Paul Eggert <eggert@cs.ucla.edu>
Date:   Tue Aug 11 02:16:54 2020 -0700

    In pdumper, simplify INT_MAX computation

    * src/pdumper.c (dump_read_all): Avoid unnecessary cast.
    Also, round down to page size, as sysdep.c does.
    Also, don t assume INT_MAX <= UINT_MAX (!).
----------------------------------------------------------------------

If I go back to master db3a7df and revert this commit, then build
completes successfully.

---
Yasuhiro KIMURA

bug#42822: Build of master db3a7df fails with MINGW64 console of MSYS2

[Eli Zaretskii]

> Date: Wed, 12 Aug 2020 08:27:41 +0900 (JST)
> From: Yasuhiro KIMURA <yasu@utahime.org>
> 
> I checked out master db3a7df and built it with MINGW64 console of
> MSYS2 on 64bit Windows 10 version 1909. Then I got following error.
> 
> ----------------------------------------------------------------------
>   CC       search.o
>   CC       regex-emacs.o
>   CC       undo.o
>   CC       alloc.o
>   CC       pdumper.o
> pdumper.c: In function 'dump_read_all':
> pdumper.c:5078:60: error: conversion from 'size_t' {aka 'long long unsigned int'} to 'unsigned int' may change value [-Werror=conversion]
>  5078 |       ssize_t chunk = read (fd, (char *) buf + bytes_read, chunk_to_read);
>       |                                                            ^~~~~~~~~~~~~
> cc1.exe: some warnings being treated as errors
> make[1]: *** [Makefile:401: pdumper.o] Error 1
> make[1]: Leaving directory '/c/Users/yasu/Work/Emacs/master/emacs/src'
> make: *** [Makefile:424: src] Error 2
> (MINGW64)yasu@rolling[1188]% 

Please try again, this should be fixed now.

bug#42822: Build of master db3a7df fails with MINGW64 console of MSYS2

[Yasuhiro KIMURA]

From: Eli Zaretskii <eliz@gnu.org>
Subject: Re: bug#42822: Build of master db3a7df fails with MINGW64 console of MSYS2
Date: Wed, 12 Aug 2020 17:18:33 +0300

> Please try again, this should be fixed now.

I confirmed the preblem is fixed with commit 4491a55a.

bug#42822: Build of master db3a7df fails with MINGW64 console of MSYS2

[Stefan Kangas]

Yasuhiro KIMURA <yasu@utahime.org> writes:

> I confirmed the preblem is fixed with commit 4491a55a.

I'm therefore closing this bug report.