Re: [PATCH 08/12] mingw: rely on MSYS2's metadata instead of hard-coding it
- From
Johannes Schindelin <johannes.schindelin@gmx.de>
- Date
- Aug 6, 2026, 12:50 UTC
- Message-ID
- <9f905100-003b-8ef2-3e2e-2f9ed57dda1b@gmx.de>
- In-Reply-To
- <xmqq7bm4qxv6.fsf@gitster.g>
Hi Junio,
On Wed, 5 Aug 2026, Junio C Hamano wrote:
Show 60 quoted lines
> "Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com>
> writes:
> [...]
> > diff --git a/meson.build b/meson.build
> > index 7073d5844d..6ddc461873 100644
> > --- a/meson.build
> > +++ b/meson.build
> > @@ -1318,7 +1318,6 @@ elif host_machine.system() == 'windows'
> >
> > libgit_c_args += [
> > '-DDETECT_MSYS_TTY',
> > - '-DENSURE_MSYSTEM_IS_SET',
> > '-DNATIVE_CRLF',
> > '-DNOGDI',
> > '-DNO_POSIX_GOODIES',
> > @@ -1328,6 +1327,18 @@ elif host_machine.system() == 'windows'
> > '-D__USE_MINGW_ANSI_STDIO=0',
> > ]
> >
> > + msystem = get_option('msystem')
> > + if msystem != ''
> > + mingw_prefix = get_option('mingw_prefix')
> > + if mingw_prefix == ''
> > + mingw_prefix = '/' + msystem.to_lower()
> > + endif
> > + libgit_c_args += [
> > + '-DENSURE_MSYSTEM_IS_SET="' + msystem + '"',
> > + '-DMINGW_PREFIX="' + mingw_prefix + '"'
> > + ]
> > + endif
>
> Lowercase mingw_prefix in Meson world corresponds to MINGW_PREFIX in
> Make world, I guess. -DMINGW_PRFIX gets mingw_prefix which begins
> with a slash.
>
> I do not do Windows or Meson, but doesn't this contradict with what
> we have in [12/12], part of which says:
>
> diff --git a/config.mak.uname b/config.mak.uname
> index 2f7d445eb3..0b63be10b7 100644
> --- a/config.mak.uname
> +++ b/config.mak.uname
> @@ -535,7 +535,9 @@ endif
> compat/win32/pthread.o compat/win32/syslog.o \
> compat/win32/trace2_win32_process_info.o \
> compat/win32/dirent.o
> - COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
> + COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY \
> + -DENSURE_MSYSTEM_IS_SET="\"$(MSYSTEM)\"" -DMINGW_PREFIX="\"$(patsubst /%,%,$(MINGW_PREFIX))\"" \
> + -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
> BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO -ENTRY:wmainCRTStartup -SUBSYSTEM:CONSOLE
> # invalidcontinue.obj allows Git's source code to close the same file
> # handle twice, or to access the osfhandle of an already-closed stdout
>
>
> IOW, -DMINGW_PREFIX passed to the compiler strips leading slash from
> $(MINGW_PREFIX).
>
> Isn't it necessary to strip the leading slash from ming_prefix also
> on the Meson side?Correct. Since Git for Windows does not use Meson to build the project, and since the Visual C-based builds (including CI's `windows-meson-build`) do not use `MSYSTEM`, this was not caught earlier. The next iteration will have the fix.
Ciao, Johannes