Basil L. Contovounesios wrote:
> >> dist-hook:
> >> echo '$(VERSION)' > $(distdir)/.tarball-version
> >>
> >> whereas the other writes the target directly.
> >
> > Here it does so because the file is inside a temporary directory. If
> > the "make dist" rule fails, the user has to remove the temporary directory
> > entirely anyway, and that will also take care of the empty file.
>
> Does this imply that writing to a temporary file first is never needed
> under distdir?
No. It's never needed under $(distdir) *if* the Makefile rule fails when the
command fails.
> I'm thinking of the examples in (info "(gnulib) gitlog-to-changelog")
> for instance, which generate $(distdir)/ChangeLog in two steps.
Is it possible to simplify
gen-ChangeLog:
$(AM_V_GEN)if test -e $(srcdir)/.git; then \
LC_ALL=en_US.UTF-8 TZ=UTC0 \
$(top_srcdir)/build-aux/gitlog-to-changelog \
--srcdir=$(srcdir) > $(distdir)/ChangeLog.tmp && \
mv -f $(distdir)/ChangeLog.tmp $(distdir)/ChangeLog; \
fi
to
gen-ChangeLog:
$(AM_V_GEN)if test -e $(srcdir)/.git; then \
LC_ALL=en_US.UTF-8 TZ=UTC0 \
$(top_srcdir)/build-aux/gitlog-to-changelog \
--srcdir=$(srcdir) > $(distdir)/ChangeLog; \
fi
? If the disk is full, the former rule will package an empty ChangeLog,
whereas the latter rule will package a truncated ChangeLog.
Neither is good. What is desired, is that "make dist" fails in this situation.
That is:
gen-ChangeLog:
$(AM_V_GEN)if test -e $(srcdir)/.git; then \
LC_ALL=en_US.UTF-8 TZ=UTC0 \
$(top_srcdir)/build-aux/gitlog-to-changelog \
--srcdir=$(srcdir) > $(distdir)/ChangeLog \
|| exit 1; \
fi
And then, once we make sure that "make dist" fails, it does not matter
whether we use an intermediate file or not — because, as I wrote earlier,
the user will have to 'rm -rf' the distdir manually anyway.
2025-01-10 Bruno Haible <br...@clisp.org>
gitlog-to-changelog: Recommend more reliable Makefile rule idiom.
Reported by Basil L. Contovounesios <ba...@contovou.net>.
* doc/gitlog-to-changelog.texi: Make the gen-ChangeLog rule fail if the
ChangeLog file cannot be created or if the disk is full. Drop the use of
an intermediate file, not needed under $(distdir).
diff --git a/doc/gitlog-to-changelog.texi b/doc/gitlog-to-changelog.texi
index c58d59d8d2..9b65da9b28 100644
--- a/doc/gitlog-to-changelog.texi
+++ b/doc/gitlog-to-changelog.texi
@@ -32,8 +32,8 @@
$(AM_V_GEN)if test -e $(srcdir)/.git; then \
LC_ALL=en_US.UTF-8 TZ=UTC0 \
$(top_srcdir)/build-aux/gitlog-to-changelog \
- --srcdir=$(srcdir) > $(distdir)/ChangeLog.tmp && \
- mv -f $(distdir)/ChangeLog.tmp $(distdir)/ChangeLog; \
+ --srcdir=$(srcdir) > $(distdir)/ChangeLog \
+ || exit 1; \
fi
@end example
@@ -55,8 +55,8 @@
$(AM_V_GEN)if test -e $(srcdir)/.git; then \
$(top_srcdir)/build-aux/gitlog-to-changelog \
--srcdir=$(srcdir) --commit-timezone \
- > $(distdir)/ChangeLog.tmp && \
- mv -f $(distdir)/ChangeLog.tmp $(distdir)/ChangeLog; \
+ > $(distdir)/ChangeLog \
+ || exit 1; \
fi
@end example
@@ -100,7 +100,7 @@
--srcdir=$(srcdir) \
"$$amend_git_log" -- 'v$(gen_start_ver)~..' && \
printf '\n\nSee the source repo for older entries.\n'; \
- @} > $(distdir)/ChangeLog.tmp && \
- mv -f $(distdir)/ChangeLog.tmp $(distdir)/ChangeLog; \
+ @} > $(distdir)/ChangeLog \
+ || exit 1; \
fi
@end example
