Re: [PATCH 6/6] Simplify and improve safety of bootstrap process.

[Ralf Wildenhues]

* Gary V. Vaughan wrote on Tue, Aug 31, 2010 at 08:43:20AM CEST:
> * Makefile.am (bootstrap_files): List files that need to be
> generated at bootstrap time before `./configure && make' can
> work.  It turns out that this is considerably fewer files than we
> had thought necessary previously.
> (bootstrap-deps-prep): Ensure minimum set of required substitution
> variables are non-empty.
> (bootstrap-deps): Depend on `bootstrap' files.
> * bootstrap (Generate bootstrap dependencies): Now that
> `Makefile.am' is entirely responsible for rebuilding files at
> bootstrap time, we need only specify the new `bootstrap-deps'
> target, and supply values for the substitutions checked by
> `bootstrap-deps-prep'.

This is a fairly nice cleanup that I think is valuable to redo without
the other rejected patches.  Please resubmit with nit below addressed,
and I will approve it then after looking over once more.

Thanks,
Ralf

> --- a/Makefile.am
> +++ b/Makefile.am

> +## Document the make macros that are needed to build bootstrap-deps
> +## dependencies when called from `bootstrap' (developer's machine),
> +## where the Makefile.am is fed to make in its raw format before
> +## `configure' has found the correct values (on the build machine).
> +bootstrap_files = \
> +    $(auxdir)/ltmain.sh \
> +    $(m4dir)/ltversion.m4 \
> +    libltdl/Makefile.am
> +
> +.PHONY: bootstrap-deps bootstrap-deps-prep
> +bootstrap-deps: bootstrap-deps-prep $(bootstrap_files)
> +bootstrap-deps-prep:
> +## The following variables are substituted by `bootstrap-dep-preps'
> +     @test -n "$(srcdir)" \
> +        || echo "ERROR: don't call $(MAKE) with srcdir unset."
> +     @test -n "$(M4SH)" \
> +         || echo "ERROR: don't call $(MAKE) with M4SH unset."
> +     @test -n "$(PACKAGE)" \
> +         || echo "ERROR: don't call $(MAKE) with PACKAGE unset."
> +     @test -n "$(PACKAGE_BUGREPORT)" \
> +         || echo "ERROR: don't call $(MAKE) with PACKAGE_BUGREPORT unset."
> +     @test -n "$(PACKAGE_NAME)" \
> +         || echo "ERROR: don't call $(MAKE) with PACKAGE_NAME unset."
> +     @test -n "$(PACKAGE_URL)" \
> +         || echo "ERROR: don't call $(MAKE) with PACKAGE_URL unset."
> +     @test -n "$(SED)" \
> +         || echo "ERROR: don't call $(MAKE) with SED unset."
> +     @test -n "$(VERSION)" \
> +         || echo "ERROR: don't call $(MAKE) with VERSION unset."
> +     rm -f $(bootstrap_files)

It would be nice if this rule would actually error out (i.e., have
nonzero exit status) if any of the variables were unset.

> -test -f clcommit.m4sh && $MAKE -f Makefile.maint ./commit \
> -    srcdir=. top_srcdir=. PACKAGE="$package" VERSION="$version" \
> -    M4SH="$AUTOM4TE -l m4sh" \
> -    SED="$SED" GREP="$GREP" FGREP="$FGREP" EGREP="$EGREP" LN_S="$LN_S"
> +func_show_eval "$MAKE bootstrap-deps  \
> +M4SH='$AUTOM4TE --language=m4sh' PACKAGE='$package' \
> +PACKAGE_BUGREPORT='$package_bugreport' PACKAGE_NAME='$package_name' \
> +PACKAGE_URL='$package_url' SED='$SED' srcdir=. VERSION='$version'"

For bootstrap, the func_show_eval from the rejected patch is probably
gotten just as easily by just 'set -x'; besides the fact that using eval
on this string is wrong.