Re: [PATCH 4/4] Move initialization of Git::SVN variables into Git::SVN.

From: Junio C Hamano <gitster@pobox.com>
Date: Jul 27, 2012, 07:09 UTC
Message-ID: <7vlii51xz4.fsf@alter.siamese.dyndns.org>
In-Reply-To: <7vpq7h1z1q.fsf@alter.siamese.dyndns.org>

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

Show 29 quoted lines

> Junio C Hamano <gitster@pobox.com> writes:
>
>> t91XX series seem to fail in 'pu' with "Can't locate Git/SVN.pm in
>> @INC" for me.  I see perl/blib/lib/Git/SVN/ directory and files
>> under it, but there is no perl/blib/lib/Git/SVN.pm installed.  I see
>> Git/I18N.pm and Git/SVN/Ra.pm (and friends) mentioned in
>> perl/perl.mak generated by MakeMaker, but Git/SVN.pm does not appear
>> anywhere.
>> 
>> I think it is some interaction with other topics, as the tip of
>> ms/git-svn-pm topic that parks this series does not exhibit the
>> symptom, but it is getting late for me already, so I won't dig into
>> this further.
>
> Actually there is no difference between ms/git-svn-pm and pu in perl/
> directory. I _think_ there is some dependency missing that makes
> this sequence break:
>
> 	(in one repository)
> 	git checkout pu ;# older pu without ms/git-svn-pm
>         make ; make test
>
> 	(in another repository that shares the refs)
> 	git checkout pu
>         git merge ms/git-svn-pm
>
> 	(in the first repository)
>         git reset --hard ;# update the working tree
>         make ; make test

What was happening was that originally, pu had ms/makefile-pl but not ms/git-svn-pm. Hence, perl/Git/SVN.pm did not exist. I ran "make" and it created perl/perl.mak that does not know about Git/SVN.pm;

Then ms/git-svn-pm is merged to pu and now we have perl/Git/SVN.pm. But there is nothing in ms/makefile-pl that says on what files perl.mak depends on.

I think there needs to be a dependency in to recreate perl/perl.mak when any of the *.pm files are changed, perhaps like this.

I am not sure why perl/perl.mak is built by the top-level Makefile, instead of just using "$(MAKE) -C perl/", though...

 Makefile      | 7 +++++++
 perl/Makefile | 1 +
 2 files changed, 8 insertions(+)

diff --git a/Makefile b/Makefile
index b0b3493..e2a4ac7 100644
--- a/Makefile
+++ b/Makefile
@@ -2090,6 +2090,13 @@ $(SCRIPT_LIB) : % : %.sh GIT-SCRIPT-DEFINES
 ifndef NO_PERL
 $(patsubst %.perl,%,$(SCRIPT_PERL)): perl/perl.mak
 
+perl/perl.mak: perl/PM.stamp
+
+perl/PM.stamp: FORCE
+	$(QUIET_GEN)find perl -type f -name '*.pm' | sort >$@+ && \
+	{ cmp $@+ $@ >/dev/null 2>/dev/null || mv $@+ $@; } && \
+	$(RM) $@+
+
 perl/perl.mak: GIT-CFLAGS GIT-PREFIX perl/Makefile perl/Makefile.PL
 	$(QUIET_SUBDIR0)perl $(QUIET_SUBDIR1) PERL_PATH='$(PERL_PATH_SQ)' prefix='$(prefix_SQ)' $(@F)
 
diff --git a/perl/Makefile b/perl/Makefile
index 6ca7d47..d6f8478 100644
--- a/perl/Makefile
+++ b/perl/Makefile
@@ -20,6 +20,7 @@ clean:
 	$(RM) ppport.h
 	$(RM) $(makfile)
 	$(RM) $(makfile).old
+	$(RM) PM.stamp
 
 ifdef NO_PERL_MAKEMAKER
 instdir_SQ = $(subst ','\'',$(prefix)/lib)