If we have never seen attr 'X' in any .gitattributes file we have
examined so far, we can be sure that 'X' is not defined. So no need to
go over all the attr stack to look for attr 'X'. This is the purpose
behind this new field maybe_real.

This optimization breaks down if macros are involved because we can't
know for sure what macro would expand to 'X' at attr parsing time. But
if we go the pessimistic way and assume all macros are expanded, we hit
the builtin "binary" macro. At least the "diff" attr defined in this
macro will disable this optimization for git-grep. So we wait until
any attr lines _may_ reference to a macro before we turn this off.

In git.git, this reduces the number of fill_one() call for "git grep
abcdefghi" from ~5348 to 2955. The optimization stops when it reads
t/.gitattributes, which uses 'binary' macro. We could probably reduce
it further by limiting the 'binary' reference to t/ and subdirs only
in this case.

"git grep" is actually a good example to justify this patch. The
command checks "diff" attribute on every file. People usually don't
define this attribute. But they pay the attr lookup penalty anyway
without this patch, proportional to the number of attr lines they have
in repo.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Keep track of all recognized macros in the new "maybe_macro" field.
If this field is true, it _may_ be a macro (depending on what's in the
current attr stack). But if the field is false, it's definitely not a
macro, no need to go through the whole attr stack in macroexpand_one()
to search for one.

Without this, "git grep abcdefghi" on git.git hits the inner loop in
macroexpand_one() 2481 times. With this, it's 66 times.

Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Signed-off-by: Junio C Hamano <gitster@pobox.com>

The build procedure did not bother fixing perl and python scripts
when NO_PERL and NO_PYTHON build-time configuration changed.

* jk/rebuild-perl-scripts-with-no-perl-seting-change:
  Makefile: have python scripts depend on NO_PYTHON setting
  Makefile: simplify by using SCRIPT_{PERL,SH}_GEN macros
  Makefile: have perl scripts depend on NO_PERL setting

Some tests that depend on perl lacked PERL prerequisite to protect
them, breaking build with NO_PERL configuration.

* jk/no-perl-tests:
  t960[34]: mark cvsimport tests as requiring perl
  t0090: mark add-interactive test with PERL prerequisite

"Everyday" document had a broken link.

* po/everyday-doc:
  Documentation: change "gitlink" typo in git-push

Git 2.0 was supposed to make the "simple" mode for the default of
"git push", but it didn't.

* jk/push-simple:
  push: truly use "simple" as default, not "upstream"

"git init" (hence "git clone") initialized the per-repository
configuration file .git/config with x-bit by mistake.

* mh/config-flip-xbit-back-after-checking:
  create_default_files(): don't set u+x bit on $GIT_DIR/config

"gitweb" used to depend on a behaviour that was deprecated by recent
CGI.pm.

* jk/gitweb-with-newer-cgi-multi-param:
  gitweb: hack around CGI's list-context param() handling