Merge branch 'ab/pcre-v2'

Git can be built to use either v1 or v2 of the PCRE library, and so
far, the build-time configuration USE_LIBPCRE=YesPlease instructed
the build procedure to use v1, but now it means v2.  USE_LIBPCRE1
and USE_LIBPCRE2 can be used to explicitly choose which version to
use, as before.

* ab/pcre-v2:
Makefile: make USE_LIBPCRE=YesPlease mean v2, not v1
configure: detect redundant --with-libpcre & --with-libpcre1
configure: fix a regression in PCRE v1 detection

diff --combined Makefile
index a1d8775adb4b38a0340cd7d04184915f0ee65d28,449ff71f459f3580f39f1feb6d8fcda0c8e50724..180a768690e9883cd9d6f3cb68ae084cc40b9629
--- 1/Makefile
--- 2/Makefile
+++ b/Makefile
@@@ -29,10 -29,10 +29,10 @@@ all:
  # Perl-compatible regular expressions instead of standard or extended
  # POSIX regular expressions.
  #
- # Currently USE_LIBPCRE is a synonym for USE_LIBPCRE1, define
- # USE_LIBPCRE2 instead if you'd like to use version 2 of the PCRE
- # library. The USE_LIBPCRE flag will likely be changed to mean v2 by
- # default in future releases.
+ # USE_LIBPCRE is a synonym for USE_LIBPCRE2, define USE_LIBPCRE1
+ # instead if you'd like to use the legacy version 1 of the PCRE
+ # library. Support for version 1 will likely be removed in some future
+ # release of Git, as upstream has all but abandoned it.
  #
  # When using USE_LIBPCRE1, define NO_LIBPCRE1_JIT if the PCRE v1
  # library is compiled without --enable-jit. We will auto-detect
@@@ -296,12 -296,6 +296,12 @@@
  #
  # Define NO_PERL if you do not want Perl scripts or libraries at all.
  #
 +# Define NO_PERL_CPAN_FALLBACKS if you do not want to install bundled
 +# copies of CPAN modules that serve as a fallback in case the modules
 +# are not available on the system. This option is intended for
 +# distributions that want to use their packaged versions of Perl
 +# modules, instead of the fallbacks shipped with Git.
 +#
  # Define PYTHON_PATH to the path of your Python binary (often /usr/bin/python
  # but /usr/bin/python2.7 on some platforms).
  #
@@@ -1170,13 -1164,18 +1170,18 @@@ ifdef NO_LIBGEN_
        COMPAT_OBJS += compat/basename.o
  endif
  
- USE_LIBPCRE1 ?= $(USE_LIBPCRE)
+ USE_LIBPCRE2 ?= $(USE_LIBPCRE)
  
- ifneq (,$(USE_LIBPCRE1))
-       ifdef USE_LIBPCRE2
- $(error Only set USE_LIBPCRE1 (or its alias USE_LIBPCRE) or USE_LIBPCRE2, not both!)
+ ifneq (,$(USE_LIBPCRE2))
+       ifdef USE_LIBPCRE1
+ $(error Only set USE_LIBPCRE2 (or its alias USE_LIBPCRE) or USE_LIBPCRE1, not both!)
        endif
  
+       BASIC_CFLAGS += -DUSE_LIBPCRE2
+       EXTLIBS += -lpcre2-8
+ endif
+ 
+ ifdef USE_LIBPCRE1
        BASIC_CFLAGS += -DUSE_LIBPCRE1
        EXTLIBS += -lpcre
  
@@@ -1185,11 -1184,6 +1190,6 @@@ ifdef NO_LIBPCRE1_JI
  endif
  endif
  
- ifdef USE_LIBPCRE2
-       BASIC_CFLAGS += -DUSE_LIBPCRE2
-       EXTLIBS += -lpcre2-8
- endif
- 
  ifdef LIBPCREDIR
        BASIC_CFLAGS += -I$(LIBPCREDIR)/include
        EXTLIBS += -L$(LIBPCREDIR)/$(lib) $(CC_LD_DYNPATH)$(LIBPCREDIR)/$(lib)
@@@ -2310,22 -2304,14 +2310,22 @@@ po/build/locale/%/LC_MESSAGES/git.mo: p
  
  LIB_PERL := $(wildcard perl/Git.pm perl/Git/*.pm perl/Git/*/*.pm perl/Git/*/*/*.pm)
  LIB_PERL_GEN := $(patsubst perl/%.pm,perl/build/lib/%.pm,$(LIB_PERL))
 +LIB_CPAN := $(wildcard perl/FromCPAN/*.pm perl/FromCPAN/*/*.pm)
 +LIB_CPAN_GEN := $(patsubst perl/%.pm,perl/build/lib/%.pm,$(LIB_CPAN))
  
  ifndef NO_PERL
  all:: $(LIB_PERL_GEN)
 +ifndef NO_PERL_CPAN_FALLBACKS
 +all:: $(LIB_CPAN_GEN)
 +endif
 +NO_PERL_CPAN_FALLBACKS_SQ = $(subst ','\'',$(NO_PERL_CPAN_FALLBACKS))
  endif
  
  perl/build/lib/%.pm: perl/%.pm
        $(QUIET_GEN)mkdir -p $(dir $@) && \
 -      sed -e 's|@@LOCALEDIR@@|$(localedir_SQ)|g' < $< > $@
 +      sed -e 's|@@LOCALEDIR@@|$(localedir_SQ)|g' \
 +          -e 's|@@NO_PERL_CPAN_FALLBACKS@@|$(NO_PERL_CPAN_FALLBACKS_SQ)|g' \
 +      < $< > $@
  
  perl/build/man/man3/Git.3pm: perl/Git.pm
        $(QUIET_GEN)mkdir -p $(dir $@) && \