Remove support for v1 of the PCRE library

Remove support for using version 1 of the PCRE library. Its use has
been discouraged by upstream for a long time, and it's in a
bugfix-only state.

Anyone who was relying on v1 in particular got a nudge to move to v2
in e6c531b808 (Makefile: make USE_LIBPCRE=YesPlease mean v2, not v1,
2018-03-11), which was first released as part of v2.18.0.

With this the LIBPCRE2 test prerequisites is redundant to PCRE. But
I'm keeping it for self-documentation purposes, and to avoid conflict
with other in-flight PCRE patches.

I'm also not changing all of our own "pcre2" names to "pcre", i.e. the
inverse of 6d4b5747f0 (grep: change internal *pcre* variable &
function names to be *pcre1*, 2017-05-25). I don't see the point, and
it makes the history/blame harder to read. Maybe if there's ever a
PCRE v3...

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 7 insertions, 25 deletions

diff --git a/Makefile b/Makefile
index 4edfda3e00..cd0ff9a040 100644
--- a/Makefile
+++ b/Makefile
@@ -29,18 +29,11 @@ all::
 # Perl-compatible regular expressions instead of standard or extended
 # POSIX regular expressions.
 #
-# 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 you want to
-# disable JIT even if supported by your library.
+# Only libpcre version 2 is supported. USE_LIBPCRE2 is a synonym for
+# USE_LIBPCRE, support for the old USE_LIBPCRE1 has been removed.
 #
 # Define LIBPCREDIR=/foo/bar if your PCRE header and library files are
-# in /foo/bar/include and /foo/bar/lib directories. Which version of
-# PCRE this points to determined by the USE_LIBPCRE1 and USE_LIBPCRE2
-# variables.
+# in /foo/bar/include and /foo/bar/lib directories.
 #
 # Define HAVE_ALLOCA_H if you have working alloca(3) defined in that header.
 #
@@ -1359,26 +1352,17 @@ ifdef NO_LIBGEN_H
 	COMPAT_OBJS += compat/basename.o
 endif
 
+ifdef USE_LIBPCRE1
+$(error The USE_LIBPCRE1 build option has been removed, use version 2 with USE_LIBPCRE)
+endif
+
 USE_LIBPCRE2 ?= $(USE_LIBPCRE)
 
 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
-
-ifdef NO_LIBPCRE1_JIT
-	BASIC_CFLAGS += -DNO_LIBPCRE1_JIT
-endif
-endif
-
 ifdef LIBPCREDIR
 	BASIC_CFLAGS += -I$(LIBPCREDIR)/include
 	EXTLIBS += -L$(LIBPCREDIR)/$(lib) $(CC_LD_DYNPATH)$(LIBPCREDIR)/$(lib)
@@ -2726,9 +2710,7 @@ GIT-BUILD-OPTIONS: FORCE
 	@echo TAR=\''$(subst ','\'',$(subst ','\'',$(TAR)))'\' >>$@+
 	@echo NO_CURL=\''$(subst ','\'',$(subst ','\'',$(NO_CURL)))'\' >>$@+
 	@echo NO_EXPAT=\''$(subst ','\'',$(subst ','\'',$(NO_EXPAT)))'\' >>$@+
-	@echo USE_LIBPCRE1=\''$(subst ','\'',$(subst ','\'',$(USE_LIBPCRE1)))'\' >>$@+
 	@echo USE_LIBPCRE2=\''$(subst ','\'',$(subst ','\'',$(USE_LIBPCRE2)))'\' >>$@+
-	@echo NO_LIBPCRE1_JIT=\''$(subst ','\'',$(subst ','\'',$(NO_LIBPCRE1_JIT)))'\' >>$@+
 	@echo NO_PERL=\''$(subst ','\'',$(subst ','\'',$(NO_PERL)))'\' >>$@+
 	@echo NO_PTHREADS=\''$(subst ','\'',$(subst ','\'',$(NO_PTHREADS)))'\' >>$@+
 	@echo NO_PYTHON=\''$(subst ','\'',$(subst ','\'',$(NO_PYTHON)))'\' >>$@+