[PATCH 1/3] Move git_version_string to help.c before diff changes

["Zbigniew Jędrzejewski-Szmek" <zbyszek@in.waw.pl>]

git_version_string lives in git.c. When diff.c starts to use functions
from help.c, which in turn use git_version_string, linking against
libgit.a will fail. This is because git_version_string is physically
located in git.o, and this object file is not part of libgit.a. One
option would be to add git.o to libgit.a, but git.o is biggish. The
second, better option is to move git_version_string to somewhere where
it'll become part of libgit.a. This variable is only used in a couple
of places, help.c being one of them, so it let's move
git_version_string from git.c to help.c. The git binary is linked with
help.o, so it is not affected by this move.

Without this change the next commit would fail with:
$ gcc  -g -O0 -I. -DUSE_LIBPCRE  -DHAVE_PATHS_H -DHAVE_DEV_TTY -DSHA1_HEADER='<openssl/sha.h>'  -DNO_STRLCPY -DNO_MKSTEMPS -o git-daemon   daemon.o libgit.a xdiff/lib.a  -lpcre -lz  -lcrypto -lpthread
libgit.a(help.o): In function `cmd_version':
/home/zbyszek/git/git/help.c:435: undefined reference to `git_version_string'

Signed-off-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
---
 Makefile |    5 +++--
 git.c    |    2 --
 help.c   |    2 ++
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/Makefile b/Makefile
index 4817157..ccafb95 100644
--- a/Makefile
+++ b/Makefile
@@ -1890,7 +1890,7 @@ strip: $(PROGRAMS) git$X
 	$(STRIP) $(STRIP_OPTS) $(PROGRAMS) git$X
 
 git.o: common-cmds.h
-git.sp git.s git.o: EXTRA_CPPFLAGS = -DGIT_VERSION='"$(GIT_VERSION)"' \
+git.sp git.s git.o: EXTRA_CPPFLAGS = \
 	'-DGIT_HTML_PATH="$(htmldir_SQ)"' \
 	'-DGIT_MAN_PATH="$(mandir_SQ)"' \
 	'-DGIT_INFO_PATH="$(infodir_SQ)"'
@@ -1899,7 +1899,8 @@ git$X: git.o GIT-LDFLAGS $(BUILTIN_OBJS) $(GITLIBS)
 	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ git.o \
 		$(BUILTIN_OBJS) $(ALL_LDFLAGS) $(LIBS)
 
-help.sp help.o: common-cmds.h
+help.o: common-cmds.h
+help.sp help.o: EXTRA_CPPFLAGS = -DGIT_VERSION='"$(GIT_VERSION)"'
 
 builtin/help.sp builtin/help.o: common-cmds.h
 builtin/help.sp builtin/help.s builtin/help.o: EXTRA_CPPFLAGS = \
diff --git a/git.c b/git.c
index 3805616..a24a0fd 100644
--- a/git.c
+++ b/git.c
@@ -256,8 +256,6 @@ static int handle_alias(int *argcp, const char ***argv)
 	return ret;
 }
 
-const char git_version_string[] = GIT_VERSION;
-
 #define RUN_SETUP		(1<<0)
 #define RUN_SETUP_GENTLY	(1<<1)
 #define USE_PAGER		(1<<2)
diff --git a/help.c b/help.c
index cbbe966..bc15066 100644
--- a/help.c
+++ b/help.c
@@ -409,6 +409,8 @@ const char *help_unknown_cmd(const char *cmd)
 	exit(1);
 }
 
+const char git_version_string[] = GIT_VERSION;
+
 int cmd_version(int argc, const char **argv, const char *prefix)
 {
 	printf("git version %s\n", git_version_string);
-- 
1.7.9.263.g4be11.dirty