Makefile: do not force unneeded recompilation upon GIT_VERSION changes

diff --git a/Makefile b/Makefile
index 28517f4c3f01ee3b854439033f7143763a8f62cf..d45f3dcf6214f8a60f3e636d1c5067d273551f0c 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -212,11 +212,11 @@ LIB_OBJS = \
        blob.o commit.o connect.o csum-file.o cache-tree.o base85.o \
        date.o diff-delta.o entry.o exec_cmd.o ident.o lockfile.o \
        object.o pack-check.o patch-delta.o path.o pkt-line.o \
-       quote.o read-cache.o refs.o run-command.o dir.o \
+       quote.o read-cache.o refs.o run-command.o dir.o object-refs.o \
        server-info.o setup.o sha1_file.o sha1_name.o strbuf.o \
        tag.o tree.o usage.o config.o environment.o ctype.o copy.o \
        fetch-clone.o revision.o pager.o tree-walk.o xdiff-interface.o \
-       $(DIFF_OBJS)
+       alloc.o $(DIFF_OBJS)
 
 BUILTIN_OBJS = \
        builtin-log.o builtin-help.o builtin-count.o builtin-diff.o builtin-push.o \
@@ -464,6 +464,7 @@ DESTDIR_SQ = $(subst ','\'',$(DESTDIR))
 bindir_SQ = $(subst ','\'',$(bindir))
 gitexecdir_SQ = $(subst ','\'',$(gitexecdir))
 template_dir_SQ = $(subst ','\'',$(template_dir))
+prefix_SQ = $(subst ','\'',$(prefix))
 
 SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))
 PERL_PATH_SQ = $(subst ','\'',$(PERL_PATH))
@@ -471,7 +472,6 @@ PYTHON_PATH_SQ = $(subst ','\'',$(PYTHON_PATH))
 GIT_PYTHON_DIR_SQ = $(subst ','\'',$(GIT_PYTHON_DIR))
 
 ALL_CFLAGS += -DSHA1_HEADER='$(SHA1_HEADER_SQ)' $(COMPAT_CFLAGS)
-ALL_CFLAGS += -DDEFAULT_GIT_TEMPLATE_DIR='"$(template_dir_SQ)"'
 LIB_OBJS += $(COMPAT_OBJS)
 export prefix TAR INSTALL DESTDIR SHELL_PATH template_dir
 ### Build rules
@@ -484,7 +484,7 @@ all:
 strip: $(PROGRAMS) git$X
        $(STRIP) $(STRIP_OPTS) $(PROGRAMS) git$X
 
-git$X: git.c common-cmds.h $(BUILTIN_OBJS) $(GITLIBS)
+git$X: git.c common-cmds.h $(BUILTIN_OBJS) $(GITLIBS) GIT-CFLAGS
        $(CC) -DGIT_VERSION='"$(GIT_VERSION)"' \
                $(ALL_CFLAGS) -o $@ $(filter %.c,$^) \
                $(BUILTIN_OBJS) $(ALL_LDFLAGS) $(LIBS)
@@ -516,7 +516,7 @@ $(patsubst %.perl,%,$(SCRIPT_PERL)) : % : %.perl
        chmod +x $@+
        mv $@+ $@
 
-$(patsubst %.py,%,$(SCRIPT_PYTHON)) : % : %.py
+$(patsubst %.py,%,$(SCRIPT_PYTHON)) : % : %.py GIT-CFLAGS
        rm -f $@ $@+
        sed -e '1s|#!.*python|#!$(PYTHON_PATH_SQ)|' \
            -e 's|@@GIT_PYTHON_PATH@@|$(GIT_PYTHON_DIR_SQ)|g' \
@@ -540,19 +540,21 @@ git$X git.spec \
        $(patsubst %.py,%,$(SCRIPT_PYTHON)) \
        : GIT-VERSION-FILE
 
-%.o: %.c
+%.o: %.c GIT-CFLAGS
        $(CC) -o $*.o -c $(ALL_CFLAGS) $<
 %.o: %.S
        $(CC) -o $*.o -c $(ALL_CFLAGS) $<
 
-exec_cmd.o: exec_cmd.c
+exec_cmd.o: exec_cmd.c GIT-CFLAGS
        $(CC) -o $*.o -c $(ALL_CFLAGS) '-DGIT_EXEC_PATH="$(gitexecdir_SQ)"' $<
+builtin-init-db.o: builtin-init-db.c GIT-CFLAGS
+       $(CC) -o $*.o -c $(ALL_CFLAGS) -DDEFAULT_GIT_TEMPLATE_DIR='"$(template_dir_SQ)"' $<
 
-http.o: http.c
+http.o: http.c GIT-CFLAGS
        $(CC) -o $*.o -c $(ALL_CFLAGS) -DGIT_USER_AGENT='"git/$(GIT_VERSION)"' $<
 
 ifdef NO_EXPAT
-http-fetch.o: http-fetch.c http.h
+http-fetch.o: http-fetch.c http.h GIT-CFLAGS
        $(CC) -o $*.o -c $(ALL_CFLAGS) -DNO_EXPAT $<
 endif
 
@@ -609,6 +611,17 @@ tags:
        rm -f tags
        find . -name '*.[hcS]' -print | xargs ctags -a
 
+### Detect prefix changes
+TRACK_CFLAGS = $(subst ','\'',$(ALL_CFLAGS)):$(GIT_PYTHON_DIR_SQ):\
+             $(bindir_SQ):$(gitexecdir_SQ):$(template_dir_SQ):$(prefix_SQ)
+
+GIT-CFLAGS: .FORCE-GIT-CFLAGS
+       @FLAGS='$(TRACK_CFLAGS)'; \
+           if test x"$$FLAGS" != x"`cat GIT-CFLAGS 2>/dev/null`" ; then \
+               echo 1>&2 "    * new build flags or prefix"; \
+               echo "$$FLAGS" >GIT-CFLAGS; \
+            fi
+
 ### Testing rules
 
 # GNU make supports exporting all variables by "export" without parameters.
@@ -711,10 +724,10 @@ clean:
        $(MAKE) -C Documentation/ clean
        $(MAKE) -C templates clean
        $(MAKE) -C t/ clean
-       rm -f GIT-VERSION-FILE
+       rm -f GIT-VERSION-FILE GIT-CFLAGS
 
 .PHONY: all install clean strip
-.PHONY: .FORCE-GIT-VERSION-FILE TAGS tags
+.PHONY: .FORCE-GIT-VERSION-FILE TAGS tags .FORCE-GIT-CFLAGS
 
 ### Check documentation
 #