Build git from source for Mac OS X 10.9 + XCode 64-bit. I also built libpcre 8.34 to use with Git.

Makefile

.PHONY: git git-clean git-install git-install-man git-test git-uninstall

MYGIT_PREFIX=/usr/local/git
MYGIT_BUILD=git
MYGIT_BUILDOPTIONS = NO_DARWIN_PORTS=1 \
		CFLAGS="-g -O2 -Wall -arch x86_64" \
		LDFLAGS="-arch x86_64" \
		NO_GETTEXT=YesPlease \
		USE_LIBPCRE=YesPlease \
		PERLLIB_EXTRA="/Applications/Xcode.app/Contents/Developer/Library/Perl/5.16/darwin-thread-multi-2level" \
		prefix=$(MYGIT_PREFIX)

-include $(MYGIT_BUILD)/GIT-VERSION-FILE

#GIT_MAN_URL=http://www.kernel.org/pub/software/scm/git/
GIT_MAN_URL=http://git-core.googlecode.com/files/
GIT_MAN_FILE=git-manpages-$(GIT_VERSION).tar.gz

all:
	echo Read the makefile!

git:
	$(MAKE) -C $(MYGIT_BUILD) $(MYGIT_BUILDOPTIONS) all strip
	$(MAKE) -C $(MYGIT_BUILD)/contrib/credential/osxkeychain $(MYGIT_BUILDOPTIONS) all

git-clean:
	$(MAKE) -C $(MYGIT_BUILD) $(MYGIT_BUILDOPTIONS) clean
	$(MAKE) -C $(MYGIT_BUILD)/contrib/credential/osxkeychain clean

#GIT_TEST_OPTS="--verbose --debug"
git-test:
	$(MAKE) -C $(MYGIT_BUILD) $(MYGIT_BUILDOPTIONS) test

git-install:
	sudo $(MAKE) -C $(MYGIT_BUILD) $(MYGIT_BUILDOPTIONS) install
	sudo chown -R `id -un` $(MYGIT_BUILD)/git-gui/
	sudo mkdir -p $(MYGIT_PREFIX)/share/git-core/templates/info
	sudo sh -c "echo .DS_Store >> $(MYGIT_PREFIX)/share/git-core/templates/info/exclude"
	sudo mkdir -p $(MYGIT_PREFIX)/contrib/completion
	sudo cp $(MYGIT_BUILD)/contrib/completion/* $(MYGIT_PREFIX)/contrib/completion/
	sudo mkdir -p $(MYGIT_PREFIX)/contrib/credential/osxkeychain
	sudo cp $(MYGIT_BUILD)/contrib/credential/osxkeychain/git-credential-osxkeychain $(MYGIT_PREFIX)/contrib/credential/osxkeychain/

#	-sudo xattr -d com.apple.quarantine ~/Downloads/$(GIT_MAN_FILE)
git-install-man:
	test "$(GIT_VERSION)" -a "You need to build git first to create $(MYGIT_BUILD)/GIT-VERSION-FILE (or set GIT_VERSION make variable)"
	curl --fail -o ~/Downloads/$(GIT_MAN_FILE) $(GIT_MAN_URL)$(GIT_MAN_FILE)
	sudo rm -rf $(MYGIT_PREFIX)/share/man
	sudo mkdir -p $(MYGIT_PREFIX)/share/man
	sudo tar -xvo -C $(MYGIT_PREFIX)/share/man -f ~/Downloads/$(GIT_MAN_FILE)
	sudo chmod +rx $(MYGIT_PREFIX)/share/man
	rm -f ~/Downloads/$(GIT_MAN_FILE)

git-uninstall:
	sudo rm -rf $(MYGIT_PREFIX)

I use this Makefile to build git from source for my Mac.