static: use pkg-config exclusively when using it #445

2018-06-28T12:26:21-05:00

rmg commented

2018-06-28 12:26:21 -05:00

(Migrated from github.com)

When using the static linking option on platforms that use pkg-config,
use ONLY pkg-config to get the CFLAGS and LDFLAGS. This prevents pulling
in dependencies and flags for any non-vendored version that may be
present on the host.

The main practical effect of this is that if someone doesn't need/want
any sort of remote access support at all they can completely disable
libcurl, libssh2, libssl, etc and produce a smaller/simpler binary and
greatly simplify their build-time dependencies. When done properly, the
generated pkg-config file will tell cgo everything it needs to know.

This also prevents confusion if there is a system copy of libgit2 that
is being given priority over the vendored build.

When using the static linking option on platforms that use pkg-config, use ONLY pkg-config to get the CFLAGS and LDFLAGS. This prevents pulling in dependencies and flags for any non-vendored version that may be present on the host. The main practical effect of this is that if someone doesn't need/want any sort of remote access support at all they can completely disable libcurl, libssh2, libssl, etc and produce a smaller/simpler binary and greatly simplify their build-time dependencies. When done properly, the generated pkg-config file will tell cgo everything it needs to know. This also prevents confusion if there is a system copy of libgit2 that is being given priority over the vendored build.

rmg commented

2018-06-28 12:36:22 -05:00

(Migrated from github.com)

This patch was required to be able to do the following in my builds:

LIBGIT2 := vendor/gopkg.in/libgit2/git2go.v27/vendor/libgit2
LIBGIT2PC := $(LIBGIT2)/build/libgit2.pc

my_cmd: cmd/my_cmd/*.go $(LIBGIT2PC)
	go build -o $@ --tags "static" ./cmd/my_cmd

$(LIBGIT2)/CMakeLists.txt:
	git submodule update --init $(@D)

$(LIBGIT2PC): $(LIBGIT2)/CMakeLists.txt
	mkdir -p $(@D) $(LIBGIT2)/install/lib
	cd $(@D) && \
		cmake -DTHREADSAFE=ON \
			-DBUILD_CLAR=OFF \
			-DUSE_SSH=OFF \
			-DUSE_HTTPS=OFF \
			-DCURL=OFF \
			-DBUILD_SHARED_LIBS=OFF \
			-DCMAKE_C_FLAGS=-fPIC \
			-DCMAKE_INSTALL_PREFIX=../install \
			-DCMAKE_BUILD_TYPE="MinSizeRel" \
		.. && \
	  cmake --build . && \
	  make install

This patch was required to be able to do the following in my builds: ``` LIBGIT2 := vendor/gopkg.in/libgit2/git2go.v27/vendor/libgit2 LIBGIT2PC := $(LIBGIT2)/build/libgit2.pc my_cmd: cmd/my_cmd/*.go $(LIBGIT2PC) go build -o $@ --tags "static" ./cmd/my_cmd $(LIBGIT2)/CMakeLists.txt: git submodule update --init $(@D) $(LIBGIT2PC): $(LIBGIT2)/CMakeLists.txt mkdir -p $(@D) $(LIBGIT2)/install/lib cd $(@D) && \ cmake -DTHREADSAFE=ON \ -DBUILD_CLAR=OFF \ -DUSE_SSH=OFF \ -DUSE_HTTPS=OFF \ -DCURL=OFF \ -DBUILD_SHARED_LIBS=OFF \ -DCMAKE_C_FLAGS=-fPIC \ -DCMAKE_INSTALL_PREFIX=../install \ -DCMAKE_BUILD_TYPE="MinSizeRel" \ .. && \ cmake --build . && \ make install ```

lhchavez (Migrated from github.com) reviewed 2018-07-07 18:12:11 -05:00

script/build-libgit2-static.sh

lhchavez (Migrated from github.com) commented

2018-07-07 18:12:10 -05:00

You can use cmake --build . --target install as in f463379110/script/cibuild.sh (L27)

You can use `cmake --build . --target install` as in https://github.com/libgit2/libgit2/blob/f4633791104fa5be75115fd4c7fab0c097da345e/script/cibuild.sh#L27