diff options
| author | Patrick Steinhardt <psteinhardt@gitlab.com> | 2021-02-17 12:57:34 +0300 |
|---|---|---|
| committer | Patrick Steinhardt <psteinhardt@gitlab.com> | 2021-02-17 13:25:19 +0300 |
| commit | 094292fc51484af1400be75b7bb1431157cda8b0 (patch) | |
| tree | 5225e0a1ccde105e7a2576de1e523065e0817725 | |
| parent | c75c02f52decfb1f89e30e15420d29207ccfa3ca (diff) | |
Makefile: Rebuild git and libgit2 only if their version changes
Currently, we just recompile both git and libgit2 whenever the Makefile
changes. This has been a good-enough proxy for whether their version has
potentially changed, but it's still kind of inefficient: in most cases,
a Makefile change will probably not require a rebuild at all.
This commit introduces much more granualar check by writing the
currently compiled and installed version of the given dependency into
its own file. This file gets updated on each run, but only if its
current version doesn't match the requested version.
This has two benefits: first, one can now change the Makefile without
causing needless rebuilds of both git and libgit2. And second, one can
now execute `make GIT_VERSION=something` via the command line, which
correctly causes rebuilds if the git version is not what we currently
have.
| -rw-r--r-- | Makefile | 15 |
1 files changed, 12 insertions, 3 deletions
@@ -394,12 +394,21 @@ ${BUILD_DIR}/tools: | ${BUILD_DIR} ${BUILD_DIR}/Makefile.sha256: Makefile | ${BUILD_DIR} ${Q}sha256sum -c $@ >/dev/null 2>&1 || >$@ sha256sum Makefile -${BUILD_DIR}/git_full_bins.tgz: ${BUILD_DIR}/Makefile.sha256 +# This is in the same spirit as the Makefile.sha256 optimization: we want to +# rebuild only if the dependency's version changes. The dependency on the phony +# target is required to always rebuild these targets. +.PHONY: dependency-version +${BUILD_DIR}/libgit2.version: dependency-version | ${BUILD_DIR} + ${Q}[ x"$$(cat "$@" 2>/dev/null)" = x"${LIBGIT2_VERSION}" ] || >$@ echo -n "${LIBGIT2_VERSION}" +${BUILD_DIR}/git.version: dependency-version | ${BUILD_DIR} + ${Q}[ x"$$(cat "$@" 2>/dev/null)" = x"${GIT_VERSION}" ] || >$@ echo -n "${GIT_VERSION}" + +${BUILD_DIR}/git_full_bins.tgz: ${BUILD_DIR}/git.version curl -o $@.tmp --silent --show-error -L ${GIT_BINARIES_URL} ${Q}printf '${GIT_BINARIES_HASH} $@.tmp' | sha256sum -c - ${Q}mv $@.tmp $@ -${LIBGIT2_INSTALL_DIR}/lib/libgit2.a: ${BUILD_DIR}/Makefile.sha256 +${LIBGIT2_INSTALL_DIR}/lib/libgit2.a: ${BUILD_DIR}/libgit2.version ${Q}if ! [ -d "${LIBGIT2_SOURCE_DIR}" ]; then \ ${GIT} clone --depth 1 --branch ${LIBGIT2_VERSION} --quiet ${LIBGIT2_REPO_URL} ${LIBGIT2_SOURCE_DIR}; \ elif ! git -C "${LIBGIT2_SOURCE_DIR}" rev-parse --quiet --verify ${LIBGIT2_VERSION}^{tree} >/dev/null; then \ @@ -412,7 +421,7 @@ ${LIBGIT2_INSTALL_DIR}/lib/libgit2.a: ${BUILD_DIR}/Makefile.sha256 go install -a github.com/libgit2/git2go/${GIT2GO_VERSION} ifeq (${GIT_USE_PREBUILT_BINARIES},) -${GIT_INSTALL_DIR}/bin/git: ${BUILD_DIR}/Makefile.sha256 +${GIT_INSTALL_DIR}/bin/git: ${BUILD_DIR}/git.version ${Q}if ! [ -d "${GIT_SOURCE_DIR}" ]; then \ ${GIT} clone --depth 1 --branch ${GIT_VERSION} --quiet ${GIT_REPO_URL} ${GIT_SOURCE_DIR}; \ elif ! git -C "${GIT_SOURCE_DIR}" rev-parse --quiet --verify ${GIT_VERSION}^{tree} >/dev/null; then \ |