now new branches' job hardlinks the same dir from master (#321)

.gitlab-ci.yml

@@ -36,9 +36,17 @@ variables:
     - rustup show
     - bash --version
     - mkdir -p ${CARGO_HOME}; touch ${CARGO_HOME}/config
-    - mkdir -p ${CARGO_TARGET_DIR}
     # global RUSTFLAGS overrides the linker args so this way is better to pass the flags
     - printf '[build]\nrustflags = ["-C", "link-dead-code"]\n' | tee ${CARGO_HOME}/config
+    # if there is no directory for this $CI_COMMIT_REF_NAME/$CI_JOB_NAME
+    # create such directory and
+    # create hardlinks recursively of all the files from the master/$CI_JOB_NAME if it exists
+    - if [[ ! -d $CARGO_TARGET_DIR ]]; then
+        mkdir -p /ci-cache/${CI_PROJECT_NAME}/targets/${CI_COMMIT_REF_NAME};
+        cp -al /ci-cache/${CI_PROJECT_NAME}/targets/${CI_DEFAULT_BRANCH}/${CI_JOB_NAME}
+          /ci-cache/${CI_PROJECT_NAME}/targets/${CI_COMMIT_REF_NAME} ||
+          echo "_____No such target dir, proceeding from scratch_____";
+      fi
     - sccache -s
   only:
     - master