Merge pull request #4528 from itaiferber/pr-foundation-3.0-integration

[DO NOT MERGE YET] Cherry-pick commits required for swift-3.0-branch Foundation integration

Author: tkremenek

utils/build-presets.ini

@@ -644,11 +644,13 @@ test
 validation-test
 long-test
 foundation
+libdispatch
 lit-args=-v
 
 dash-dash
 
 install-foundation
+install-libdispatch
 reconfigure
 
 # Ubuntu 16.04 preset for backwards compat and future customizations.
@@ -730,6 +732,7 @@ llbuild
 swiftpm
 xctest
 foundation
+libdispatch
 dash-dash
 
 [preset: buildbot_incremental_linux,long_test]

utils/build-script-impl

@@ -2390,7 +2390,8 @@ for host in "${ALL_HOSTS[@]}"; do
                 SWIFTC_BIN="$(build_directory_bin ${LOCAL_HOST} swift)/swiftc"
                 LLVM_BIN="$(build_directory_bin ${LOCAL_HOST} llvm)"
 
-                if [[ ! -f "${LIBDISPATCH_BUILD_DIR}"/config.status ]]; then
+                if [[ "${RECONFIGURE}" || ! -f "${LIBDISPATCH_BUILD_DIR}"/config.status ]]; then
+                    echo "Reconfiguring libdispatch"
                     # First time building; need to run autotools and configure
                     if [[ "$LIBDISPATCH_BUILD_TYPE" == "Release" ]] ; then
                         dispatch_build_variant_arg="release"
@@ -2407,7 +2408,8 @@ for host in "${ALL_HOSTS[@]}"; do
                             "${LIBDISPATCH_SOURCE_DIR}"/configure --with-swift-toolchain="${SWIFT_BUILD_PATH}" \
                             --with-build-variant=$dispatch_build_variant_arg \
                             --prefix="$(get_host_install_destdir ${host})$(get_host_install_prefix ${host})"
-
+                else
+                    echo "Skipping reconfiguration of libdispatch"
                 fi
                 with_pushd "${LIBDISPATCH_BUILD_DIR}" \
                     call make