Merge pull request #353 from capent/multilib

SR-2100 - Add support for multi-lib systems
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6db3850..f170fb7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,7 +31,8 @@
 include(GNUInstallDirs)
 include(SwiftSupport)
 
-set(INSTALL_LIBDIR "lib" CACHE PATH "Path where the libraries should be installed")
+set(SWIFT_LIBDIR "lib" CACHE PATH "Library folder name, defined by swift main buildscript")
+set(INSTALL_LIBDIR "${SWIFT_LIBDIR}" CACHE PATH "Path where the libraries should be installed")
 set(WITH_BLOCKS_RUNTIME "" CACHE PATH "Path to blocks runtime")
 
 include(DispatchAppleOptions)
@@ -55,7 +56,7 @@
   string(TOLOWER ${CMAKE_SYSTEM_NAME} SWIFT_OS)
   get_swift_host_arch(SWIFT_HOST_ARCH)
 
-  set(SWIFT_RUNTIME_LIBDIR ${SWIFT_TOOLCHAIN}/lib/swift/${SWIFT_OS}/${SWIFT_HOST_ARCH})
+  set(SWIFT_RUNTIME_LIBDIR ${SWIFT_TOOLCHAIN}/${SWIFT_LIBDIR}/swift/${SWIFT_OS}/${SWIFT_HOST_ARCH})
 
   add_library(swiftCore
               SHARED IMPORTED GLOBAL)