diff --git a/README.md b/README.md
index f821113980762..6829d9a08df3b 100644
--- a/README.md
+++ b/README.md
@@ -58,7 +58,7 @@ For OS X, you need [the latest Xcode](https://developer.apple.com/xcode/download
 
 For Ubuntu, you'll need the following development dependencies:
 
-    sudo apt-get install git cmake ninja-build clang python uuid-dev libicu-dev icu-devtools libbsd-dev libedit-dev libxml2-dev libsqlite3-dev swig libpython-dev libncurses5-dev pkg-config
+    sudo apt-get install git cmake ninja-build clang python uuid-dev libicu-dev icu-devtools libbsd-dev libedit-dev libxml2-dev libsqlite3-dev swig libpython-dev libncurses5-dev pkg-config libblocksruntime-dev
 
 **Note:** LLDB currently requires at least `swig-1.3.40` but will successfully build
 with version 2 shipped with Ubuntu.
diff --git a/tools/SourceKit/CMakeLists.txt b/tools/SourceKit/CMakeLists.txt
index d2ffbfd219dad..7ecd8e8a6ee9b 100644
--- a/tools/SourceKit/CMakeLists.txt
+++ b/tools/SourceKit/CMakeLists.txt
@@ -84,6 +84,11 @@ function(add_sourcekit_default_compiler_flags target)
     ANALYZE_CODE_COVERAGE "${analyze_code_coverage}"
     RESULT_VAR_NAME link_flags)
 
+  if("${CMAKE_SYSTEM_NAME}" STREQUAL "Linux")
+    list(APPEND c_compile_flags "-fblocks")
+    list(APPEND link_flags "-lBlocksRuntime")
+  endif()
+
   # Convert variables to space-separated strings.
   _list_escape_for_shell("${c_compile_flags}" c_compile_flags)
   _list_escape_for_shell("${link_flags}" link_flags)