Index: utils/release/test-release.sh
===================================================================
--- utils/release/test-release.sh
+++ utils/release/test-release.sh
@@ -18,7 +18,8 @@
     MAKE=make
 fi
 
-projects="llvm cfe compiler-rt libcxx libcxxabi test-suite clang-tools-extra libunwind"
+# Basic projects, always built
+projects="llvm cfe clang-tools-extra"
 
 # Base SVN URL for the sources.
 Base_url="http://llvm.org/svn/llvm-project"
@@ -32,6 +33,9 @@
 do_debug="no"
 do_asserts="no"
 do_compare="yes"
+do_rt="yes"
+do_libs="yes"
+do_test_suite="yes"
 BuildDir="`pwd`"
 use_autoconf="no"
 ExtraConfigureFlags=""
@@ -55,6 +59,9 @@
     echo " -use-autoconf        Use autoconf instead of cmake"
     echo " -svn-path DIR        Use the specified DIR instead of a release."
     echo "                      For example -svn-path trunk or -svn-path branches/release_37"
+    echo " -no-rt               Disable check-out & build Compiler-RT"
+    echo " -no-libs             Disable check-out & build libcxx/libcxxabi/libunwind"
+    echo " -no-test-suite       Disable check-out & build test-suite"
 }
 
 if [ `uname -s` = "Darwin" ]; then
@@ -123,6 +130,15 @@
         -use-autoconf | --use-autoconf )
             use_autoconf="yes"
             ;;
+        -no-rt )
+            do_rt="no"
+            ;;
+        -no-libs )
+            do_libs="no"
+            ;;
+        -no-test-suite )
+            do_test_suite="no"
+            ;;
         -help | --help | -h | --h | -\? )
             usage
             exit 0
@@ -167,6 +183,17 @@
     NumJobs=3
 fi
 
+# Update projects list
+if [ $do_rt = "yes" ]; then
+  projects="$projects compiler-rt"
+fi
+if [ $do_libs = "yes" ]; then
+  projects="$projects libcxx libcxxabi libunwind"
+fi
+if [ $do_test_suite = "yes" ]; then
+  projects="$projects test-suite"
+fi
+
 # Go to the build directory (may be different from CWD)
 BuildDir=$BuildDir/$RC
 mkdir -p $BuildDir
@@ -215,6 +242,10 @@
     check_valid_urls
 
     for proj in $projects ; do
+        if [ -d $proj.src ]; then
+          echo "# Reusing $proj $Release-$RC sources"
+          continue
+        fi
         echo "# Exporting $proj $Release-$RC sources"
         if ! svn export -q $Base_url/$proj/$ExportBranch $proj.src ; then
             echo "error: failed to export $proj project"
@@ -232,19 +263,19 @@
         ln -s ../../../../clang-tools-extra.src extra
     fi
     cd $BuildDir/llvm.src/projects
-    if [ ! -h test-suite ]; then
+    if [ -d $BuildDir/test-suite.src ] && [ ! -h test-suite ]; then
         ln -s ../../test-suite.src test-suite
     fi
-    if [ ! -h compiler-rt ]; then
+    if [ -d $BuildDir/compiler-rt.src ] && [ ! -h compiler-rt ]; then
         ln -s ../../compiler-rt.src compiler-rt
     fi
-    if [ ! -h libcxx ]; then
+    if [ -d $BuildDir/libcxx.src ] && [ ! -h libcxx ]; then
         ln -s ../../libcxx.src libcxx
     fi
-    if [ ! -h libcxxabi ]; then
+    if [ -d $BuildDir/libcxxabi.src ] && [ ! -h libcxxabi ]; then
         ln -s ../../libcxxabi.src libcxxabi
     fi
-    if [ ! -h libunwind ]; then
+    if [ -d $BuildDir/libunwind.src ] && [ ! -h libunwind ]; then
         ln -s ../../libunwind.src libunwind
     fi