diff --git a/CMakeLists.txt b/CMakeLists.txt
index b956f4a68bb30890248ba878504a0bfee77ee802..3aa0baeffae5d55e429d9de51278ca77f0316b33 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -621,6 +621,10 @@ if (CLANG_ENABLE_BOOTSTRAP)
     COMMENT "Clobberring bootstrap build and stamp directories"
     )
 
+  if(CMAKE_VERBOSE_MAKEFILE)
+    set(verbose -DCMAKE_VERBOSE_MAKEFILE=On)
+  endif()
+
   ExternalProject_Add(bootstrap
     DEPENDS clang ${LTO_DEP}
     PREFIX bootstrap
@@ -636,7 +640,7 @@ if (CLANG_ENABLE_BOOTSTRAP)
                 -DCMAKE_CXX_COMPILER=${LLVM_RUNTIME_OUTPUT_INTDIR}/clang++
                 -DCMAKE_C_COMPILER=${LLVM_RUNTIME_OUTPUT_INTDIR}/clang
                 -DCMAKE_ASM_COMPILER=${LLVM_RUNTIME_OUTPUT_INTDIR}/clang
-                ${LTO_LIBRARY} ${LTO_AR} ${LTO_RANLIB}
+                ${LTO_LIBRARY} ${LTO_AR} ${LTO_RANLIB} ${verbose}
     INSTALL_COMMAND ""
     STEP_TARGETS configure build
     ${cmake_3_4_USES_TERMINAL_OPTIONS}