diff --git a/lldb/tools/debugserver/source/MacOSX/CMakeLists.txt b/lldb/tools/debugserver/source/MacOSX/CMakeLists.txt
index 6d8e1ee449e3..59812b27dff2 100644
--- a/lldb/tools/debugserver/source/MacOSX/CMakeLists.txt
+++ b/lldb/tools/debugserver/source/MacOSX/CMakeLists.txt
@@ -10,7 +10,7 @@
 # CFLAGS etc explicitly. Switching on LLVM_HOST_TRIPLE is also an option,
 # but it breaks down when cross-compiling.
 
-string(REGEX MATCH "^[^-]*" LLDB_DEBUGSERVER_ARCH ${LLVM_DEFAULT_TARGET_TRIPLE})
+string(REGEX MATCH "^[^-]*" LLDB_DEBUGSERVER_ARCH "${LLVM_DEFAULT_TARGET_TRIPLE}")
 
 if("${LLDB_DEBUGSERVER_ARCH}" MATCHES ".*arm.*")
   list(APPEND SOURCES arm/DNBArchImpl.cpp arm64/DNBArchImplARM64.cpp)