diff --git a/CMakeLists.txt b/CMakeLists.txt
index 51340f911..44bfe49df 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -366,7 +366,7 @@ endif()
 find_package(dune-common REQUIRED)
 opm_need_version_of ("dune-common")
 target_include_directories(dunecommon INTERFACE ${dune-common_INCLUDE_DIRS})
-string(REPLACE " " ";" dflags ${dune-common_CXX_FLAGS})
+string(REPLACE " " ";" dflags "${dune-common_CXX_FLAGS}")
 target_compile_options(dunecommon INTERFACE ${dflags})
 target_compile_definitions(dunecommon INTERFACE DUNE_COMMON_VERSION_MAJOR=${DUNE_COMMON_VERSION_MAJOR})
 target_compile_definitions(dunecommon INTERFACE DUNE_COMMON_VERSION_MINOR=${DUNE_COMMON_VERSION_MINOR})