diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0a277582..e873e8e9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -172,6 +172,7 @@ if(NOT MINIMAL_BUILD)
     COMMAND ${CMAKE_COMMAND} -E make_directory ${CIVETWEB_SRC}/install/include
     BUILD_IN_SOURCE 1
     BUILD_COMMAND ${CMD_MAKE} COPT="-DNO_FILES" WITH_CPP=1
+    BUILD_BYPRODUCTS ${CIVETWEB_LIB}
     INSTALL_COMMAND ${CMD_MAKE} COPT="-DNO_FILES" install-lib install-headers PREFIX=${CIVETWEB_SRC}/install "WITH_CPP=1")
 endif()