diff --git a/CMakeLists.txt b/CMakeLists.txt
index df03dd6073..8b26e6e7c7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -189,8 +189,7 @@ if(ENABLE_TESTING)
     endif(UNIX)
 endif()
 
-# Make scripts and data files needed for testing available in an
-# out-of-source build.
+# Make scripts needed for testing available in an out-of-source build.
 if (NOT ${CMAKE_CURRENT_BINARY_DIR} STREQUAL ${CMAKE_CURRENT_SOURCE_DIR})
     link_to_source(scripts)
 endif()
diff --git a/include/CMakeLists.txt b/include/CMakeLists.txt
index 3081b2678b..1b581a54dd 100644
--- a/include/CMakeLists.txt
+++ b/include/CMakeLists.txt
@@ -10,8 +10,7 @@ if(INSTALL_MBEDTLS_HEADERS)
 
 endif(INSTALL_MBEDTLS_HEADERS)
 
-# Make scripts and data files needed for testing available in an
-# out-of-source build.
+# Make config.h available in an out-of-source build. ssl-opt.sh requires it.
 if (NOT ${CMAKE_CURRENT_BINARY_DIR} STREQUAL ${CMAKE_CURRENT_SOURCE_DIR})
     link_to_source(mbedtls)
 endif()