diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5b3c9e8c..82407a46 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -161,10 +161,8 @@ if(${CMAKE_CXX_COMPILER_ID} MATCHES "GNU")
         add_compile_options(-Werror=deprecated-copy)
     endif()
 
-    if(NOT CMAKE_VERSION VERSION_LESS "3.13" AND NOT CMAKE_SYSTEM_NAME STREQUAL "Darwin")
+    if(NOT CMAKE_SYSTEM_NAME STREQUAL "OpenBSD" AND NOT CMAKE_SYSTEM_NAME STREQUAL "Darwin")
         # Error if there's symbols that are not found at link time.
-        # add_link_options() was added in CMake 3.13 - if using an earlier
-        # version don't set this - it should be caught by presubmits anyway.
         add_link_options("-Wl,--no-undefined")
     endif()
 elseif(${CMAKE_CXX_COMPILER_ID} MATCHES "Clang" AND NOT MSVC)
@@ -178,10 +176,8 @@ elseif(${CMAKE_CXX_COMPILER_ID} MATCHES "Clang" AND NOT MSVC)
         add_compile_options(-fno-exceptions)
     endif()
 
-    if(NOT CMAKE_VERSION VERSION_LESS "3.13")
+    if(NOT CMAKE_SYSTEM_NAME STREQUAL "OpenBSD")
         # Error if there's symbols that are not found at link time.
-        # add_link_options() was added in CMake 3.13 - if using an earlier
-        # version don't set this - it should be caught by presubmits anyway.
         if (CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang")
             add_link_options("-Wl,-undefined,error")
         else()