diff --git a/boards/sim/sim/sim/configs/cxxtest/defconfig b/boards/sim/sim/sim/configs/cxxtest/defconfig
index 4dd7aced4c..92a2250aff 100644
--- a/boards/sim/sim/sim/configs/cxxtest/defconfig
+++ b/boards/sim/sim/sim/configs/cxxtest/defconfig
@@ -11,6 +11,8 @@ CONFIG_ARCH_BOARD_SIM=y
 CONFIG_ARCH_CHIP="sim"
 CONFIG_ARCH_SIM=y
 CONFIG_BOARD_LOOPSPERMSEC=100
+CONFIG_CXX_EXCEPTION=y
+CONFIG_CXX_RTTI=y
 CONFIG_HAVE_CXX=y
 CONFIG_IDLETHREAD_STACKSIZE=4096
 CONFIG_INIT_ENTRYPOINT="cxxtest_main"
diff --git a/boards/sim/sim/sim/configs/libcxxtest/defconfig b/boards/sim/sim/sim/configs/libcxxtest/defconfig
index fa8153325c..d867438364 100644
--- a/boards/sim/sim/sim/configs/libcxxtest/defconfig
+++ b/boards/sim/sim/sim/configs/libcxxtest/defconfig
@@ -17,6 +17,7 @@ CONFIG_BOARD_LOOPSPERMSEC=0
 CONFIG_BOOT_RUNFROMEXTSRAM=y
 CONFIG_BUILTIN=y
 CONFIG_CXX_EXCEPTION=y
+CONFIG_CXX_RTTI=y
 CONFIG_DEBUG_ASSERTIONS=y
 CONFIG_DEBUG_BINFMT=y
 CONFIG_DEBUG_BINFMT_ERROR=y