diff --git a/external/backtrace-cpp/CMakeLists.txt b/external/backtrace-cpp/CMakeLists.txt
index 9105758011ffccc21a636aa2f5a792a1a4448b53..b31bb8c36c4f9f4b36b7e03151f59c35c6211a60 100644
--- a/external/backtrace-cpp/CMakeLists.txt
+++ b/external/backtrace-cpp/CMakeLists.txt
@@ -38,7 +38,7 @@ if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang" OR CMAKE_COMPILER_IS_GNUCXX)
 endif()
 
 # ANBOX: allow old-style casts
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-error=old-style-cast -Wno-error=switch-default -Wno-error=implicit-fallthrough")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-error=old-style-cast -Wno-error=switch-default")
 
 ###############################################################################
 # BACKWARD OBJECT
diff --git a/external/backtrace-cpp/backward.hpp b/external/backtrace-cpp/backward.hpp
index 37be193eaba64f2dec0239bad273035794689d79..fd040679edc5e89d3f8dfaeb258d676cfb6bd951 100644
--- a/external/backtrace-cpp/backward.hpp
+++ b/external/backtrace-cpp/backward.hpp
@@ -1391,6 +1391,7 @@ private:
 					if (die_has_pc(die, pc)) {
 						return result;
 					}
+					/* fall through */
 				default:
 					bool declaration = false;
 					Dwarf_Attribute attr_mem;