https://bugs.gentoo.org/856100
--- a/cmake/XercesWarnings.cmake
+++ b/cmake/XercesWarnings.cmake
@@ -50,8 +50,7 @@ if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" OR
       -Wswitch-default
       -Wunused-variable
       -Wwrite-strings
-      -Wno-variadic-macros
-      -fstrict-aliasing)
+      -Wno-variadic-macros)
   if(extra-warnings)
     list(APPEND test_flags
         -Wfloat-equal