-Wall dnl
-Wnull-dereference dnl
-Wundef dnl
+ -Wredundant-decls dnl
+ -Wmissing-noreturn dnl
+ -Wlogical-op dnl
dnl We currently get this warning when building with Clang:
dnl
dnl /usr/include/setjmp.h:54:12: error: declaration of built-in function '__sigsetjmp' requires the declaration of the 'jmp_buf' type, commonly provided in the header <setjmp.h>. [-Werror,-Wincomplete-setjmp-declaration]