check_cflags -Wmissing-prototypes
check_cflags -Wstrict-prototypes
enabled extra_warnings && check_cflags -Winline
-enabled extra_warnings || check_cflags -Wno-maybe-uninitialized
# add some linker flags
check_ldflags -Wl,--warn-common
check_cflags -Werror=return-type
check_cflags -Werror=declaration-after-statement
check_cflags -Werror=vla
+ enabled extra_warnings || check_cflags -Wno-maybe-uninitialized
elif enabled llvm_gcc; then
check_cflags -mllvm -stack-alignment=16
elif enabled clang; then