[compiler-rt][builtins] Enable more warnings in add_security_warnings

[ahatanak]

Summary

Enable -Wsizeof-array-div and -Wsizeof-pointer-divcompiler.

Also, replace -Wmemset-transposed-args with -Wsuspicious-memaccess. The latter automatically enables the former and a few other warnings.

compiler-rt/cmake/Modules/CompilerRTUtils.cmake

function(add_security_warnings out_flags macosx_sdk_version)
   set(flags "${${out_flags}}")
 
   append_list_if(COMPILER_RT_HAS_ARRAY_BOUNDS_FLAG -Werror=array-bounds flags)
   append_list_if(COMPILER_RT_HAS_UNINITIALIZED_FLAG -Werror=uninitialized flags)
   append_list_if(COMPILER_RT_HAS_SHADOW_FLAG -Werror=shadow flags)
   append_list_if(COMPILER_RT_HAS_EMPTY_BODY_FLAG -Werror=empty-body flags)
   append_list_if(COMPILER_RT_HAS_SIZEOF_POINTER_MEMACCESS_FLAG -Werror=sizeof-pointer-memaccess flags)
   append_list_if(COMPILER_RT_HAS_SIZEOF_ARRAY_ARGUMENT_FLAG -Werror=sizeof-array-argument flags)
-  append_list_if(COMPILER_RT_HAS_MEMSET_TRANSPOSED_ARGS_FLAG -Werror=memset-transposed-args flags)
+  append_list_if(COMPILER_RT_HAS_SUSPICIOUS_MEMACCESS_FLAG -Werror=suspicious-memaccess flags)
   append_list_if(COMPILER_RT_HAS_BUILTIN_MEMCPY_CHK_SIZE_FLAG -Werror=builtin-memcpy-chk-size flags)
   append_list_if(COMPILER_RT_HAS_ARRAY_BOUNDS_POINTER_ARITHMETIC_FLAG -Werror=array-bounds-pointer-arithmetic flags)
   append_list_if(COMPILER_RT_HAS_RETURN_STACK_ADDRESS_FLAG -Werror=return-stack-address flags)
   append_list_if(COMPILER_RT_HAS_SIZEOF_ARRAY_DECAY_FLAG -Werror=sizeof-array-decay flags)
   append_list_if(COMPILER_RT_HAS_FORMAT_INSUFFICIENT_ARGS_FLAG -Werror=format-insufficient-args flags)
   append_list_if(COMPILER_RT_HAS_BUILTIN_FORMAL_SECURITY_FLAG -Werror=format-security flags)
+  append_list_if(COMPILER_RT_HAS_SIZEOF_ARRAY_DIV_FLAG -Werror=sizeof-array-div)
+  append_list_if(COMPILER_RT_HAS_SIZEOF_POINTER_DIV_FLAG -Werror=sizeof-pointer-div)
 
   # Add -Wformat-nonliteral only if we can avoid adding the definition of
   # eprintf. On Apple platforms, eprintf is needed only on macosx and only if
   # its version is older than 10.7.
   if ("${macosx_sdk_version}" VERSION_GREATER_EQUAL 10.7)
     list(APPEND flags -Werror=format-nonliteral -DDONT_DEFINE_EPRINTF)
   endif()
 
   set(${out_flags} "${flags}" PARENT_SCOPE)
 endfunction()

compiler-rt/cmake/config-ix.cmake

 check_cxx_compiler_flag(/wd4800 COMPILER_RT_HAS_WD4800_FLAG)
 
 check_cxx_compiler_flag(-Werror -Warray-bounds COMPILER_RT_HAS_ARRAY_BOUNDS_FLAG)
 check_cxx_compiler_flag(-Werror -Wuninitialized COMPILER_RT_HAS_UNINITIALIZED_FLAG)
 check_cxx_compiler_flag(-Werror -Wshadow COMPILER_RT_HAS_SHADOW_FLAG)
 check_cxx_compiler_flag(-Werror -Wempty-body COMPILER_RT_HAS_EMPTY_BODY_FLAG)
 check_cxx_compiler_flag(-Werror -Wsizeof-pointer-memaccess COMPILER_RT_HAS_SIZEOF_POINTER_MEMACCESS_FLAG)
 check_cxx_compiler_flag(-Werror -Wsizeof-array-argument COMPILER_RT_HAS_SIZEOF_ARRAY_ARGUMENT_FLAG)
-check_cxx_compiler_flag(-Werror -Wmemset-transposed-args COMPILER_RT_HAS_MEMSET_TRANSPOSED_ARGS_FLAG)
+check_cxx_compiler_flag(-Werror -Wsuspicious-memaccess COMPILER_RT_HAS_SUSPICIOUS_MEMACCESS_FLAG)
 check_cxx_compiler_flag(-Werror -Wbuiltin-memcpy-chk-size COMPILER_RT_HAS_BUILTIN_MEMCPY_CHK_SIZE_FLAG)
 check_cxx_compiler_flag(-Werror -Warray-bounds-pointer-arithmetic COMPILER_RT_HAS_ARRAY_BOUNDS_POINTER_ARITHMETIC_FLAG)
 check_cxx_compiler_flag(-Werror -Wreturn-stack-address COMPILER_RT_HAS_RETURN_STACK_ADDRESS_FLAG)
 check_cxx_compiler_flag(-Werror -Wsizeof-array-decay COMPILER_RT_HAS_SIZEOF_ARRAY_DECAY_FLAG)
 check_cxx_compiler_flag(-Werror -Wformat-insufficient-args COMPILER_RT_HAS_FORMAT_INSUFFICIENT_ARGS_FLAG)
 check_cxx_compiler_flag(-Werror -Wformat-security COMPILER_RT_HAS_BUILTIN_FORMAL_SECURITY_FLAG)
+check_cxx_compiler_flag(-Werror -Wsizeof-array-div COMPILER_RT_HAS_SIZEOF_ARRAY_DIV_FLAG)
+check_cxx_compiler_flag(-Werror -Wsizeof-pointer-div COMPILER_RT_HAS_SIZEOF_POINTER_DIV_FLAG)
 
 # Symbols.
 check_symbol_exists(__func__ "" COMPILER_RT_HAS_FUNC_SYMBOL)
 
 # Includes.
 check_cxx_compiler_flag(-nostdinc++ COMPILER_RT_HAS_NOSTDINCXX_FLAG)
 check_cxx_compiler_flag(-nostdlib++ COMPILER_RT_HAS_NOSTDLIBXX_FLAG)
 check_include_files("sys/auxv.h"    COMPILER_RT_HAS_AUXV)