[libcxx-commits] [libcxx] e21ab31 - [libc++] Eliminate <compare>'s dependency on <array>.

[Arthur O'Dwyer via libcxx-commits]

Author: Arthur O'Dwyer
Date: 2021-03-25T10:34:35-04:00
New Revision: e21ab31f45a440e195f9c914083d57718e0de3b7

URL: https://github.com/llvm/llvm-project/commit/e21ab31f45a440e195f9c914083d57718e0de3b7
DIFF: https://github.com/llvm/llvm-project/commit/e21ab31f45a440e195f9c914083d57718e0de3b7.diff

LOG: [libc++] Eliminate <compare>'s dependency on <array>.

This refactor is not only a good idea, but is in fact required by the standard,
in the sense that <array> is mandated to include <compare>.
So <compare> shouldn't have a circular dependency on <array>!

Differential Revision: https://reviews.llvm.org/D99307

Added: 
    

Modified: 
    libcxx/include/compare

Removed: 
    


################################################################################
diff  --git a/libcxx/include/compare b/libcxx/include/compare
index 048f4821dd4e..12c7aa0a740e 100644
--- a/libcxx/include/compare
+++ b/libcxx/include/compare
@@ -126,7 +126,6 @@ namespace std {
 
 #include <__config>
 #include <type_traits>
-#include <array>
 
 #ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
 #pragma GCC system_header
@@ -701,8 +700,8 @@ constexpr _ClassifyCompCategory __type_to_enum() noexcept {
 
 template <size_t _Size>
 constexpr _ClassifyCompCategory
-__compute_comp_type(array<_ClassifyCompCategory, _Size> __types) {
-  array<int, _CCC_Size> __seen = {};
+__compute_comp_type(const _ClassifyCompCategory (&__types)[_Size]) {
+  int __seen[_CCC_Size] = {};
   for (auto __type : __types)
     ++__seen[__type];
   if (__seen[_None])
@@ -723,9 +722,8 @@ __compute_comp_type(array<_ClassifyCompCategory, _Size> __types) {
 template <class ..._Ts>
 constexpr auto __get_comp_type() {
   using _CCC = _ClassifyCompCategory;
-  constexpr array<_CCC, sizeof...(_Ts)> __type_kinds{{__comp_detail::__type_to_enum<_Ts>()...}};
-  constexpr _CCC _Cat = sizeof...(_Ts) == 0 ? _StrongOrd
-      : __compute_comp_type(__type_kinds);
+  constexpr _CCC __type_kinds[] = {_StrongOrd, __type_to_enum<_Ts>()...};
+  constexpr _CCC _Cat = __compute_comp_type(__type_kinds);
   if constexpr (_Cat == _None)
     return void();
   else if constexpr (_Cat == _WeakEq)