[libcxx-commits] [PATCH] D124555: [libcxx] basic_ios<wchar_t> cannot store fill character WCHAR_MAX

[Hubert Tong via Phabricator via libcxx-commits]

hubert.reinterpretcast added inline comments.


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Comment at: libcxx/include/__config:319
 
+#if defined(_AIX)
+#  define _LIBCPP_BASIC_IOS_HAS_FILL_SET 1
----------------
It is my understanding that z/OS is also in the same situation.


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Comment at: libcxx/include/__config:322
+#elif _WIN32 ||                                                                                                        \
+     (defined(__linux__) && (defined(_M_ARM) || defined(__arm__) || defined(_M_ARM64) || defined(__aarch64__)))
+#  define _LIBCPP_BASIC_IOS_HAS_FILL_SET 0
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It seems to me that `_M_ARM` and `_M_ARM64` is associated with Windows and not Linux.


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Comment at: libcxx/include/ios:709
+        static const bool value = 
+            (WEOF >= (wint_t)WCHAR_MIN || WEOF <= (wint_t)WCHAR_MAX);
+    };
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If `wchar_t` is 16-bit unsigned, `wint_t` is 32-bit signed and `WEOF` is `-1`, then `WEOF` is less than `(wint_t)WCHAR_MAX` and `value` becomes `true` even though the new member is unneeded.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D124555/new/

https://reviews.llvm.org/D124555