[libcxx-commits] [libcxx] [libc++][AIX] Support file offsets larger than 2GB in basic_filebuf on 32-bit (PR #215892)

[Hubert Tong via libcxx-commits]

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@@ -779,6 +780,15 @@ const wchar_t* basic_filebuf<_CharT, _Traits>::__make_mdwstring(ios_base::openmo
 }
 #    endif
 
+template <class _CharT, class _Traits>
+FILE* basic_filebuf<_CharT, _Traits>::__fopen(const char* __name, const char* __mode) {
+#    if defined(_AIX) && !defined(__64BIT__)
+  return fopen64(__name, __mode);
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hubert-reinterpretcast wrote:

Where is `fopen64` declared? The AIX include files do not declare it by default. Also, if you are going to declare it, this is not a POSIX-reserved name (meaning users can `#define` it).

https://github.com/llvm/llvm-project/pull/215892