<div dir="ltr">Any chance of a test case?</div><br><div class="gmail_quote"><div dir="ltr">On Mon, Aug 6, 2018 at 9:22 AM Owen Reynolds via llvm-commits <<a href="mailto:llvm-commits@lists.llvm.org">llvm-commits@lists.llvm.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Author: gbreynoo<br>
Date: Mon Aug  6 09:21:41 2018<br>
New Revision: 339027<br>
<br>
URL: <a href="http://llvm.org/viewvc/llvm-project?rev=339027&view=rev" rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project?rev=339027&view=rev</a><br>
Log:<br>
Fix raw_fd_ostream::write_impl hang due to an infinite loop with large output<br>
<br>
On windows when raw_fd_ostream::write_impl calls write, a 32 bit input is required for character count. As a variable with size_t is used for this argument, on x64 integral demotion occurs. In the case of large files an infinite loop follows. <br>
See: <a href="https://bugs.llvm.org/show_bug.cgi?id=37926" rel="noreferrer" target="_blank">https://bugs.llvm.org/show_bug.cgi?id=37926</a><br>
This fix allows the output of files larger than the previous int32 limit.<br>
<br>
Differential Revision: <a href="https://reviews.llvm.org/D48948" rel="noreferrer" target="_blank">https://reviews.llvm.org/D48948</a><br>
<br>
Modified:<br>
    llvm/trunk/lib/Support/raw_ostream.cpp<br>
<br>
Modified: llvm/trunk/lib/Support/raw_ostream.cpp<br>
URL: <a href="http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/raw_ostream.cpp?rev=339027&r1=339026&r2=339027&view=diff" rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/raw_ostream.cpp?rev=339027&r1=339026&r2=339027&view=diff</a><br>
==============================================================================<br>
--- llvm/trunk/lib/Support/raw_ostream.cpp (original)<br>
+++ llvm/trunk/lib/Support/raw_ostream.cpp Mon Aug  6 09:21:41 2018<br>
@@ -613,10 +613,10 @@ void raw_fd_ostream::write_impl(const ch<br>
   assert(FD >= 0 && "File already closed.");<br>
   pos += Size;<br>
<br>
-  // The maximum write size is limited to SSIZE_MAX because a write<br>
-  // greater than SSIZE_MAX is implementation-defined in POSIX.<br>
-  // Since SSIZE_MAX is not portable, we use SIZE_MAX >> 1 instead.<br>
-  size_t MaxWriteSize = SIZE_MAX >> 1;<br>
+  // The maximum write size is limited to INT32_MAX. A write<br>
+  // greater than SSIZE_MAX is implementation-defined in POSIX,<br>
+  // and Windows _write requires 32 bit input.<br>
+  size_t MaxWriteSize = INT32_MAX;<br>
<br>
 #if defined(__linux__)<br>
   // It is observed that Linux returns EINVAL for a very large write (>2G).<br>
<br>
<br>
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</blockquote></div>