[llvm] r318462 - Fix some undefined beahvior in FileMapping.

[Zachary Turner via llvm-commits]

Author: zturner
Date: Thu Nov 16 14:39:55 2017
New Revision: 318462

URL: http://llvm.org/viewvc/llvm-project?rev=318462&view=rev
Log:
Fix some undefined beahvior in FileMapping.

This was broken when building a 32-bit native toolchain, as
shifting a size_t right by 32 is UB when sizeof(size_t) == 8.

Modified:
    llvm/trunk/lib/Support/Windows/Path.inc

Modified: llvm/trunk/lib/Support/Windows/Path.inc
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Windows/Path.inc?rev=318462&r1=318461&r2=318462&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Windows/Path.inc (original)
+++ llvm/trunk/lib/Support/Windows/Path.inc Thu Nov 16 14:39:55 2017
@@ -734,8 +734,8 @@ std::error_code mapped_file_region::init
 
   HANDLE FileMappingHandle =
       ::CreateFileMappingW(FileHandle, 0, flprotect,
-                           Size >> 32,
-                           Size & 0xffffffff,
+                           Hi_32(Size),
+                           Lo_32(Size),
                            0);
   if (FileMappingHandle == NULL) {
     std::error_code ec = mapWindowsError(GetLastError());