Merging r333213:
    
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    r333213 | ctopper | 2018-05-24 10:59:47 -0700 (Thu, 24 May 2018) | 16 lines
    
    sanitizer: Use pre-computed size of struct ustat for Linux
    
    <sys/ustat.h> has been removed from glibc 2.28 by:
    
    commit cf2478d53ad7071e84c724a986b56fe17f4f4ca7
    Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
    Date: Sun Mar 18 11:28:59 2018 +0800
    
    Deprecate ustat syscall interface
    This patch uses pre-computed size of struct ustat for Linux to fix
    
    https://bugs.llvm.org/show_bug.cgi?id=37418
    
    Patch by H.J. Lu.
    
    Differential Revision: https://reviews.llvm.org/D47281
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    llvm-svn: 334776