Remove use of deprecated ustat interface in glibc 2.28:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85835

Adapted to GCC 4 series from this upstream patch:
https://gcc.gnu.org/viewcvs/gcc?view=revision&revision=260684

--- a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc
+++ b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc
@@ -81,7 +81,6 @@
 #include <sys/statvfs.h>
 #include <sys/timex.h>
 #include <sys/user.h>
-#include <sys/ustat.h>
 #include <linux/cyclades.h>
 #include <linux/if_eql.h>
 #include <linux/if_plip.h>
@@ -163,7 +162,19 @@
   unsigned struct_old_utsname_sz = sizeof(struct old_utsname);
   unsigned struct_oldold_utsname_sz = sizeof(struct oldold_utsname);
   unsigned struct_itimerspec_sz = sizeof(struct itimerspec);
-  unsigned struct_ustat_sz = sizeof(struct ustat);
+  // Use pre-computed size of struct ustat to avoid <sys/ustat.h> which
+  // has been removed from glibc 2.28.
+#if de</td></tr></table>
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