Merging r341442:
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r341442 | bcain | 2018-09-05 04:15:54 +0200 (Wed, 05 Sep 2018) | 8 lines

Add glibc_prereq to platform limits mmsghdr

sendmmsg requires glibc >= 2.14.

Fixes PR38589.

Review: https://reviews.llvm.org/D51538

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git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/branches/release_70@341524 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/sanitizer_common/sanitizer_platform_limits_posix.cc b/lib/sanitizer_common/sanitizer_platform_limits_posix.cc
index c27055f..54da635 100644
--- a/lib/sanitizer_common/sanitizer_platform_limits_posix.cc
+++ b/lib/sanitizer_common/sanitizer_platform_limits_posix.cc
@@ -1037,7 +1037,11 @@
 CHECK_SIZE_AND_OFFSET(cmsghdr, cmsg_level);
 CHECK_SIZE_AND_OFFSET(cmsghdr, cmsg_type);
 
-#if SANITIZER_LINUX && (!defined(__ANDROID__) || __ANDROID_API__ >= 21)
+#ifndef __GLIBC_PREREQ
+#define __GLIBC_PREREQ(x, y) 0
+#endif
+
+#if SANITIZER_LINUX && (__ANDROID_API__ >= 21 || __GLIBC_PREREQ (2, 14))
 CHECK_TYPE_SIZE(mmsghdr);
 CHECK_SIZE_AND_OFFSET(mmsghdr, msg_hdr);
 CHECK_SIZE_AND_OFFSET(mmsghdr, msg_len);
@@ -1078,9 +1082,6 @@
 // Can't write checks for sa_handler and sa_sigaction due to them being
 // preprocessor macros.
 CHECK_STRUCT_SIZE_AND_OFFSET(sigaction, sa_mask);
-#ifndef __GLIBC_PREREQ
-#define __GLIBC_PREREQ(x, y) 0
-#endif
 #if !defined(__s390x__) || __GLIBC_PREREQ (2, 20)
 // On s390x glibc 2.19 and earlier sa_flags was unsigned long, and sa_resv
 // didn't exist.