From ab694cd8453e10158fa61c0a0028a6bd3f474436 Mon Sep 17 00:00:00 2001
From: Zequan Wu <zequanwu@google.com>
Date: Fri, 1 Oct 2021 14:37:09 -0700
Subject: [PATCH] [Profile] Add a warning when lock file failed in
 __llvm_profile_set_file_object with continuous mode

---
 compiler-rt/lib/profile/InstrProfilingFile.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/compiler-rt/lib/profile/InstrProfilingFile.c b/compiler-rt/lib/profile/InstrProfilingFile.c
index 2070f93..e830d36 100644
--- a/compiler-rt/lib/profile/InstrProfilingFile.c
+++ b/compiler-rt/lib/profile/InstrProfilingFile.c
@@ -1153,7 +1153,10 @@ COMPILER_RT_VISIBILITY int __llvm_profile_set_file_object(FILE *File,
                 fileno(File));
       return 1;
     }
-    lprofLockFileHandle(File);
+    if (lprofLockFileHandle(File) != 0) {
+      PROF_WARN("Data may be corrupted during profile merging : %s\n",
+                "Fail to obtain file lock due to system limit.");
+    }
     uint64_t ProfileFileSize = 0;
     if (getProfileFileSizeForMerging(File, &ProfileFileSize) == -1) {
       lprofUnlockFileHandle(File);
-- 
2.7.4