[clang] 04c3071 - [Driver] Flush file in locked area

[Serge Pavlov via cfe-commits]

Author: Serge Pavlov
Date: 2021-02-26T19:02:54+07:00
New Revision: 04c3071c16d799a4406c1742f239e8381c00b2b8

URL: https://github.com/llvm/llvm-project/commit/04c3071c16d799a4406c1742f239e8381c00b2b8
DIFF: https://github.com/llvm/llvm-project/commit/04c3071c16d799a4406c1742f239e8381c00b2b8.diff

LOG: [Driver] Flush file in locked area

When writing report file by option -proc-stat-report some part of output
can be written to unlocked file because destructor of raw_fd_ostream
calls `flush()`. In high thread contention environment it can result in
file operation failure. With this change `flush` is called explicitly when
file is locked, so call of `flush()` in the destructor does not cause
write to file.

Added: 
    

Modified: 
    clang/lib/Driver/Driver.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index 5aa0011d80ef..84bee2ae9d07 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -4069,6 +4069,7 @@ void Driver::BuildJobs(Compilation &C) const {
           return;
         }
         OS << Buffer;
+        OS.flush();
       }
     });
   }