SERVER-41162 Show logs for death tests.

Death tests run in a child process.  That process communicates its
stdout and stderr to its parent via a pipe.  The results are
searched for a death-test string.  We now output the child's
output to the parent's stream, after collecting it for a later
search.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/mongo/unittest/death_test.cpp b/src/mongo/unittest/death_test.cpp
index 08d3fae9f17..04d8ed135bd 100644
--- a/src/mongo/unittest/death_test.cpp
+++ b/src/mongo/unittest/death_test.cpp
@@ -81,10 +81,14 @@ void DeathTestImpl::_doTest() {
         char buf[1000];
         std::ostringstream os;
         ssize_t bytesRead;
+        log() << "========== Beginning Interleaved output of Death Test ==========";
         while (0 < (bytesRead = read(pipes[0], buf, sizeof(buf)))) {
+            std::cerr.write(buf, bytesRead);
+            invariant(std::cerr);
             os.write(buf, bytesRead);
             invariant(os);
         }
+        log() << "========== Beginning Interleaved output of Death Test ==========";
         checkSyscall(bytesRead);
         pid_t pid;
         int stat;