diff --git a/src/test/util_tests.cpp b/src/test/util_tests.cpp
--- a/src/test/util_tests.cpp
+++ b/src/test/util_tests.cpp
@@ -1279,7 +1279,14 @@
                 break;
             case ExitCommand:
                 close(fd);
-                exit(0);
+                // As an alternative to exit() which runs the exit handlers
+                // (which seem to be flakey with Boost test suite with JUNIT
+                // logging in a forked process), just vanish this process as
+                // fast as possible. This also stops valgrind from looking into
+                // this uninteresting subprocess. (quick_exit() would also work,
+                // but it triggers a spurious glibc-valgrind error in pre-3.15
+                // versions.)
+                execlp("true", (char *)NULL);
             default:
                 assert(0);
         }