Suspend background processes while writing to shared data structures

1 files changed, 1 insertions, 0 deletions

diff --git a/Build.PL b/Build.PL
index 5c650ce73..335ad0504 100644
--- a/Build.PL
+++ b/Build.PL
@@ -19,6 +19,7 @@ my %prereqs = qw(
     Scalar::Util                    0
     Test::Harness                   0
     Test::More                      0
+    Thread::Semaphore               0
     IO::Scalar                      0
     Time::HiRes                     0
 );