diff --git a/.github/workflows/bsd.yml b/.github/workflows/bsd.yml
index 80f0219..17f3b3d 100644
--- a/.github/workflows/bsd.yml
+++ b/.github/workflows/bsd.yml
@@ -48,6 +48,10 @@ jobs:
             curl -L https://cpanmin.us | sudo perl - --notest --installdeps --with-configure --with-develop .
             perl Makefile.PL
             make
+            gcc -Wall pending_signal.c && for n in `seq 15`; do ./a.out; echo $?; done
+            echo BARRIER1
+            gcc -DREBLOCK -Wall pending_signal.c && for n in `seq 15`; do ./a.out; echo $?; done
+            echo BARRIER2
             ktrace -di env IPCRUNDEBUG=gory perl -Iblib/lib t/kill_kill.t || true
             kdump || true
             IPCRUNDEBUG=gory prove -wlvmb t/kill_kill.t
diff --git a/pending_signal.c b/pending_signal.c
index dd74881..6b42ed6 100644
--- a/pending_signal.c
+++ b/pending_signal.c
@@ -4,8 +4,19 @@
  * 2 if sigprocmask(SIG_UNBLOCK) returns w/ SIGTERM *not* pending
  * 90 if exec fails
  *
- * Dies to SIGTERM about half the time, returning 1 the other half.  Compiling
- * with -DREBLOCK makes it die to SIGTERM always.
+ * Linux 3.10.0-1160.99.1.el7.x86_64: Dies to SIGTERM about half the time,
+ * returning 1 the other half.  Compiling with -DREBLOCK makes it die to SIGTERM
+ * always.
+ *
+ * AIX 7300-01-02-2320: returns 1 always.  Compiling with -DREBLOCK makes it die
+ * to SIGTERM always.
+ *
+ * Same as AIX:
+ * Darwin 21.6.0
+ * FreeBSD 14.0-CURRENT
+ * Linux 6.7.12-amd64
+ * OpenBSD 7.5
+ * Solaris 11.4.68.164.2
  */
 #include <signal.h>
 #include <unistd.h>