diff --git a/src/fish_test_helper.cpp b/src/fish_test_helper.cpp
index b434d93a1..9ba502dc9 100644
--- a/src/fish_test_helper.cpp
+++ b/src/fish_test_helper.cpp
@@ -48,12 +48,13 @@ static void print_stdout_stderr() {
 }
 
 static void print_pid_then_sleep() {
-    fprintf(stdout, "%d\n", getpid());
+    // On some systems getpid is a long, on others it's an int, let's just cast it.
+    fprintf(stdout, "%ld\n", (long)getpid());
     fflush(nullptr);
     usleep(1000000 / 2);  //.5 secs
 }
 
-static void print_pgrp() { fprintf(stdout, "%d\n", getpgrp()); }
+static void print_pgrp() { fprintf(stdout, "%ld\n", (long)getpgrp()); }
 
 static void print_fds() {
     bool needs_space = false;