diff --git a/test/integration/mallocx.c b/test/integration/mallocx.c
index 35d72093..fd960f30 100644
--- a/test/integration/mallocx.c
+++ b/test/integration/mallocx.c
@@ -154,7 +154,7 @@ TEST_BEGIN(test_alignment_and_size) {
 	const char *percpu_arena;
 	size_t sz = sizeof(percpu_arena);
 
-	if(mallctl("opt.percpu_arena", &percpu_arena, &sz, NULL, 0) ||
+	if(mallctl("opt.percpu_arena", (void *)&percpu_arena, &sz, NULL, 0) ||
 	    strcmp(percpu_arena, "disabled") != 0) {
 		test_skip("test_alignment_and_size skipped: "
 		    "not working with percpu arena.");
diff --git a/test/unit/mallctl.c b/test/unit/mallctl.c
index c9ba6c5d..f8b180b1 100644
--- a/test/unit/mallctl.c
+++ b/test/unit/mallctl.c
@@ -334,7 +334,7 @@ TEST_BEGIN(test_thread_arena) {
 
 	const char *opa;
 	size_t sz = sizeof(opa);
-	assert_d_eq(mallctl("opt.percpu_arena", &opa, &sz, NULL, 0), 0,
+	assert_d_eq(mallctl("opt.percpu_arena", (void *)&opa, &sz, NULL, 0), 0,
 	    "Unexpected mallctl() failure");
 
 	sz = sizeof(unsigned);