diff --git a/DevTools/UserspaceEmulator/MmapRegion.cpp b/DevTools/UserspaceEmulator/MmapRegion.cpp
index 278776ab3c..3abe4092e7 100644
--- a/DevTools/UserspaceEmulator/MmapRegion.cpp
+++ b/DevTools/UserspaceEmulator/MmapRegion.cpp
@@ -26,6 +26,7 @@
 
 #include "MmapRegion.h"
 #include "Emulator.h"
+#include <string.h>
 #include <sys/mman.h>
 
 namespace UserspaceEmulator {
@@ -51,7 +52,8 @@ MmapRegion::MmapRegion(u32 base, u32 size, int prot)
     : Region(base, size)
     , m_prot(prot)
 {
-    m_shadow_data = (u8*)calloc(1, size);
+    m_shadow_data = (u8*)malloc(size);
+    memset(m_shadow_data, 1, size);
 }
 
 MmapRegion::~MmapRegion()
diff --git a/DevTools/UserspaceEmulator/SharedBufferRegion.cpp b/DevTools/UserspaceEmulator/SharedBufferRegion.cpp
index d6e2e4b1ea..02c4cfbb8f 100644
--- a/DevTools/UserspaceEmulator/SharedBufferRegion.cpp
+++ b/DevTools/UserspaceEmulator/SharedBufferRegion.cpp
@@ -28,6 +28,7 @@
 #include "Emulator.h"
 #include <Kernel/API/Syscall.h>
 #include <serenity.h>
+#include <string.h>
 #include <sys/mman.h>
 
 namespace UserspaceEmulator {
@@ -42,7 +43,8 @@ SharedBufferRegion::SharedBufferRegion(u32 base, u32 size, int shbuf_id, u8* hos
     , m_data(host_data)
     , m_shbuf_id(shbuf_id)
 {
-    m_shadow_data = (u8*)calloc(1, size);
+    m_shadow_data = (u8*)malloc(size);
+    memset(m_shadow_data, 1, size);
 }
 
 SharedBufferRegion::~SharedBufferRegion()