diff --git a/Modules/_bz2module.c b/Modules/_bz2module.c
index a67aec5..abc4d5d 100644
--- a/Modules/_bz2module.c
+++ b/Modules/_bz2module.c
@@ -263,7 +263,7 @@
 static void
 BZ2_Free(void* ctx, void *ptr)
 {
-    return PyMem_RawFree(ptr);
+    PyMem_RawFree(ptr);
 }
 
 static int
diff --git a/Modules/_lzmamodule.c b/Modules/_lzmamodule.c
index 711604d..5d610bf 100644
--- a/Modules/_lzmamodule.c
+++ b/Modules/_lzmamodule.c
@@ -132,7 +132,7 @@
 static void
 PyLzma_Free(void *opaque, void *ptr)
 {
-    return PyMem_RawFree(ptr);
+    PyMem_RawFree(ptr);
 }
 
 #if BUFSIZ < 8192
diff --git a/Modules/zlibmodule.c b/Modules/zlibmodule.c
index 2e5f473..f21184a 100644
--- a/Modules/zlibmodule.c
+++ b/Modules/zlibmodule.c
@@ -149,7 +149,7 @@
 static void
 PyZlib_Free(voidpf ctx, void *ptr)
 {
-    return PyMem_RawFree(ptr);
+    PyMem_RawFree(ptr);
 }
 
 PyDoc_STRVAR(compress__doc__,