diff --git a/src/libImaging/Access.c b/src/libImaging/Access.c
index 6c41fc091..95586d7ed 100644
--- a/src/libImaging/Access.c
+++ b/src/libImaging/Access.c
@@ -189,4 +189,4 @@ void
 _ImagingAccessDelete(Imaging im, ImagingAccess access) {}
 
 void
-ImagingAccessFree() {}
+ImagingAccessFree(void) {}
diff --git a/src/libImaging/Convert.c b/src/libImaging/Convert.c
index 2bc054616..48259dcdc 100644
--- a/src/libImaging/Convert.c
+++ b/src/libImaging/Convert.c
@@ -1650,7 +1650,7 @@ ImagingConvertInPlace(Imaging imIn, const Mode *mode) {
 /* ------------------ */
 
 void
-ImagingConvertInit() {
+ImagingConvertInit(void) {
     const struct Converter temp[] = {
         {IMAGING_MODE_1, IMAGING_MODE_L, bit2l},
         {IMAGING_MODE_1, IMAGING_MODE_I, bit2i},
@@ -1792,6 +1792,6 @@ ImagingConvertInit() {
 }
 
 void
-ImagingConvertFree() {
+ImagingConvertFree(void) {
     free(converters);
 }