diff --git a/common/getopt.c b/common/getopt.c
index 74ef97d9..21ec6fb1 100644
--- a/common/getopt.c
+++ b/common/getopt.c
@@ -86,6 +86,11 @@ void getopt_option_destroy(getopt_option_t *goo)
     free(goo);
 }
 
+void getopt_option_destroy_void(void *goo)
+{
+    getopt_option_destroy((getopt_option_t *)goo);
+}
+
 void getopt_destroy(getopt_t *gopt)
 {
     // free the extra arguments and container
@@ -94,7 +99,7 @@ void getopt_destroy(getopt_t *gopt)
 
     // deep free of the getopt_option structs. Also frees key/values, so
     // after this loop, hash tables will no longer work
-    zarray_vmap(gopt->options, getopt_option_destroy);
+    zarray_vmap(gopt->options, getopt_option_destroy_void);
     zarray_destroy(gopt->options);
 
     // free tables
diff --git a/common/getopt.h b/common/getopt.h
index 69dbb05c..1f036628 100644
--- a/common/getopt.h
+++ b/common/getopt.h
@@ -38,6 +38,7 @@ typedef struct getopt getopt_t;
 
 getopt_t *getopt_create();
 void getopt_destroy(getopt_t *gopt);
+void getopt_option_destroy_void(void *goo);
 
 // Parse args. Returns 1 on success
 int getopt_parse(getopt_t *gopt, int argc, char *argv[], int showErrors);
diff --git a/common/zarray.c b/common/zarray.c
index 43e6a7e0..fa1f8a25 100644
--- a/common/zarray.c
+++ b/common/zarray.c
@@ -41,7 +41,7 @@ int zstrcmp(const void * a_pp, const void * b_pp)
     return strcmp(a,b);
 }
 
-void zarray_vmap(zarray_t *za, void (*f)())
+void zarray_vmap(zarray_t *za, void (*f)(void*))
 {
     assert(za != NULL);
     assert(f != NULL);
diff --git a/common/zarray.h b/common/zarray.h
index 22b4c2bb..1c9da4a6 100644
--- a/common/zarray.h
+++ b/common/zarray.h
@@ -355,7 +355,7 @@ static inline void zarray_map(zarray_t *za, void (*f)(void*))
  *
  * void map_function(element_type *element)
  */
-    void zarray_vmap(zarray_t *za, void (*f)());
+    void zarray_vmap(zarray_t *za, void (*f)(void *));
 
 /**
  * Removes all elements from the array and sets its size to zero. Pointers to
diff --git a/common/zhash.c b/common/zhash.c
index faf52233..b4a2ec09 100644
--- a/common/zhash.c
+++ b/common/zhash.c
@@ -352,7 +352,7 @@ void zhash_iterator_remove(zhash_iterator_t *zit)
     zit->last_entry--;
 }
 
-void zhash_map_keys(zhash_t *zh, void (*f)())
+void zhash_map_keys(zhash_t *zh, void (*f)(void*))
 {
     assert(zh != NULL);
     if (f == NULL)
@@ -368,7 +368,7 @@ void zhash_map_keys(zhash_t *zh, void (*f)())
     }
 }
 
-void zhash_vmap_keys(zhash_t * zh, void (*f)())
+void zhash_vmap_keys(zhash_t * zh, void (*f)(void*))
 {
     assert(zh != NULL);
     if (f == NULL)
@@ -385,7 +385,7 @@ void zhash_vmap_keys(zhash_t * zh, void (*f)())
     }
 }
 
-void zhash_map_values(zhash_t * zh, void (*f)())
+void zhash_map_values(zhash_t * zh, void (*f)(void*))
 {
     assert(zh != NULL);
     if (f == NULL)
@@ -400,7 +400,7 @@ void zhash_map_values(zhash_t * zh, void (*f)())
     }
 }
 
-void zhash_vmap_values(zhash_t * zh, void (*f)())
+void zhash_vmap_values(zhash_t * zh, void (*f)(void*))
 {
     assert(zh != NULL);
     if (f == NULL)
diff --git a/common/zhash.h b/common/zhash.h
index f3dee1aa..9993a66e 100644
--- a/common/zhash.h
+++ b/common/zhash.h
@@ -259,7 +259,7 @@ void zhash_iterator_remove(zhash_iterator_t *zit);
  * for the key, which the caller should not modify, as the hash table will not be
  * re-indexed. The function may be NULL, in which case no action is taken.
  */
-void zhash_map_keys(zhash_t *zh, void (*f)());
+void zhash_map_keys(zhash_t *zh, void (*f)(void *));
 
 /**
  * Calls the supplied function with a pointer to every value in the hash table in
@@ -267,7 +267,7 @@ void zhash_map_keys(zhash_t *zh, void (*f)());
  * for the value, which the caller may safely modify. The function may be NULL,
  * in which case no action is taken.
  */
-void zhash_map_values(zhash_t *zh, void (*f)());
+void zhash_map_values(zhash_t *zh, void (*f)(void *));
 
 /**
  * Calls the supplied function with a copy of every key in the hash table in
@@ -280,7 +280,7 @@ void zhash_map_values(zhash_t *zh, void (*f)());
  * Use with non-pointer keys (i.e. integer, double, etc.) will likely cause a
  * segmentation fault.
  */
-void zhash_vmap_keys(zhash_t *vh, void (*f)());
+void zhash_vmap_keys(zhash_t *vh, void (*f)(void *));
 
 /**
  * Calls the supplied function with a copy of every value in the hash table in
@@ -293,7 +293,7 @@ void zhash_vmap_keys(zhash_t *vh, void (*f)());
  * Use with non-pointer values (i.e. integer, double, etc.) will likely cause a
  * segmentation fault.
  */
-void zhash_vmap_values(zhash_t *vh, void (*f)());
+void zhash_vmap_values(zhash_t *vh, void (*f)(void *));
 
 /**
  * Returns an array which contains copies of all of the hash table's keys, in no
diff --git a/common/zmaxheap.c b/common/zmaxheap.c
index 7479f053..3ca30af7 100644
--- a/common/zmaxheap.c
+++ b/common/zmaxheap.c
@@ -167,7 +167,7 @@ void zmaxheap_add(zmaxheap_t *heap, void *p, float v)
     }
 }
 
-void zmaxheap_vmap(zmaxheap_t *heap, void (*f)())
+void zmaxheap_vmap(zmaxheap_t *heap, void (*f)(void*))
 {
     assert(heap != NULL);
     assert(f != NULL);
diff --git a/common/zmaxheap.h b/common/zmaxheap.h
index f0020f92..2f4a90d6 100644
--- a/common/zmaxheap.h
+++ b/common/zmaxheap.h
@@ -39,7 +39,7 @@ struct zmaxheap_iterator {
 
 zmaxheap_t *zmaxheap_create(size_t el_sz);
 
-void zmaxheap_vmap(zmaxheap_t *heap, void (*f)());
+void zmaxheap_vmap(zmaxheap_t *heap, void (*f)(void *));
 
 void zmaxheap_destroy(zmaxheap_t *heap);