diff --git a/3rdparty/portmidi/pm_mac/finddefault.c b/3rdparty/portmidi/pm_mac/finddefault.c
index 225a8e010ea..b4556e98d91 100644
--- a/3rdparty/portmidi/pm_mac/finddefault.c
+++ b/3rdparty/portmidi/pm_mac/finddefault.c
@@ -17,7 +17,7 @@
    plist files (user and system) open at once (due to a simple
    memory management scheme).
 */
-PmDeviceID find_default_device(char *path, int input, PmDeviceID id)
+PmDeviceID find_default_device(const char *path, int input, PmDeviceID id)
 /* path -- the name of the preference we are searching for
    input -- true iff this is an input device
    id -- current default device id
diff --git a/3rdparty/portmidi/pm_mac/pmmacosxcm.h b/3rdparty/portmidi/pm_mac/pmmacosxcm.h
index ea79902d40b..ab8b5edbcb7 100644
--- a/3rdparty/portmidi/pm_mac/pmmacosxcm.h
+++ b/3rdparty/portmidi/pm_mac/pmmacosxcm.h
@@ -3,4 +3,4 @@
 PmError pm_macosxcm_init(void);
 void pm_macosxcm_term(void);
 
-PmDeviceID find_default_device(char *path, int input, PmDeviceID id);
+PmDeviceID find_default_device(const char *path, int input, PmDeviceID id);
diff --git a/3rdparty/portmidi/pm_mac/readbinaryplist.c b/3rdparty/portmidi/pm_mac/readbinaryplist.c
index 63f2c49f743..9c0eb9b592d 100644
--- a/3rdparty/portmidi/pm_mac/readbinaryplist.c
+++ b/3rdparty/portmidi/pm_mac/readbinaryplist.c
@@ -1012,7 +1012,7 @@ char *value_get_asciistring(value_ptr v)
 }
 
 
-value_ptr value_dict_lookup_using_string(value_ptr v, char *key)
+value_ptr value_dict_lookup_using_string(value_ptr v, const char *key)
 {
     dict_ptr dict;
     if (v->tag != kTAG_DICTIONARY) return NULL; // not a dictionary
@@ -1028,7 +1028,7 @@ value_ptr value_dict_lookup_using_string(value_ptr v, char *key)
     return NULL; /* not found */
 }
 
-value_ptr value_dict_lookup_using_path(value_ptr v, char *path)
+value_ptr value_dict_lookup_using_path(value_ptr v, const char *path)
 {
     char key[MAX_KEY_SIZE];
     while (*path) { /* more to the path */
diff --git a/3rdparty/portmidi/pm_mac/readbinaryplist.h b/3rdparty/portmidi/pm_mac/readbinaryplist.h
index 6c0e31d02e6..8b096d08e2e 100644
--- a/3rdparty/portmidi/pm_mac/readbinaryplist.h
+++ b/3rdparty/portmidi/pm_mac/readbinaryplist.h
@@ -79,8 +79,8 @@ void bplist_free_data(void);
 /*************** functions for accessing values ****************/
 
 char *value_get_asciistring(value_ptr v);
-value_ptr value_dict_lookup_using_string(value_ptr v, char *key);
-value_ptr value_dict_lookup_using_path(value_ptr v, char *path);
+value_ptr value_dict_lookup_using_string(value_ptr v, const char *key);
+value_ptr value_dict_lookup_using_path(value_ptr v, const char *path);
 
 /*************** functions for debugging ***************/