3 files changed, 4 insertions, 5 deletions
diff --git a/ext/socket/getaddrinfo.c b/ext/socket/getaddrinfo.c
index 5a3c1377f4..49fdf9b597 100644
--- a/ext/socket/getaddrinfo.c
+++ b/ext/socket/getaddrinfo.c
@@ -207,7 +207,6 @@ gai_strerror(int ecode)
 
 void
 freeaddrinfo(struct addrinfo *ai)
-	struct addrinfo *ai;
 {
 	struct addrinfo *next;
 
@@ -530,7 +529,7 @@ getaddrinfo(const char *hostname, const char *servname, const struct addrinfo *h
 }
 
 static int
-get_name(const char *addr, const struct aft *afd, struct addrinfo **res, char *numaddr, struct addrinfo *pai, int port0)
+get_name(const char *addr, const struct afd *afd, struct addrinfo **res, char *numaddr, struct addrinfo *pai, int port0)
 {
 	u_short port = port0 & 0xffff;
 	struct hostent *hp;
diff --git a/ext/tk/tcltklib.c b/ext/tk/tcltklib.c
index 862e817a7e..e9b553f35c 100644
--- a/ext/tk/tcltklib.c
+++ b/ext/tk/tcltklib.c
@@ -124,7 +124,7 @@ static VALUE tk_funcall _((VALUE(), int, VALUE*, VALUE));
 
 /* safe Tcl_Eval and Tcl_GlobalEval */
 static int
-tcl_eval(Tcp_Interp interp, const char *cmd)
+tcl_eval(Tcl_Interp *interp, const char *cmd)
 {
     char *buf = strdup(cmd);
     const int ret = Tcl_Eval(interp, buf);
@@ -136,7 +136,7 @@ tcl_eval(Tcp_Interp interp, const char *cmd)
 #define Tcl_Eval tcl_eval
 
 static int
-tcl_global_eval(Tcp_Interp *interp, const char *cmd)
+tcl_global_eval(Tcl_Interp *interp, const char *cmd)
 {
     char *buf = strdup(cmd);
     const int ret = Tcl_GlobalEval(interp, buf);
diff --git a/ext/zlib/zlib.c b/ext/zlib/zlib.c
index c54e83eac0..68d947d052 100644
--- a/ext/zlib/zlib.c
+++ b/ext/zlib/zlib.c
@@ -2983,7 +2983,7 @@ gzreader_skip_linebreaks(struct gzfile *gz)
 }
 
 static void
-rscheck(char *rsptr, long rslen, VALUE rs)
+rscheck(const char *rsptr, long rslen, VALUE rs)
 {
     if (RSTRING(rs)->ptr != rsptr && RSTRING(rs)->len != rslen)
 	rb_raise(rb_eRuntimeError, "rs modified");