diff --git a/src/cmd/ksh93/TYPES b/src/cmd/ksh93/TYPES
index 8a02131fa35e..ac478b1ab1fe 100644
--- a/src/cmd/ksh93/TYPES
+++ b/src/cmd/ksh93/TYPES
@@ -1,11 +1,10 @@
+### User-defined variable types in ksh93 ###
 
-The ability for users to define types has been added to ksh93t.
-Here is a quick summary of how types are defined and used in ksh93t.
-This is still a work in progress so some changes and additions
-are likely.
+The ability for users to define types is available as of ksh version 93t.
+Here is an overview of how types are defined and used in ksh93.
 
-A type can be defined either by a shared library or by using the new
-typeset -T option to the shell.  The method for defining types via
+A type can be defined either by a shared library or by using the -T option
+option to the shell's typeset command.  The method for defining types via
 a shared library is not described here.  However, the source file
 bltins/enum.c is an example of a builtin that creates enumeration types.
 
diff --git a/src/cmd/ksh93/bltins/cd_pwd.c b/src/cmd/ksh93/bltins/cd_pwd.c
index 5cc3d4fc4d0c..eaf49f15e60c 100644
--- a/src/cmd/ksh93/bltins/cd_pwd.c
+++ b/src/cmd/ksh93/bltins/cd_pwd.c
@@ -221,7 +221,7 @@ int	b_cd(int argc, char *argv[],Shbltin_t *context)
 	if(*dp && (*dp!='.'||dp[1]) && strchr(dir,'/'))
 		sfputr(sfstdout,dir,'\n');
 	nv_putval(opwdnod,oldpwd,NV_RDONLY);
-	free((void*)sh.pwd);
+	free(sh.pwd);
 	if(*dir == '/')
 	{
 		size_t len = strlen(dir);
diff --git a/src/cmd/ksh93/bltins/misc.c b/src/cmd/ksh93/bltins/misc.c
index 7b1ab4fc2c47..cb7e883bf239 100644
--- a/src/cmd/ksh93/bltins/misc.c
+++ b/src/cmd/ksh93/bltins/misc.c
@@ -148,7 +148,7 @@ int    b_exec(int argc,char *argv[], Shbltin_t *context)
 		sh_onstate(SH_EXEC);
 		if(sh.subshell && !sh.subshare)
 		{
-			struct dolnod *dp = stkalloc(sh.stk, sizeof(struct dolnod) + ARG_SPARE*sizeof(char*) + argc*sizeof(char*));;
+			struct dolnod *dp = stkalloc(sh.stk, sizeof(struct dolnod) + ARG_SPARE*sizeof(char*) + argc*sizeof(char*));
 			struct comnod *t = stkalloc(sh.stk,sizeof(struct comnod));
 			memset(t, 0, sizeof(struct comnod));
 			dp->dolnum = argc;
diff --git a/src/cmd/ksh93/bltins/whence.c b/src/cmd/ksh93/bltins/whence.c
index 0d07a566c7b4..a440c44a5ab9 100644
--- a/src/cmd/ksh93/bltins/whence.c
+++ b/src/cmd/ksh93/bltins/whence.c
@@ -2,7 +2,7 @@
 *                                                                      *
 *               This software is part of the ast package               *
 *          Copyright (c) 1982-2012 AT&T Intellectual Property          *
-*          Copyright (c) 2020-2023 Contributors to ksh 93u+m           *
+*          Copyright (c) 2020-2024 Contributors to ksh 93u+m           *
 *                      and is licensed under the                       *
 *                 Eclipse Public License, Version 2.0                  *
 *                                                                      *
@@ -322,7 +322,7 @@ static int whence(char **argv, int flags)
 					sfputr(sfstdout,is_pathbound_builtin ? "builtin" : "file",'\n');
 				else
 					sfputr(sfstdout,sh_fmtq(cp),'\n');
-				free((char*)cp);
+				free(cp);
 			}
 			else if(aflag<=1) 
 			{
diff --git a/src/cmd/ksh93/edit/history.c b/src/cmd/ksh93/edit/history.c
index c3e2b8a0aca1..63576020199b 100644
--- a/src/cmd/ksh93/edit/history.c
+++ b/src/cmd/ksh93/edit/history.c
@@ -378,7 +378,7 @@ void hist_close(History_t *hp)
 		sfclose(hp->auditfp);
 	}
 #endif /* SHOPT_AUDIT */
-	free((char*)hp);
+	free(hp);
 	hist_ptr = 0;
 	sh.hist_ptr = 0;
 #if SHOPT_ACCTFILE
@@ -480,7 +480,7 @@ static History_t* hist_trim(History_t *hp, int n)
 	}
 	hist_cancel(hist_new);
 	sfclose(hist_old->histfp);
-	free((char*)hist_old);
+	free(hist_old);
 	return hist_ptr = hist_new;
 }
 
diff --git a/src/cmd/ksh93/include/argnod.h b/src/cmd/ksh93/include/argnod.h
index c52008e81ccc..dfeda66c2847 100644
--- a/src/cmd/ksh93/include/argnod.h
+++ b/src/cmd/ksh93/include/argnod.h
@@ -74,7 +74,7 @@ struct dolnod
 	int		dolmax;		/* size of dolval array */
 	int		dolnum;		/* number of elements */
 	int		dolbot;		/* current first element */
-	struct dolnod	*dolnxt;	/* used when list are chained */
+	struct dolnod	*dolnxt;	/* used when lists are chained */
 	char		*dolval[1];	/* array of value pointers */
 };
 
diff --git a/src/cmd/ksh93/include/shnodes.h b/src/cmd/ksh93/include/shnodes.h
index caace0ecfda3..a2d95679368b 100644
--- a/src/cmd/ksh93/include/shnodes.h
+++ b/src/cmd/ksh93/include/shnodes.h
@@ -2,7 +2,7 @@
 *                                                                      *
 *               This software is part of the ast package               *
 *          Copyright (c) 1982-2012 AT&T Intellectual Property          *
-*          Copyright (c) 2020-2023 Contributors to ksh 93u+m           *
+*          Copyright (c) 2020-2024 Contributors to ksh 93u+m           *
 *                      and is licensed under the                       *
 *                 Eclipse Public License, Version 2.0                  *
 *                                                                      *
diff --git a/src/cmd/ksh93/sh/array.c b/src/cmd/ksh93/sh/array.c
index e7022075e752..5485f2bb06d7 100644
--- a/src/cmd/ksh93/sh/array.c
+++ b/src/cmd/ksh93/sh/array.c
@@ -783,7 +783,7 @@ static void array_copytree(Namval_t *np, Namval_t *mp)
 	nv_offattr(np,NV_ARRAY);
 	nv_clone(np,mp,0);
 	if(np->nvalue.cp && !nv_isattr(np,NV_NOFREE))
-		free((void*)np->nvalue.cp);
+		free(np->nvalue.cp);
 	np->nvalue.cp = 0;
 	np->nvalue.up = &mp->nvalue;
 	fp->nofree  &= ~1;
diff --git a/src/cmd/ksh93/sh/fcin.c b/src/cmd/ksh93/sh/fcin.c
index f5c6622f82dc..91d0d6092504 100644
--- a/src/cmd/ksh93/sh/fcin.c
+++ b/src/cmd/ksh93/sh/fcin.c
@@ -55,7 +55,7 @@ int	fcfopen(Sfio_t* f)
 	n = sfvalue(f);
 	fcrestore(&save);
 	sfread(f,buff,0);
-	_Fcin.fcoff = sftell(f);;
+	_Fcin.fcoff = sftell(f);
 	buff = (char*)sfreserve(f,SFIO_UNBOUND,SFIO_LOCKR);
 	_Fcin.fclast = (_Fcin.fcptr=_Fcin.fcbuff=(unsigned char*)buff)+n;
 	if(sffileno(f) >= 0)
diff --git a/src/cmd/ksh93/sh/main.c b/src/cmd/ksh93/sh/main.c
index 64aadb4d2a73..4bd97845d295 100644
--- a/src/cmd/ksh93/sh/main.c
+++ b/src/cmd/ksh93/sh/main.c
@@ -804,7 +804,7 @@ static void fixargs(char **argv, int mode)
 			/* Move the environment to make space for a larger command line buffer */
 			for(i=0; environ[i]; i++)
 			{
-				buffsize += strlen(environ[i]) + 1;;
+				buffsize += strlen(environ[i]) + 1;
 				environ[i] = sh_strdup(environ[i]);
 			}
 		}
diff --git a/src/cmd/ksh93/sh/name.c b/src/cmd/ksh93/sh/name.c
index 25d383b872f5..df36f4783a91 100644
--- a/src/cmd/ksh93/sh/name.c
+++ b/src/cmd/ksh93/sh/name.c
@@ -1666,7 +1666,7 @@ void nv_putval(Namval_t *np, const char *string, int flags)
 	if(flags&(NV_NOREF|NV_NOFREE))
 	{
 		if(np->nvalue.cp && np->nvalue.cp!=sp && !nv_isattr(np,NV_NOFREE)) 
-			free((void*)np->nvalue.cp);
+			free(np->nvalue.cp);
 		np->nvalue.cp = (char*)sp;
 		nv_setattr(np,(flags&~NV_RDONLY)|NV_NOFREE);
 		return;
@@ -1939,7 +1939,7 @@ void nv_putval(Namval_t *np, const char *string, int flags)
 				{
 					if(tofree)
 					{
-						free((void*)tofree);
+						free(tofree);
 						nv_offattr(np,NV_NOFREE);
 					}
 					up->cp = sp;
@@ -2042,7 +2042,7 @@ void nv_putval(Namval_t *np, const char *string, int flags)
 		if(flags&NV_APPEND)
 			stkseek(sh.stk,offset);
 		if(tofree && tofree!=Empty && tofree!=AltEmpty)
-			free((void*)tofree);
+			free(tofree);
 	}
 	if(!was_local && ((flags&NV_EXPORT) || nv_isattr(np,NV_EXPORT)))
 		env_change();
@@ -2484,7 +2484,7 @@ void	_nv_unset(Namval_t *np,int flags)
 	if(up && up->cp)
 	{
 		if(up->cp!=Empty && up->cp!=AltEmpty && !nv_isattr(np, NV_NOFREE))
-			free((void*)up->cp);
+			free(up->cp);
 		up->cp = 0;
 	}
 done:
diff --git a/src/cmd/ksh93/sh/nvtype.c b/src/cmd/ksh93/sh/nvtype.c
index 10e0799ac317..8b302a406f8d 100644
--- a/src/cmd/ksh93/sh/nvtype.c
+++ b/src/cmd/ksh93/sh/nvtype.c
@@ -1133,7 +1133,7 @@ Namval_t *nv_mktype(Namval_t **nodes, int numnodes)
 				else if(nv_isattr(np,NV_LJUST|NV_RJUST))
 					memset((char*)nq->nvalue.cp,' ',dsize);
 				if(!j)
-					free((void*)np->nvalue.cp);
+					free(np->nvalue.cp);
 			}
 			if(!nq->nvalue.cp && nq->nvfun== &pp->childfun.fun)
 			{
@@ -1327,7 +1327,7 @@ int nv_settype(Namval_t* np, Namval_t *tp, int flags)
 		np->nvalue.up = 0;
 		nv_clone(tp,np,flags|NV_NOFREE);
 		if(np->nvalue.cp && np->nvalue.cp!=Empty && !nv_isattr(np,NV_NOFREE))
-			free((void*)np->nvalue.cp);
+			free(np->nvalue.cp);
 		np->nvalue.up = 0;
 		nofree = ap->hdr.nofree;
 		ap->hdr.nofree = 0;
diff --git a/src/cmd/ksh93/sh/path.c b/src/cmd/ksh93/sh/path.c
index cda76140379d..10b9700a1d1e 100644
--- a/src/cmd/ksh93/sh/path.c
+++ b/src/cmd/ksh93/sh/path.c
@@ -212,7 +212,7 @@ char *path_pwd(void)
 	{
 		if(*sh.pwd=='/')
 			return (char*)sh.pwd;
-		free((void*)sh.pwd);
+		free(sh.pwd);
 	}
 	/* First see if PWD variable is correct */
 	pwdnod = sh_scoped(PWDNOD);
diff --git a/src/cmd/ksh93/sh/subshell.c b/src/cmd/ksh93/sh/subshell.c
index a6223117e603..38268abc5633 100644
--- a/src/cmd/ksh93/sh/subshell.c
+++ b/src/cmd/ksh93/sh/subshell.c
@@ -364,7 +364,7 @@ static void nv_restore(struct subshell *sp)
 		else
 			mp->nvalue = np->nvalue;
 		if(nofree && np->nvfun && !np->nvfun->nofree)
-			free((char*)np->nvfun);
+			free(np->nvfun);
 		np->nvfun = 0;
 		if(nv_isattr(mp,NV_EXPORT))
 		{
@@ -836,7 +836,7 @@ Sfio_t *sh_subshell(Shnode_t *t, volatile int flags, int comsub)
 		else if(sp->pwd && strcmp(sp->pwd,sh.pwd))
 			path_newdir(sh.pathlist);
 		if(sh.pwd)
-			free((void*)sh.pwd);
+			free(sh.pwd);
 		sh.pwd = sp->pwd;
 #if _lib_fchdir
 		if(sp->pwdclose)
@@ -918,7 +918,7 @@ Sfio_t *sh_subshell(Shnode_t *t, volatile int flags, int comsub)
 			case 2:
 				/* reinit PWD as it will be wrong */
 				if(sh.pwd)
-					free((void*)sh.pwd);
+					free(sh.pwd);
 				sh.pwd = NULL;
 				path_pwd();
 				errno = saveerrno;
diff --git a/src/cmd/ksh93/sh/tdump.c b/src/cmd/ksh93/sh/tdump.c
index 9b31fb299a18..e36db90340bb 100644
--- a/src/cmd/ksh93/sh/tdump.c
+++ b/src/cmd/ksh93/sh/tdump.c
@@ -2,7 +2,7 @@
 *                                                                      *
 *               This software is part of the ast package               *
 *          Copyright (c) 1982-2011 AT&T Intellectual Property          *
-*          Copyright (c) 2020-2023 Contributors to ksh 93u+m           *
+*          Copyright (c) 2020-2024 Contributors to ksh 93u+m           *
 *                      and is licensed under the                       *
 *                 Eclipse Public License, Version 2.0                  *
 *                                                                      *
diff --git a/src/cmd/ksh93/tests/attributes.sh b/src/cmd/ksh93/tests/attributes.sh
index 55083c3eb23d..52ed9f0a31a5 100755
--- a/src/cmd/ksh93/tests/attributes.sh
+++ b/src/cmd/ksh93/tests/attributes.sh
@@ -2,7 +2,7 @@
 #                                                                      #
 #               This software is part of the ast package               #
 #          Copyright (c) 1982-2012 AT&T Intellectual Property          #
-#          Copyright (c) 2020-2023 Contributors to ksh 93u+m           #
+#          Copyright (c) 2020-2024 Contributors to ksh 93u+m           #
 #                      and is licensed under the                       #
 #                 Eclipse Public License, Version 2.0                  #
 #                                                                      #
diff --git a/src/cmd/ksh93/tests/builtins.sh b/src/cmd/ksh93/tests/builtins.sh
index 0ac6bb8b7931..27eeeafeb798 100755
--- a/src/cmd/ksh93/tests/builtins.sh
+++ b/src/cmd/ksh93/tests/builtins.sh
@@ -1693,7 +1693,7 @@ exp='\\ \\\\'
 	"(expected $(printf %q "$exp"), got $(printf %q "$got"))"
 
 # ======
-case $(PATH=/opt/ast/bin:$PATH; exec cat '--???SECTION' 2>&1) in
+case $(PATH=/opt/ast/bin:$PATH; exec cat '--???SECTION' </dev/null 2>&1) in
 1)	err_exit "'exec' runs non-external command" ;;
 esac
 
diff --git a/src/lib/libast/cdt/dtlist.c b/src/lib/libast/cdt/dtlist.c
index 8438ad145dbb..217054b9ff81 100644
--- a/src/lib/libast/cdt/dtlist.c
+++ b/src/lib/libast/cdt/dtlist.c
@@ -2,7 +2,7 @@
 *                                                                      *
 *               This software is part of the ast package               *
 *          Copyright (c) 1985-2012 AT&T Intellectual Property          *
-*          Copyright (c) 2020-2023 Contributors to ksh 93u+m           *
+*          Copyright (c) 2020-2024 Contributors to ksh 93u+m           *
 *                      and is licensed under the                       *
 *                 Eclipse Public License, Version 2.0                  *
 *                                                                      *
@@ -170,8 +170,7 @@ static void* dtlist(Dt_t* dt, void* obj, int type)
 		goto do_insert;
 	}
 	else if(type&(DT_INSERT|DT_INSTALL|DT_APPEND|DT_ATTACH))
-	{
-		if(!(r = _dtmake(dt, obj, type)) )
+	{	if(!(r = _dtmake(dt, obj, type)) )
 			DTRETURN(obj, NULL);
 		dt->data->size += 1;
 
diff --git a/src/lib/libast/cdt/dttree.c b/src/lib/libast/cdt/dttree.c
index 4767157524d1..92f82f7307b5 100644
--- a/src/lib/libast/cdt/dttree.c
+++ b/src/lib/libast/cdt/dttree.c
@@ -2,7 +2,7 @@
 *                                                                      *
 *               This software is part of the ast package               *
 *          Copyright (c) 1985-2012 AT&T Intellectual Property          *
-*          Copyright (c) 2020-2023 Contributors to ksh 93u+m           *
+*          Copyright (c) 2020-2024 Contributors to ksh 93u+m           *
 *                      and is licensed under the                       *
 *                 Eclipse Public License, Version 2.0                  *
 *                                                                      *
@@ -638,10 +638,6 @@ static Dtmethod_t	_Dtobag =  { dttree, DT_OBAG, treeevent, "Dtobag" };
 Dtmethod_t		*Dtoset	= &_Dtoset;
 Dtmethod_t		*Dtobag = &_Dtobag;
 
-/* backward compatibility */
-#undef	Dttree
-Dtmethod_t		*Dttree = &_Dtoset;
-
 #ifdef NoF
 NoF(dttree)
 #endif
diff --git a/src/lib/libast/features/lib b/src/lib/libast/features/lib
index ef4ca3f9600f..cc774f61a13d 100644
--- a/src/lib/libast/features/lib
+++ b/src/lib/libast/features/lib
@@ -23,7 +23,7 @@ dat	_tzname,tzname
 
 lib	BSDsetpgrp
 lib	_cleanup
-lib	bcopy,bzero,catclose,catgets,catopen,confstr,dirread,dup2
+lib	bcopy,bzero,confstr,dirread,dup2
 lib	execlp,execve,execvp,execvpe
 lib	fchmod,fcntl,fmtmsg,fnmatch,fork,fsync
 lib	getconf,getdents,getdirentries,getdtablesize,getdate
diff --git a/src/lib/libast/features/nl_types b/src/lib/libast/features/nl_types
index 4957294504e0..ca18cb9d4f58 100644
--- a/src/lib/libast/features/nl_types
+++ b/src/lib/libast/features/nl_types
@@ -57,4 +57,7 @@ tst	output{
 		printf("\n");
 		return 0;
 	}
+}end fail{
+	echo "$0: Output block failed to compile. Export IFFEFLAGS=-d1 to debug." >&2
+	exit 1
 }end
diff --git a/src/lib/libast/hash/hashlook.c b/src/lib/libast/hash/hashlook.c
index 6ed4abbcb726..4717bf4f2743 100644
--- a/src/lib/libast/hash/hashlook.c
+++ b/src/lib/libast/hash/hashlook.c
@@ -2,7 +2,7 @@
 *                                                                      *
 *               This software is part of the ast package               *
 *          Copyright (c) 1985-2011 AT&T Intellectual Property          *
-*          Copyright (c) 2020-2023 Contributors to ksh 93u+m           *
+*          Copyright (c) 2020-2024 Contributors to ksh 93u+m           *
 *                      and is licensed under the                       *
 *                 Eclipse Public License, Version 2.0                  *
 *                                                                      *
@@ -191,7 +191,7 @@ hashlook(Hash_table_t* tab, const char* name, long flags, const char* value)
 						if (name)
 						{
 							if (tab->root->local->region) (*tab->root->local->region)(tab->root->local->handle, (char*)name, 0, 0);
-							else free((char*)name);
+							else free(name);
 						}
 					}
 				}
@@ -233,7 +233,7 @@ hashlook(Hash_table_t* tab, const char* name, long flags, const char* value)
 				{
 					b->hash &= ~HASH_FREENAME;
 					if (tab->root->local->region) (*tab->root->local->region)(tab->root->local->handle, (char*)name, 0, 0);
-					else free((char*)name);
+					else free(name);
 				}
 				tab->buckets--;
 				tab->table[n] = b->next;
diff --git a/src/lib/libast/regex/regclass.c b/src/lib/libast/regex/regclass.c
index 30528a0fb896..b56b74a483d7 100644
--- a/src/lib/libast/regex/regclass.c
+++ b/src/lib/libast/regex/regclass.c
@@ -228,7 +228,7 @@ regclass(const char* s, char** e)
 		cp->size = 0;
 		if (!streq(cp->name, s))
 		{
-			free((char*)cp->name);
+			free(cp->name);
 			cp->name = 0;
 		}
 	}
@@ -241,7 +241,7 @@ regclass(const char* s, char** e)
 	/* mvs.390 needs the (char*) cast -- barf */
 	if (!(cp->wtype = wctype((char*)cp->name)))
 	{
-		free((char*)cp->name);
+		free(cp->name);
 		cp->name = 0;
 		return NULL;
 	}
diff --git a/src/lib/libast/sfio/sfmode.c b/src/lib/libast/sfio/sfmode.c
index 28624f13279b..058f764fdf48 100644
--- a/src/lib/libast/sfio/sfmode.c
+++ b/src/lib/libast/sfio/sfmode.c
@@ -255,7 +255,7 @@ static int _sfpmode(Sfio_t* f, int type)
 		p->ndata = f->endb-f->next;
 		if(p->ndata > p->size)
 		{	if(p->rdata)
-				free((char*)p->rdata);
+				free(p->rdata);
 			if((p->rdata = (uchar*)malloc(p->ndata)) )
 				p->size = p->ndata;
 			else