Fix various possible uses of uninitialised variables

Patch from OpenSUSE, slightly adapted for 93u+m. Source:
https://build.opensuse.org/package/view_file/shells/ksh/ksh93-uninitialized.dif

src/cmd/ksh93/sh/init.c

@@ -1176,7 +1176,7 @@ Shell_t *sh_init(register int argc,register char *argv[], Shinit_f userinit)
 	static int beenhere;
 	Shell_t	*shp;
 	register int n;
-	int type;
+	int type = 0;
 	char *save_envmarker;
 	static char *login_files[2];
 	memfatal();
@@ -1846,7 +1846,7 @@ Dt_t *sh_inittree(Shell_t *shp,const struct shtable2 *name_vals)
 	register const struct shtable2 *tp;
 	register unsigned n = 0;
 	register Dt_t *treep;
-	Dt_t *base_treep, *dict;
+	Dt_t *base_treep, *dict = 0;
 	for(tp=name_vals;*tp->sh_name;tp++)
 		n++;
 	np = (Namval_t*)calloc(n,sizeof(Namval_t));

src/cmd/ksh93/sh/macro.c

@@ -1803,7 +1803,7 @@ retry2:
 		int ofs_size = 0;
 		regoff_t match[2*(MATCH_MAX+1)];
 		int nmatch, nmatch_prev, vsize_last;
-		char *vlast;
+		char *vlast = NIL(char*);
 		while(1)
 		{
 			if(!v)

src/cmd/ksh93/sh/name.c

@@ -1305,7 +1305,7 @@ Namval_t *nv_open(const char *name, Dt_t *root, int flags)
 	const char		*msg = e_varname;
 	char			*fname = 0;
 	int			offset = staktell();
-	Dt_t			*funroot;
+	Dt_t			*funroot = NIL(Dt_t*);
 #if NVCACHE
 	struct Cache_entry	*xp;
 #endif
@@ -1779,7 +1779,7 @@ void nv_putval(register Namval_t *np, const char *string, int flags)
 	else
 	{
 		const char *tofree=0;
-		int offset,append;
+		int offset=0,append;
 #if _lib_pathnative
 		char buff[PATH_MAX];
 #endif /* _lib_pathnative */

src/cmd/ksh93/sh/nvdisc.c

@@ -453,7 +453,7 @@ static Sfdouble_t lookupn(Namval_t *np, Namfun_t *handle)
 char *nv_setdisc(register Namval_t* np,register const char *event,Namval_t *action,register Namfun_t *fp)
 {
 	register struct vardisc *vp = (struct vardisc*)np->nvfun;
-	register int type;
+	register int type = -1;
 	char *empty = "";
 	while(vp)
 	{
@@ -509,6 +509,8 @@ char *nv_setdisc(register Namval_t* np,register const char *event,Namval_t *acti
 		}
 		return(NIL(char*));
 	}
+	if (type < 0)
+		return(NIL(char*));
 	/* Handle GET/SET/APPEND/UNSET disc */
 	if(vp && vp->fun.disc->putval!=assign)
 		vp = 0;

src/cmd/ksh93/sh/nvtree.c

@@ -557,7 +557,7 @@ void nv_outnode(Namval_t *np, Sfio_t* out, int indent, int special)
 	char		*fmtq,*ep,*xp;
 	Namval_t	*mp;
 	Namarr_t	*ap = nv_arrayptr(np);
-	int		scan,tabs=0,c,more,associative = 0;
+	int		scan=0,tabs=0,c,more,associative = 0;
 	int		saveI = Indent;
 	Indent = indent;
 	if(ap)
@@ -670,7 +670,7 @@ void nv_outnode(Namval_t *np, Sfio_t* out, int indent, int special)
 
 static void outval(char *name, const char *vname, struct Walk *wp)
 {
-	register Namval_t *np, *nq, *last_table=wp->shp->last_table;
+	register Namval_t *np, *nq=0, *last_table=wp->shp->last_table;
         register Namfun_t *fp;
 	int isarray=0, special=0,mode=0;
 	if(*name!='.' || vname[strlen(vname)-1]==']')

src/cmd/ksh93/sh/nvtype.c

@@ -826,9 +826,10 @@ void nv_newtype(Namval_t *mp)
 Namval_t *nv_mktype(Namval_t **nodes, int numnodes)
 {
 	Namval_t	*mp=nodes[0], *bp=0, *np, *nq, **mnodes=nodes;
-	int		i,j,k,m,n,nd=0,nref=0,iref=0,inherit=0;
+	int		i,j,k,nd=0,nref=0,iref=0,inherit=0;
 	int		size=sizeof(NV_DATA), dsize=0, nnodes;
-	size_t		offset=0;
+	size_t		offset=0,m;
+	ssize_t		n;
 	char		*name=0, *cp, *sp, **help;
 	Namtype_t	*pp,*qp=0,*dp,*tp;
 	Dt_t		*root = nv_dict(mp);
@@ -841,6 +842,7 @@ Namval_t *nv_mktype(Namval_t **nodes, int numnodes)
 		_nv_unset(nodes[0],NV_RDONLY);
 		errormsg(SH_DICT,ERROR_exit(1),e_badtypedef,cp);
 	}
+	n=strlen(nodes[1]->nvname);
 	for(nnodes=1,i=1; i <numnodes; i++)
 	{
 		np=nodes[i];

src/cmd/ksh93/sh/parse.c

@@ -302,7 +302,7 @@ static Shnode_t *getanode(Lex_t *lp, struct argnod *ap)
  */
 static Shnode_t	*makelist(Lex_t *lexp, int type, Shnode_t *l, Shnode_t *r)
 {
-	register Shnode_t	*t;
+	register Shnode_t	*t = NIL(Shnode_t*);
 	if(!l || !r)
 		sh_syntax(lexp);
 	else
@@ -808,7 +808,7 @@ static Shnode_t *funct(Lex_t *lexp)
 		{
 			struct comnod	*ac;
 			char		*cp, **argv, **argv0;
-			int		c;
+			int		c=-1;
 			t->funct.functargs = ac = (struct comnod*)simple(lexp,SH_NOIO|SH_FUNDEF,NIL(struct ionod*));
 			if(ac->comset || (ac->comtyp&COMSCAN))
 				errormsg(SH_DICT,ERROR_exit(3),e_lexsyntax4,lexp->sh->inlineno);

src/cmd/ksh93/sh/xec.c

@@ -1426,7 +1426,7 @@ int sh_exec(register const Shnode_t *t, int flags)
 					Namval_t node;
 #endif /* SHOPT_NAMESPACE */
 					struct Namref	nr;
-					long		mode;
+					long		mode = 0;
 					register struct slnod *slp;
 					if(!np->nvalue.ip)
 					{
@@ -1771,8 +1771,8 @@ int sh_exec(register const Shnode_t *t, int flags)
 		     * don't create a new process, just
 		     * save and restore io-streams
 		     */
-			pid_t	pid;
-			int 	jmpval, waitall;
+			pid_t	pid = 0;
+			int 	jmpval, waitall = 0;
 			int 	simple = (t->fork.forktre->tre.tretyp&COMMSK)==TCOM;
 			struct checkpt *buffp = (struct checkpt*)stkalloc(shp->stk,sizeof(struct checkpt));
 			if(shp->subshell)
@@ -2162,7 +2162,7 @@ int sh_exec(register const Shnode_t *t, int flags)
 			Shnode_t *tt = t->wh.whtre;
 #if SHOPT_FILESCAN
 			Sfio_t *iop=0;
-			int savein;
+			int savein=-1;
 #endif /*SHOPT_FILESCAN*/
 #if SHOPT_OPTIMIZE
 			int  jmpval = ((struct checkpt*)shp->jmplist)->mode;
@@ -2579,7 +2579,7 @@ int sh_exec(register const Shnode_t *t, int flags)
 			else
 			{
 				register int traceon=0;
-				register char *right;
+				register char *right = 0;
 				register char *trap;
 				char *argv[6];
 				n = type>>TSHIFT;
@@ -2613,7 +2613,7 @@ int sh_exec(register const Shnode_t *t, int flags)
 				}
 				else if(type&TBINARY)
 				{
-					char *op;
+					char *op = 0;
 					int pattern = 0;
 					if(trap || traceon)
 						op = (char*)(shtab_testops+(n&037)-1)->sh_name;
@@ -3277,11 +3277,11 @@ static void sh_funct(Shell_t *shp,Namval_t *np,int argn, char *argv[],struct arg
 int sh_fun(Namval_t *np, Namval_t *nq, char *argv[])
 {
 	Shell_t		*shp = sh_getinterp();
-	register int offset;
+	register int offset = 0;
 	register char *base;
 	Namval_t node;
 	struct Namref	nr;
-	long		mode;
+	long		mode = 0;
 	char		*prefix = shp->prefix;
 	int n=0;
 	char *av[3];