Consting and localizing: Part LXVIII

Message-ID: <20051104211256.GA12651@petdance.com>

p4raw-id: //depot/perl@26028

10 files changed, 126 insertions, 153 deletions

diff --git a/deb.c b/deb.c
index 878b7cb9c5..a3b67b4168 100644
--- a/deb.c
+++ b/deb.c
@@ -172,7 +172,7 @@ Perl_deb_stack_all(pTHX)
 {
 #ifdef DEBUGGING
     I32		 ix, si_ix;
-    PERL_SI	 *si;
+    const PERL_SI *si;
 
     /* rewind to start of chain */
     si = PL_curstackinfo;
@@ -183,13 +183,13 @@ Perl_deb_stack_all(pTHX)
     for (;;)
     {
         const int si_name_ix = si->si_type+1; /* -1 is a valid index */
-        const char *si_name = (si_name_ix>= sizeof(si_names)) ? "????" : si_names[si_name_ix];
+        const char * const si_name = (si_name_ix>= sizeof(si_names)) ? "????" : si_names[si_name_ix];
 	PerlIO_printf(Perl_debug_log, "STACK %"IVdf": %s\n",
 						(IV)si_ix, si_name);
 
 	for (ix=0; ix<=si->si_cxix; ix++) {
 
-	    const PERL_CONTEXT *cx = &(si->si_cxstack[ix]);
+	    const PERL_CONTEXT * const cx = &(si->si_cxstack[ix]);
 	    PerlIO_printf(Perl_debug_log,
 		    "  CX %"IVdf": %-6s => ",
 		    (IV)ix, PL_block_type[CxTYPE(cx)]
@@ -206,9 +206,8 @@ Perl_deb_stack_all(pTHX)
 		 */
 
 		I32 i, stack_min, stack_max, mark_min, mark_max;
-		PERL_CONTEXT *cx_n;
-		PERL_SI      *si_n;
-		OP	     *retop;
+		const PERL_CONTEXT *cx_n;
+		const PERL_SI *si_n;
 
 		cx_n = Null(PERL_CONTEXT*);
 
@@ -270,7 +269,7 @@ Perl_deb_stack_all(pTHX)
 		if (CxTYPE(cx) == CXt_EVAL || CxTYPE(cx) == CXt_SUB
 			|| CxTYPE(cx) == CXt_FORMAT)
 		{
-		    retop = (CxTYPE(cx) == CXt_EVAL)
+		    const OP * const retop = (CxTYPE(cx) == CXt_EVAL)
 			    ? cx->blk_eval.retop : cx->blk_sub.retop;
 
 		    PerlIO_printf(Perl_debug_log, "  retop=%s\n",
diff --git a/embed.fnc b/embed.fnc
index 747426d048..5ea795f4f0 100644
--- a/embed.fnc
+++ b/embed.fnc
@@ -1373,6 +1373,7 @@ sn	|NV|mulexp10	|NV value|I32 exponent
 
 #if defined(PERL_IN_UTF8_C) || defined(PERL_DECL_PROT)
 s	|STRLEN	|is_utf8_char_slow|NN const U8 *s|const STRLEN len
+spR	|bool	|is_utf8_common	|NN const U8 *const p|NN SV **swash|NN const char * const swashname
 #endif
 
 START_EXTERN_C
diff --git a/embed.h b/embed.h
index a303652de6..d15e9ab8ba 100644
--- a/embed.h
+++ b/embed.h
@@ -1409,6 +1409,7 @@
 #if defined(PERL_IN_UTF8_C) || defined(PERL_DECL_PROT)
 #ifdef PERL_CORE
 #define is_utf8_char_slow	S_is_utf8_char_slow
+#define is_utf8_common		S_is_utf8_common
 #endif
 #endif
 #define sv_setsv_flags		Perl_sv_setsv_flags
@@ -3398,6 +3399,7 @@
 #if defined(PERL_IN_UTF8_C) || defined(PERL_DECL_PROT)
 #ifdef PERL_CORE
 #define is_utf8_char_slow(a,b)	S_is_utf8_char_slow(aTHX_ a,b)
+#define is_utf8_common(a,b,c)	S_is_utf8_common(aTHX_ a,b,c)
 #endif
 #endif
 #define sv_setsv_flags(a,b,c)	Perl_sv_setsv_flags(aTHX_ a,b,c)
diff --git a/locale.c b/locale.c
index 3b854c4a01..e7572cfb60 100644
--- a/locale.c
+++ b/locale.c
@@ -53,7 +53,7 @@
 STATIC char *
 S_stdize_locale(pTHX_ char *locs)
 {
-    const char *s = strchr(locs, '=');
+    const char * const s = strchr(locs, '=');
     bool okay = TRUE;
 
     if (s) {
@@ -82,9 +82,8 @@ Perl_set_numeric_radix(pTHX)
 {
 #ifdef USE_LOCALE_NUMERIC
 # ifdef HAS_LOCALECONV
-    struct lconv* lc;
+    const struct lconv* const lc = localeconv();
 
-    lc = localeconv();
     if (lc && lc->decimal_point) {
 	if (lc->decimal_point[0] == '.' && lc->decimal_point[1] == 0) {
 	    SvREFCNT_dec(PL_numeric_radix_sv);
@@ -254,10 +253,10 @@ Perl_init_i18nl10n(pTHX_ int printwarn)
     char *curnum     = NULL;
 #endif /* USE_LOCALE_NUMERIC */
 #ifdef __GLIBC__
-    char *language   = PerlEnv_getenv("LANGUAGE");
+    char * const language   = PerlEnv_getenv("LANGUAGE");
 #endif
-    char *lc_all     = PerlEnv_getenv("LC_ALL");
-    char *lang       = PerlEnv_getenv("LANG");
+    char * const lc_all     = PerlEnv_getenv("LC_ALL");
+    char * const lang       = PerlEnv_getenv("LANG");
     bool setlocale_failure = FALSE;
 
 #ifdef LOCALE_ENVIRON_REQUIRED
diff --git a/pp_sys.c b/pp_sys.c
index 5c1ebd2b1c..4d22a8244e 100644
--- a/pp_sys.c
+++ b/pp_sys.c
@@ -330,10 +330,7 @@ PP(pp_backtick)
 	mode = "rt";
     fp = PerlProc_popen(tmps, mode);
     if (fp) {
-        const char *type = NULL;
-	if (PL_curcop->cop_io) {
-	    type = SvPV_nolen_const(PL_curcop->cop_io);
-	}
+        const char * const type = PL_curcop->cop_io ? SvPV_nolen_const(PL_curcop->cop_io) : NULL;
 	if (type && *type)
 	    PerlIO_apply_layers(aTHX_ fp,mode,type);
 
@@ -488,11 +485,11 @@ PP(pp_die)
 	    if (!multiarg)
 		SvSetSV(error,tmpsv);
 	    else if (sv_isobject(error)) {
-		HV *stash = SvSTASH(SvRV(error));
-		GV *gv = gv_fetchmethod(stash, "PROPAGATE");
+		HV * const stash = SvSTASH(SvRV(error));
+		GV * const gv = gv_fetchmethod(stash, "PROPAGATE");
 		if (gv) {
-		    SV *file = sv_2mortal(newSVpv(CopFILE(PL_curcop),0));
-		    SV *line = sv_2mortal(newSVuv(CopLINE(PL_curcop)));
+		    SV * const file = sv_2mortal(newSVpv(CopFILE(PL_curcop),0));
+		    SV * const line = sv_2mortal(newSVuv(CopLINE(PL_curcop)));
 		    EXTEND(SP, 3);
 		    PUSHMARK(SP);
 		    PUSHs(error);
@@ -880,7 +877,7 @@ PP(pp_untie)
 
     if ((mg = SvTIED_mg(sv, how))) {
 	SV * const obj = SvRV(SvTIED_obj(sv, mg));
-	CV *cv = NULL;
+	CV *cv;
         if (obj) {
 	    GV * const gv = gv_fetchmethod_autoload(SvSTASH(obj), "UNTIE", FALSE);
 	    if (gv && isGV(gv) && (cv = GvCV(gv))) {
@@ -1158,12 +1155,10 @@ Perl_setdefout(pTHX_ GV *gv)
 PP(pp_select)
 {
     dSP; dTARGET;
-    GV *egv;
     HV *hv;
-
     GV * const newdefout = (PL_op->op_private > 0) ? ((GV *) POPs) : (GV *) NULL;
+    GV * egv = GvEGV(PL_defoutgv);
 
-    egv = GvEGV(PL_defoutgv);
     if (!egv)
 	egv = PL_defoutgv;
     hv = GvSTASH(egv);
@@ -1775,7 +1770,6 @@ PP(pp_sysread)
 PP(pp_send)
 {
     dVAR; dSP; dMARK; dORIGMARK; dTARGET;
-    GV *gv;
     IO *io;
     SV *bufsv;
     const char *buffer;
@@ -1785,7 +1779,7 @@ PP(pp_send)
     MAGIC *mg;
     const int op_type = PL_op->op_type;
     
-    gv = (GV*)*++MARK;
+    GV *const gv = (GV*)*++MARK;
     if (PL_op->op_type == OP_SYSWRITE
 	&& gv && (io = GvIO(gv))
 	&& (mg = SvTIED_mg((SV*)io, PERL_MAGIC_tiedscalar)))
@@ -2009,17 +2003,16 @@ PP(pp_tell)
 PP(pp_sysseek)
 {
     dVAR; dSP;
-    GV *gv;
     IO *io;
     const int whence = POPi;
 #if LSEEKSIZE > IVSIZE
-    Off_t offset = (Off_t)SvNVx(POPs);
+    const Off_t offset = (Off_t)SvNVx(POPs);
 #else
-    Off_t offset = (Off_t)SvIVx(POPs);
+    const Off_t offset = (Off_t)SvIVx(POPs);
 #endif
     MAGIC *mg;
 
-    gv = PL_last_in_gv = (GV*)POPs;
+    GV * const gv = PL_last_in_gv = (GV*)POPs;
 
     if (gv && (io = GvIO(gv))
 	&& (mg = SvTIED_mg((SV*)io, PERL_MAGIC_tiedscalar)))
@@ -2047,7 +2040,7 @@ PP(pp_sysseek)
         if (sought < 0)
             PUSHs(&PL_sv_undef);
         else {
-            SV* sv = sought ?
+            SV* const sv = sought ?
 #if LSEEKSIZE > IVSIZE
                 newSVnv((NV)sought)
 #else
@@ -2068,12 +2061,11 @@ PP(pp_truncate)
      * general one would think that when using large files, off_t is
      * at least as wide as size_t, so using an off_t should be okay. */
     /* XXX Configure probe for the length type of *truncate() needed XXX */
-    Off_t len;
 
 #if Off_t_size > IVSIZE
-    len = (Off_t)POPn;
+    const Off_t len = (Off_t)POPn;
 #else
-    len = (Off_t)POPi;
+    const Off_t len = (Off_t)POPi;
 #endif
     /* Checking for length < 0 is problematic as the type might or
      * might not be signed: if it is not, clever compilers will moan. */
@@ -2110,7 +2102,7 @@ PP(pp_truncate)
 	    }
 	}
 	else {
-	    SV *sv = POPs;
+	    SV * const sv = POPs;
 	    const char *name;
 
 	    if (SvTYPE(sv) == SVt_PVGV) {
@@ -2133,9 +2125,9 @@ PP(pp_truncate)
 	        result = 0;
 #else
 	    {
-	        int tmpfd;
+		const int tmpfd = PerlLIO_open(name, O_RDWR);
 
-		if ((tmpfd = PerlLIO_open(name, O_RDWR)) < 0)
+		if (tmpfd < 0)
 		    result = 0;
 		else {
 		    if (my_chsize(tmpfd, len) < 0)
@@ -2157,13 +2149,13 @@ PP(pp_truncate)
 PP(pp_ioctl)
 {
     dSP; dTARGET;
-    SV *argsv = POPs;
+    SV * const argsv = POPs;
     const unsigned int func = POPu;
     const int optype = PL_op->op_type;
+    GV * const gv = (GV*)POPs;
+    IO * const io = gv ? GvIOn(gv) : Null(IO*);
     char *s;
     IV retval;
-    GV *gv = (GV*)POPs;
-    IO *io = gv ? GvIOn(gv) : 0;
 
     if (!io || !argsv || !IoIFP(io)) {
 	if (ckWARN2(WARN_UNOPENED,WARN_CLOSED))
@@ -2234,16 +2226,11 @@ PP(pp_flock)
 #ifdef FLOCK
     dSP; dTARGET;
     I32 value;
-    int argtype;
-    GV *gv;
     IO *io = NULL;
     PerlIO *fp;
+    const int argtype = POPi;
+    GV * const gv = (MAXARG == 0) ? PL_last_in_gv : (GV*)POPs;
 
-    argtype = POPi;
-    if (MAXARG == 0)
-	gv = PL_last_in_gv;
-    else
-	gv = (GV*)POPs;
     if (gv && (io = GvIO(gv)))
 	fp = IoIFP(io);
     else {
@@ -2273,16 +2260,13 @@ PP(pp_socket)
 {
 #ifdef HAS_SOCKET
     dSP;
-    GV *gv;
-    register IO *io;
-    int protocol = POPi;
-    int type = POPi;
-    int domain = POPi;
+    const int protocol = POPi;
+    const int type = POPi;
+    const int domain = POPi;
+    GV * const gv = (GV*)POPs;
+    register IO * const io = gv ? GvIOn(gv) : NULL;
     int fd;
 
-    gv = (GV*)POPs;
-    io = gv ? GvIOn(gv) : NULL;
-
     if (!gv || !io) {
 	if (ckWARN2(WARN_UNOPENED,WARN_CLOSED))
 	    report_evil_fh(gv, io, PL_op->op_type);
@@ -2326,19 +2310,15 @@ PP(pp_sockpair)
 {
 #if defined (HAS_SOCKETPAIR) || (defined (HAS_SOCKET) && defined(SOCK_DGRAM) && defined(AF_INET) && defined(PF_INET))
     dSP;
-    GV *gv1;
-    GV *gv2;
-    register IO *io1;
-    register IO *io2;
-    int protocol = POPi;
-    int type = POPi;
-    int domain = POPi;
+    const int protocol = POPi;
+    const int type = POPi;
+    const int domain = POPi;
+    GV * const gv2 = (GV*)POPs;
+    GV * const gv1 = (GV*)POPs;
+    register IO * const io1 = gv1 ? GvIOn(gv1) : NULL;
+    register IO * const io2 = gv2 ? GvIOn(gv2) : NULL;
     int fd[2];
 
-    gv2 = (GV*)POPs;
-    gv1 = (GV*)POPs;
-    io1 = gv1 ? GvIOn(gv1) : NULL;
-    io2 = gv2 ? GvIOn(gv2) : NULL;
     if (!gv1 || !gv2 || !io1 || !io2) {
 	if (ckWARN2(WARN_UNOPENED,WARN_CLOSED)) {
 	    if (!gv1 || !io1)
@@ -2395,11 +2375,11 @@ PP(pp_bind)
     extern void GETPRIVMODE();
     extern void GETUSERMODE();
 #endif
-    SV *addrsv = POPs;
+    SV * const addrsv = POPs;
     /* OK, so on what platform does bind modify addr?  */
     const char *addr;
-    GV *gv = (GV*)POPs;
-    register IO *io = GvIOn(gv);
+    GV * const gv = (GV*)POPs;
+    register IO * const io = GvIOn(gv);
     STRLEN len;
     int bind_ok = 0;
 #ifdef MPE
@@ -2451,10 +2431,10 @@ PP(pp_connect)
 {
 #ifdef HAS_SOCKET
     dSP;
-    SV *addrsv = POPs;
+    SV * const addrsv = POPs;
+    GV * const gv = (GV*)POPs;
+    register IO * const io = GvIOn(gv);
     const char *addr;
-    GV *gv = (GV*)POPs;
-    register IO *io = GvIOn(gv);
     STRLEN len;
 
     if (!io || !IoIFP(io))
@@ -2481,9 +2461,9 @@ PP(pp_listen)
 {
 #ifdef HAS_SOCKET
     dSP;
-    int backlog = POPi;
-    GV *gv = (GV*)POPs;
-    register IO *io = gv ? GvIOn(gv) : NULL;
+    const int backlog = POPi;
+    GV * const gv = (GV*)POPs;
+    register IO * const io = gv ? GvIOn(gv) : NULL;
 
     if (!gv || !io || !IoIFP(io))
 	goto nuts;
@@ -2507,8 +2487,6 @@ PP(pp_accept)
 {
 #ifdef HAS_SOCKET
     dSP; dTARGET;
-    GV *ngv;
-    GV *ggv;
     register IO *nstio;
     register IO *gstio;
     char namebuf[MAXPATHLEN];
@@ -2517,11 +2495,10 @@ PP(pp_accept)
 #else
     Sock_size_t len = sizeof namebuf;
 #endif
+    GV * const ggv = (GV*)POPs;
+    GV * const ngv = (GV*)POPs;
     int fd;
 
-    ggv = (GV*)POPs;
-    ngv = (GV*)POPs;
-
     if (!ngv)
 	goto badexit;
     if (!ggv)
@@ -2578,9 +2555,9 @@ PP(pp_shutdown)
 {
 #ifdef HAS_SOCKET
     dSP; dTARGET;
-    int how = POPi;
-    GV *gv = (GV*)POPs;
-    register IO *io = GvIOn(gv);
+    const int how = POPi;
+    GV * const gv = (GV*)POPs;
+    register IO * const io = GvIOn(gv);
 
     if (!io || !IoIFP(io))
 	goto nuts;
@@ -2602,24 +2579,15 @@ PP(pp_ssockopt)
 {
 #ifdef HAS_SOCKET
     dSP;
-    int optype = PL_op->op_type;
-    SV *sv;
+    const int optype = PL_op->op_type;
+    SV * const sv = (optype == OP_GSOCKOPT) ? sv_2mortal(NEWSV(22, 257)) : POPs;
+    const unsigned int optname = (unsigned int) POPi;
+    const unsigned int lvl = (unsigned int) POPi;
+    GV * const gv = (GV*)POPs;
+    register IO * const io = GvIOn(gv);
     int fd;
-    unsigned int optname;
-    unsigned int lvl;
-    GV *gv;
-    register IO *io;
     Sock_size_t len;
 
-    if (optype == OP_GSOCKOPT)
-	sv = sv_2mortal(NEWSV(22, 257));
-    else
-	sv = POPs;
-    optname = (unsigned int) POPi;
-    lvl = (unsigned int) POPi;
-
-    gv = (GV*)POPs;
-    io = GvIOn(gv);
     if (!io || !IoIFP(io))
 	goto nuts;
 
@@ -2688,12 +2656,12 @@ PP(pp_getpeername)
 {
 #ifdef HAS_SOCKET
     dSP;
-    int optype = PL_op->op_type;
+    const int optype = PL_op->op_type;
+    GV * const gv = (GV*)POPs;
+    register IO * const io = GvIOn(gv);
+    Sock_size_t len;
     SV *sv;
     int fd;
-    GV *gv = (GV*)POPs;
-    register IO *io = GvIOn(gv);
-    Sock_size_t len;
 
     if (!io || !IoIFP(io))
 	goto nuts;
@@ -2784,7 +2752,7 @@ PP(pp_stat)
 	}
     }
     else {
-	SV* sv = POPs;
+	SV* const sv = POPs;
 	if (SvTYPE(sv) == SVt_PVGV) {
 	    gv = (GV*)sv;
 	    goto do_fstat;
@@ -3414,7 +3382,7 @@ PP(pp_chroot)
 {
 #ifdef HAS_CHROOT
     dSP; dTARGET;
-    char *tmps = POPpx;
+    char * const tmps = POPpx;
     TAINT_PROPER("chroot");
     PUSHi( chroot(tmps) >= 0 );
     RETURN;
@@ -3427,8 +3395,8 @@ PP(pp_rename)
 {
     dSP; dTARGET;
     int anum;
-    const char *tmps2 = POPpconstx;
-    const char *tmps = SvPV_nolen_const(TOPs);
+    const char * const tmps2 = POPpconstx;
+    const char * const tmps = SvPV_nolen_const(TOPs);
     TAINT_PROPER("rename");
 #ifdef HAS_RENAME
     anum = PerlLIO_rename(tmps, tmps2);
@@ -3465,8 +3433,8 @@ PP(pp_link)
 #  endif
 
     {
-	const char *tmps2 = POPpconstx;
-	const char *tmps = SvPV_nolen_const(TOPs);
+	const char * const tmps2 = POPpconstx;
+	const char * const tmps = SvPV_nolen_const(TOPs);
 	TAINT_PROPER(PL_op_desc[op_type]);
 	result =
 #  if defined(HAS_LINK)
@@ -3632,18 +3600,13 @@ S_dooneliner(pTHX_ const char *cmd, const char *filename)
 PP(pp_mkdir)
 {
     dSP; dTARGET;
-    int mode;
 #ifndef HAS_MKDIR
     int oldumask;
 #endif
     STRLEN len;
     const char *tmps;
     bool copy = FALSE;
-
-    if (MAXARG > 1)
-	mode = POPi;
-    else
-	mode = 0777;
+    const int mode = (MAXARG > 1) ? POPi : 0777;
 
     TRIMSLASHES(tmps,len,copy);
 
@@ -3686,9 +3649,9 @@ PP(pp_open_dir)
 {
 #if defined(Direntry_t) && defined(HAS_READDIR)
     dSP;
-    const char *dirname = POPpconstx;
-    GV *gv = (GV*)POPs;
-    register IO *io = GvIOn(gv);
+    const char * const dirname = POPpconstx;
+    GV * const gv = (GV*)POPs;
+    register IO * const io = GvIOn(gv);
 
     if (!io)
 	goto nope;
@@ -3720,9 +3683,9 @@ PP(pp_readdir)
 
     SV *sv;
     const I32 gimme = GIMME;
-    GV *gv = (GV *)POPs;
-    register Direntry_t *dp;
-    register IO *io = GvIOn(gv);
+    GV * const gv = (GV *)POPs;
+    register const Direntry_t *dp;
+    register IO * const io = GvIOn(gv);
 
     if (!io || !IoDIRP(io))
 	goto nope;
@@ -3770,8 +3733,8 @@ PP(pp_telldir)
 # if !defined(HAS_TELLDIR_PROTO) || defined(NEED_TELLDIR_PROTO)
     long telldir (DIR *);
 # endif
-    GV *gv = (GV*)POPs;
-    register IO *io = GvIOn(gv);
+    GV * const gv = (GV*)POPs;
+    register IO * const io = GvIOn(gv);
 
     if (!io || !IoDIRP(io))
 	goto nope;
@@ -3791,9 +3754,9 @@ PP(pp_seekdir)
 {
 #if defined(HAS_SEEKDIR) || defined(seekdir)
     dSP;
-    long along = POPl;
-    GV *gv = (GV*)POPs;
-    register IO *io = GvIOn(gv);
+    const long along = POPl;
+    GV * const gv = (GV*)POPs;
+    register IO * const io = GvIOn(gv);
 
     if (!io || !IoDIRP(io))
 	goto nope;
@@ -3814,8 +3777,8 @@ PP(pp_rewinddir)
 {
 #if defined(HAS_REWINDDIR) || defined(rewinddir)
     dSP;
-    GV *gv = (GV*)POPs;
-    register IO *io = GvIOn(gv);
+    GV * const gv = (GV*)POPs;
+    register IO * const io = GvIOn(gv);
 
     if (!io || !IoDIRP(io))
 	goto nope;
@@ -3835,8 +3798,8 @@ PP(pp_closedir)
 {
 #if defined(Direntry_t) && defined(HAS_READDIR)
     dSP;
-    GV *gv = (GV*)POPs;
-    register IO *io = GvIOn(gv);
+    GV * const gv = (GV*)POPs;
+    register IO * const io = GvIOn(gv);
 
     if (!io || !IoDIRP(io))
 	goto nope;
@@ -3868,7 +3831,6 @@ PP(pp_fork)
 #ifdef HAS_FORK
     dSP; dTARGET;
     Pid_t childpid;
-    GV *tmpgv;
 
     EXTEND(SP, 1);
     PERL_FLUSHALL_FOR_CHILD;
@@ -3876,7 +3838,8 @@ PP(pp_fork)
     if (childpid < 0)
 	RETSETUNDEF;
     if (!childpid) {
-	if ((tmpgv = gv_fetchpv("$", TRUE, SVt_PV))) {
+	GV * const tmpgv = gv_fetchpv("$", TRUE, SVt_PV);
+	if (tmpgv) {
             SvREADONLY_off(GvSV(tmpgv));
 	    sv_setiv(GvSV(tmpgv), (IV)PerlProc_getpid());
             SvREADONLY_on(GvSV(tmpgv));
diff --git a/proto.h b/proto.h
index 0c37c5adff..33e9f82b29 100644
--- a/proto.h
+++ b/proto.h
@@ -3762,6 +3762,12 @@ STATIC NV	S_mulexp10(NV value, I32 exponent);
 STATIC STRLEN	S_is_utf8_char_slow(pTHX_ const U8 *s, const STRLEN len)
 			__attribute__nonnull__(pTHX_1);
 
+STATIC bool	S_is_utf8_common(pTHX_ const U8 *const p, SV **swash, const char * const swashname)
+			__attribute__warn_unused_result__
+			__attribute__nonnull__(pTHX_1)
+			__attribute__nonnull__(pTHX_2)
+			__attribute__nonnull__(pTHX_3);
+
 #endif
 
 START_EXTERN_C
diff --git a/scope.c b/scope.c
index 5ef74ecc3d..bc985b72dc 100644
--- a/scope.c
+++ b/scope.c
@@ -169,7 +169,7 @@ S_save_scalar_at(pTHX_ SV **sptr)
 SV *
 Perl_save_scalar(pTHX_ GV *gv)
 {
-    SV **sptr = &GvSV(gv);
+    SV ** const sptr = &GvSV(gv);
     PL_localizing = 1;
     SvGETMAGIC(*sptr);
     PL_localizing = 0;
@@ -963,8 +963,8 @@ Perl_leave_scope(pTHX_ I32 base)
 	case SAVEt_SAVESWITCHSTACK:
 	    {
 		dSP;
-		AV* t = (AV*)SSPOPPTR;
-		AV* f = (AV*)SSPOPPTR;
+		AV* const t = (AV*)SSPOPPTR;
+		AV* const f = (AV*)SSPOPPTR;
 		SWITCHSTACK(t,f);
 		PL_curstackinfo->si_stack = f;
 	    }
diff --git a/universal.c b/universal.c
index f8fa9cda88..1f63563da6 100644
--- a/universal.c
+++ b/universal.c
@@ -66,7 +66,7 @@ S_isa_lookup(pTHX_ HV *stash, const char *name, HV* name_stash,
     {
 	if (SvIV(subgen) == (IV)PL_sub_generation) {
 	    SV* sv;
-	    SV** svp = (SV**)hv_fetch(hv, name, len, FALSE);
+	    SV** const svp = (SV**)hv_fetch(hv, name, len, FALSE);
 	    if (svp && (sv = *svp) != (SV*)&PL_sv_undef) {
 	        DEBUG_o( Perl_deb(aTHX_ "Using cached ISA %s for package %s\n",
 				  name, hvname) );
@@ -435,7 +435,7 @@ XS(XS_version_stringify)
 	  Perl_croak(aTHX_ "Usage: version::stringify(lobj, ...)");
      SP -= items;
      {
-	  SV *	lobj = Nullsv;
+	  SV *	lobj;
 
 	  if (sv_derived_from(ST(0), "version")) {
 	       lobj = SvRV(ST(0));
@@ -457,7 +457,7 @@ XS(XS_version_numify)
 	  Perl_croak(aTHX_ "Usage: version::numify(lobj, ...)");
      SP -= items;
      {
-	  SV *	lobj = Nullsv;
+	  SV *	lobj;
 
 	  if (sv_derived_from(ST(0), "version")) {
 	       lobj = SvRV(ST(0));
@@ -479,7 +479,7 @@ XS(XS_version_normal)
 	  Perl_croak(aTHX_ "Usage: version::normal(lobj, ...)");
      SP -= items;
      {
-	  SV *	lobj = Nullsv;
+	  SV *	lobj;
 
 	  if (sv_derived_from(ST(0), "version")) {
 	       lobj = SvRV(ST(0));
@@ -501,7 +501,7 @@ XS(XS_version_vcmp)
 	  Perl_croak(aTHX_ "Usage: version::vcmp(lobj, ...)");
      SP -= items;
      {
-	  SV *	lobj = Nullsv;
+	  SV *	lobj;
 
 	  if (sv_derived_from(ST(0), "version")) {
 	       lobj = SvRV(ST(0));
@@ -513,7 +513,7 @@ XS(XS_version_vcmp)
 	       SV	*rs;
 	       SV	*rvs;
 	       SV * robj = ST(1);
-	       IV	 swap = (IV)SvIV(ST(2));
+	       const IV	 swap = (IV)SvIV(ST(2));
 
 	       if ( ! sv_derived_from(robj, "version") )
 	       {
diff --git a/utf8.c b/utf8.c
index 84d5553524..88855bb7a6 100644
--- a/utf8.c
+++ b/utf8.c
@@ -1236,7 +1236,7 @@ Perl_to_uni_lower_lc(pTHX_ U32 c)
     return (U32)to_uni_lower(c, tmpbuf, &len);
 }
 
-bool
+static bool
 S_is_utf8_common(pTHX_ const U8 *const p, SV **swash,
 		 const char *const swashname)
 {
diff --git a/util.c b/util.c
index fad5520bea..b558f7a121 100644
--- a/util.c
+++ b/util.c
@@ -291,7 +291,7 @@ char *
 Perl_ninstr(pTHX_ register const char *big, register const char *bigend, const char *little, const char *lend)
 {
     register const I32 first = *little;
-    register const char *littleend = lend;
+    register const char * const littleend = lend;
 
     if (!first && little >= littleend)
 	return (char*)big;
@@ -321,7 +321,7 @@ Perl_rninstr(pTHX_ register const char *big, const char *bigend, const char *lit
 {
     register const char *bigbeg;
     register const I32 first = *little;
-    register const char *littleend = lend;
+    register const char * const littleend = lend;
 
     if (!first && little >= littleend)
 	return (char*)bigend;
@@ -839,7 +839,7 @@ char *
 Perl_savesvpv(pTHX_ SV *sv)
 {
     STRLEN len;
-    const char *pv = SvPV_const(sv, len);
+    const char * const pv = SvPV_const(sv, len);
     register char *newaddr;
 
     ++len;
@@ -1358,7 +1358,7 @@ Perl_vwarner(pTHX_ U32  err, const char* pat, va_list* args)
     if (ckDEAD(err)) {
 	SV * const msv = vmess(pat, args);
 	STRLEN msglen;
-	const char *message = SvPV_const(msv, msglen);
+	const char * const message = SvPV_const(msv, msglen);
 	const I32 utf8 = SvUTF8(msv);
 
 	if (PL_diehook) {
@@ -2739,7 +2739,7 @@ Perl_my_pclose(pTHX_ PerlIO *ptr)
 {
     /* Needs work for PerlIO ! */
     FILE * const f = PerlIO_findFILE(ptr);
-    I32 result = pclose(f);
+    const I32 result = pclose(f);
     PerlIO_releaseFILE(ptr,f);
     return result;
 }
@@ -3147,7 +3147,7 @@ Perl_getenv_len(pTHX_ const char *env_elem, unsigned long *len)
 MGVTBL*
 Perl_get_vtbl(pTHX_ int vtbl_id)
 {
-    const MGVTBL* result = Null(MGVTBL*);
+    const MGVTBL* result;
 
     switch(vtbl_id) {
     case want_vtbl_sv:
@@ -3242,6 +3242,9 @@ Perl_get_vtbl(pTHX_ int vtbl_id)
     case want_vtbl_utf8:
 	result = &PL_vtbl_utf8;
 	break;
+    default:
+	result = Null(MGVTBL*);
+	break;
     }
     return (MGVTBL*)result;
 }
@@ -3916,8 +3919,8 @@ Perl_scan_version(pTHX_ const char *s, SV *rv, bool qv)
     int saw_period = 0;
     int alpha = 0;
     int width = 3;
-    AV *av = newAV();
-    SV *hv = newSVrv(rv, "version"); /* create an SV and upgrade the RV */
+    AV * const av = newAV();
+    SV * const hv = newSVrv(rv, "version"); /* create an SV and upgrade the RV */
     (void)sv_upgrade(hv, SVt_PVHV); /* needs to be an HV type */
 
 #ifndef NODEFAULT_SHAREKEYS
@@ -4705,7 +4708,7 @@ Perl_my_socketpair (int family, int type, int protocol, int fd[2]) {
 #endif
   tidy_up_and_fail:
     {
-	int save_errno = errno;
+	const int save_errno = errno;
 	if (listener != -1)
 	    PerlLIO_close(listener);
 	if (connector != -1)
@@ -4945,8 +4948,8 @@ Perl_init_global_struct(pTHX)
 #ifdef PERL_GLOBAL_STRUCT
 #  define PERL_GLOBAL_STRUCT_INIT
 #  include "opcode.h" /* the ppaddr and check */
-    IV nppaddr = sizeof(Gppaddr)/sizeof(Perl_ppaddr_t);
-    IV ncheck  = sizeof(Gcheck) /sizeof(Perl_check_t);
+    const IV nppaddr = sizeof(Gppaddr)/sizeof(Perl_ppaddr_t);
+    const IV ncheck  = sizeof(Gcheck) /sizeof(Perl_check_t);
 #  ifdef PERL_GLOBAL_STRUCT_PRIVATE
     /* PerlMem_malloc() because can't use even safesysmalloc() this early. */
     plvarsp = (struct perl_vars*)PerlMem_malloc(sizeof(struct perl_vars));