Moving variables to their innermost scope.

Some vars have been tagged as const because they do not change in their
new scopes. In pp_reverse in pp.c, I32 tmp is only used to hold a char,
so is changed to char.

10 files changed, 38 insertions, 35 deletions

diff --git a/doop.c b/doop.c
index e4b2cd825c..b5c10039b6 100644
--- a/doop.c
+++ b/doop.c
@@ -1065,16 +1065,16 @@ Perl_do_vop(pTHX_ I32 optype, SV *sv, SV *left, SV *right)
 	dc = SvPVX(sv);		/* sv_usepvn() calls Renew() */
     }
     if (left_utf || right_utf) {
-	UV duc, luc, ruc;
 	char *dcorig = dc;
 	char *dcsave = NULL;
 	STRLEN lulen = leftlen;
 	STRLEN rulen = rightlen;
-	STRLEN ulen;
 
 	switch (optype) {
 	case OP_BIT_AND:
 	    while (lulen && rulen) {
+                UV duc, luc, ruc;
+                STRLEN ulen;
 		luc = utf8n_to_uvchr((U8*)lc, lulen, &ulen, UTF8_ALLOW_ANYUV);
 		lc += ulen;
 		lulen -= ulen;
@@ -1097,6 +1097,8 @@ Perl_do_vop(pTHX_ I32 optype, SV *sv, SV *left, SV *right)
 	    break;
 	case OP_BIT_XOR:
 	    while (lulen && rulen) {
+                UV duc, luc, ruc;
+                STRLEN ulen;
 		luc = utf8n_to_uvchr((U8*)lc, lulen, &ulen, UTF8_ALLOW_ANYUV);
 		lc += ulen;
 		lulen -= ulen;
@@ -1114,6 +1116,8 @@ Perl_do_vop(pTHX_ I32 optype, SV *sv, SV *left, SV *right)
 	    goto mop_up_utf;
 	case OP_BIT_OR:
 	    while (lulen && rulen) {
+                UV duc, luc, ruc;
+                STRLEN ulen;
 		luc = utf8n_to_uvchr((U8*)lc, lulen, &ulen, UTF8_ALLOW_ANYUV);
 		lc += ulen;
 		lulen -= ulen;
diff --git a/mg.c b/mg.c
index 6e648d8c2e..b11f66acb0 100644
--- a/mg.c
+++ b/mg.c
@@ -607,9 +607,9 @@ Perl_mg_free_type(pTHX_ SV *sv, int how)
     MAGIC *mg, *prevmg, *moremg;
     PERL_ARGS_ASSERT_MG_FREE_TYPE;
     for (prevmg = NULL, mg = SvMAGIC(sv); mg; prevmg = mg, mg = moremg) {
-	MAGIC *newhead;
 	moremg = mg->mg_moremagic;
 	if (mg->mg_type == how) {
+            MAGIC *newhead;
 	    /* temporarily move to the head of the magic chain, in case
 	       custom free code relies on this historical aspect of mg_free */
 	    if (prevmg) {
@@ -1138,9 +1138,9 @@ Perl_magic_get(pTHX_ SV *sv, MAGIC *mg)
 #ifdef HAS_GETGROUPS
 	{
 	    Groups_t *gary = NULL;
-	    I32 i;
             I32 num_groups = getgroups(0, gary);
             if (num_groups > 0) {
+                I32 i;
                 Newx(gary, num_groups, Groups_t);
                 num_groups = getgroups(num_groups, gary);
                 for (i = 0; i < num_groups; i++)
@@ -2149,7 +2149,6 @@ Perl_magic_setpos(pTHX_ SV *sv, MAGIC *mg)
     SV* const lsv = LvTARG(sv);
     SSize_t pos;
     STRLEN len;
-    STRLEN ulen = 0;
     MAGIC* found;
     const char *s;
 
@@ -2171,7 +2170,7 @@ Perl_magic_setpos(pTHX_ SV *sv, MAGIC *mg)
     pos = SvIV(sv);
 
     if (DO_UTF8(lsv)) {
-	ulen = sv_or_pv_len_utf8(lsv, s, len);
+        const STRLEN ulen = sv_or_pv_len_utf8(lsv, s, len);
 	if (ulen)
 	    len = ulen;
     }
diff --git a/op.c b/op.c
index 66c4a9b1b4..dca52e2b44 100644
--- a/op.c
+++ b/op.c
@@ -487,13 +487,13 @@ void
 Perl_opslab_force_free(pTHX_ OPSLAB *slab)
 {
     OPSLAB *slab2;
-    OPSLOT *slot;
 #ifdef DEBUGGING
     size_t savestack_count = 0;
 #endif
     PERL_ARGS_ASSERT_OPSLAB_FORCE_FREE;
     slab2 = slab;
     do {
+        OPSLOT *slot;
 	for (slot = slab2->opslab_first;
 	     slot->opslot_next;
 	     slot = slot->opslot_next) {
@@ -1865,7 +1865,6 @@ Perl_scalarvoid(pTHX_ OP *arg)
     dVAR;
     OP *kid;
     SV* sv;
-    U8 want;
     SSize_t defer_stack_alloc = 0;
     SSize_t defer_ix = -1;
     OP **defer_stack = NULL;
@@ -1874,6 +1873,7 @@ Perl_scalarvoid(pTHX_ OP *arg)
     PERL_ARGS_ASSERT_SCALARVOID;
 
     do {
+        U8 want;
         SV *useless_sv = NULL;
         const char* useless = NULL;
 
@@ -10895,7 +10895,6 @@ Perl_ck_require(pTHX_ OP *o)
 
     if (o->op_flags & OPf_KIDS) {	/* Shall we supply missing .pm? */
 	SVOP * const kid = (SVOP*)cUNOPo->op_first;
-	HEK *hek;
 	U32 hash;
 	char *s;
 	STRLEN len;
@@ -10905,6 +10904,7 @@ Perl_ck_require(pTHX_ OP *o)
 	  if (kid->op_private & OPpCONST_BARE) {
             dVAR;
 	    const char *end;
+            HEK *hek;
 
 	    if (was_readonly) {
 		    SvREADONLY_off(sv);
@@ -10947,6 +10947,7 @@ Perl_ck_require(pTHX_ OP *o)
 	    }
 	    else {
                 dVAR;
+                HEK *hek;
 		if (was_readonly) SvREADONLY_off(sv);
 		PERL_HASH(hash, s, len);
 		hek = share_hek(s,
diff --git a/perl.c b/perl.c
index 98bf356652..658f260997 100644
--- a/perl.c
+++ b/perl.c
@@ -1580,7 +1580,6 @@ perl_parse(pTHXx_ XSINIT_t xsinit, int argc, char **argv, char **env)
 	 * the original argv[0].  (See below for 'contiguous', though.)
 	 * --jhi */
 	 const char *s = NULL;
-	 int i;
 	 const UV mask = ~(UV)(PTRSIZE-1);
          /* Do the mask check only if the args seem like aligned. */
 	 const UV aligned =
@@ -1596,6 +1595,7 @@ perl_parse(pTHXx_ XSINIT_t xsinit, int argc, char **argv, char **env)
 	  * like the argv[] interleaved with some other data, we are
 	  * fine.  (Did I just evoke Murphy's Law?)  --jhi */
 	 if (PL_origargv && PL_origargc >= 1 && (s = PL_origargv[0])) {
+              int i;
 	      while (*s) s++;
 	      for (i = 1; i < PL_origargc; i++) {
 		   if ((PL_origargv[i] == s + 1
@@ -1629,6 +1629,7 @@ perl_parse(pTHXx_ XSINIT_t xsinit, int argc, char **argv, char **env)
 		    INT2PTR(char *, PTR2UV(s + PTRSIZE) & mask)))
 		 )
 	      {
+                   int i;
 #ifndef OS2		/* ENVIRON is read by the kernel too. */
 		   s = PL_origenviron[0];
 		   while (*s) s++;
diff --git a/pp.c b/pp.c
index 3e6b891f25..4bd5f0fb68 100644
--- a/pp.c
+++ b/pp.c
@@ -5652,8 +5652,6 @@ PP(pp_reverse)
     }
     else {
 	char *up;
-	char *down;
-	I32 tmp;
 	dTARGET;
 	STRLEN len;
 
@@ -5666,6 +5664,7 @@ PP(pp_reverse)
 
 	up = SvPV_force(TARG, len);
 	if (len > 1) {
+            char *down;
 	    if (DO_UTF8(TARG)) {	/* first reverse each character */
 		U8* s = (U8*)SvPVX(TARG);
 		const U8* send = (U8*)(s + len);
@@ -5682,9 +5681,9 @@ PP(pp_reverse)
 			down = (char*)(s - 1);
 			/* reverse this character */
 			while (down > up) {
-			    tmp = *up;
+                            const char tmp = *up;
 			    *up++ = *down;
-			    *down-- = (char)tmp;
+                            *down-- = tmp;
 			}
 		    }
 		}
@@ -5692,9 +5691,9 @@ PP(pp_reverse)
 	    }
 	    down = SvPVX(TARG) + len - 1;
 	    while (down > up) {
-		tmp = *up;
+                const char tmp = *up;
 		*up++ = *down;
-		*down-- = (char)tmp;
+                *down-- = tmp;
 	    }
 	    (void)SvPOK_only_UTF8(TARG);
 	}
diff --git a/pp_hot.c b/pp_hot.c
index 7d6db0f4f0..58bbe2f1e9 100644
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -360,7 +360,6 @@ PP(pp_padrange)
     dSP;
     PADOFFSET base = PL_op->op_targ;
     int count = (int)(PL_op->op_private) & OPpPADRANGE_COUNTMASK;
-    int i;
     if (PL_op->op_flags & OPf_SPECIAL) {
         /* fake the RHS of my ($x,$y,..) = @_ */
         PUSHMARK(SP);
@@ -370,6 +369,8 @@ PP(pp_padrange)
 
     /* note, this is only skipped for compile-time-known void cxt */
     if ((PL_op->op_flags & OPf_WANT) != OPf_WANT_VOID) {
+        int i;
+
         EXTEND(SP, count);
         PUSHMARK(SP);
         for (i = 0; i <count; i++)
@@ -381,6 +382,8 @@ PP(pp_padrange)
                       (base << (OPpPADRANGE_COUNTSHIFT + SAVE_TIGHT_SHIFT))
                     | (count << SAVE_TIGHT_SHIFT)
                     | SAVEt_CLEARPADRANGE);
+        int i;
+
         STATIC_ASSERT_STMT(OPpPADRANGE_COUNTMASK + 1 == (1 << OPpPADRANGE_COUNTSHIFT));
         assert((payload >> (OPpPADRANGE_COUNTSHIFT+SAVE_TIGHT_SHIFT))
                 == (Size_t)base);
diff --git a/pp_sys.c b/pp_sys.c
index 9874107e06..7a5703515c 100644
--- a/pp_sys.c
+++ b/pp_sys.c
@@ -1432,7 +1432,6 @@ PP(pp_enterwrite)
     IO *io;
     GV *fgv;
     CV *cv = NULL;
-    SV *tmpsv = NULL;
 
     if (MAXARG == 0) {
 	EXTEND(SP, 1);
@@ -1456,7 +1455,7 @@ PP(pp_enterwrite)
 
     cv = GvFORM(fgv);
     if (!cv) {
-	tmpsv = sv_newmortal();
+        SV * const tmpsv = sv_newmortal();
 	gv_efullname4(tmpsv, fgv, NULL, FALSE);
 	DIE(aTHX_ "Undefined format \"%" SVf "\" called", SVfARG(tmpsv));
     }
@@ -4439,10 +4438,9 @@ PP(pp_system)
 	    if (did_pipes) {
 		int errkid;
 		unsigned n = 0;
-		SSize_t n1;
 
 		while (n < sizeof(int)) {
-		    n1 = PerlLIO_read(pp[0],
+                    const SSize_t n1 = PerlLIO_read(pp[0],
 				      (void*)(((char*)&errkid)+n),
 				      (sizeof(int)) - n);
 		    if (n1 <= 0)
@@ -4851,7 +4849,6 @@ PP(pp_alarm)
 PP(pp_sleep)
 {
     dSP; dTARGET;
-    I32 duration;
     Time_t lasttime;
     Time_t when;
 
@@ -4859,7 +4856,7 @@ PP(pp_sleep)
     if (MAXARG < 1 || (!TOPs && !POPs))
 	PerlProc_pause();
     else {
-	duration = POPi;
+        const I32 duration = POPi;
         if (duration < 0) {
           /* diag_listed_as: %s() with negative argument */
           Perl_ck_warner_d(aTHX_ packWARN(WARN_MISC),
diff --git a/taint.c b/taint.c
index f1f6b7b73d..1b78928867 100644
--- a/taint.c
+++ b/taint.c
@@ -78,7 +78,6 @@ void
 Perl_taint_env(pTHX)
 {
     SV** svp;
-    MAGIC* mg;
     const char* const *e;
     static const char* const misc_env[] = {
 	"IFS",		/* most shells' inter-field separators */
@@ -121,6 +120,7 @@ Perl_taint_env(pTHX)
     STRLEN len = 8; /* strlen(name)  */
 
     while (1) {
+        MAGIC* mg;
 	if (i)
 	    len = my_sprintf(name,"DCL$PATH;%d", i);
 	svp = hv_fetch(GvHVn(PL_envgv), name, len, FALSE);
@@ -141,6 +141,7 @@ Perl_taint_env(pTHX)
 
     svp = hv_fetchs(GvHVn(PL_envgv),"PATH",FALSE);
     if (svp && *svp) {
+        MAGIC* mg;
 	if (SvTAINTED(*svp)) {
 	    TAINT;
 	    taint_proper("Insecure %s%s", "$ENV{PATH}");
diff --git a/toke.c b/toke.c
index 6d0ab625c0..5a711d3ca3 100644
--- a/toke.c
+++ b/toke.c
@@ -3275,18 +3275,18 @@ S_scan_const(pTHX_ char *start)
 #endif
                 /* Always gets run for ASCII, and sometimes for EBCDIC. */
                 {
-                    SSize_t i;
-
                     /* Here, no conversions are necessary, which means that the
                      * first character in the range is already in 'd' and
                      * valid, so we can skip overwriting it */
                     if (has_utf8) {
+                        SSize_t i;
                         d += UTF8SKIP(d);
                         for (i = range_min + 1; i <= range_max; i++) {
                             append_utf8_from_native_byte((U8) i, (U8 **) &d);
                         }
                     }
                     else {
+                        SSize_t i;
                         d++;
                         assert(range_min + 1 <= range_max);
                         for (i = range_min + 1; i < range_max; i++) {
@@ -9040,7 +9040,6 @@ S_checkcomma(pTHX_ const char *s, const char *name, const char *what)
 	    s++;
 	if (*s == ',') {
 	    GV* gv;
-	    PADOFFSET off;
 	    if (keyword(w, s - w, 0))
 		return;
 
@@ -9048,6 +9047,7 @@ S_checkcomma(pTHX_ const char *s, const char *name, const char *what)
 	    if (gv && GvCVu(gv))
 		return;
 	    if (s - w <= 254) {
+                PADOFFSET off;
 		char tmpbuf[256];
 		Copy(w, tmpbuf+1, s - w, char);
 		*tmpbuf = '&';
@@ -11335,8 +11335,6 @@ Perl_scan_num(pTHX_ const char *start, YYSTYPE* lvalp)
 STATIC char *
 S_scan_formline(pTHX_ char *s)
 {
-    char *eol;
-    char *t;
     SV * const stuff = newSVpvs("");
     bool needargs = FALSE;
     bool eofmt = FALSE;
@@ -11344,8 +11342,9 @@ S_scan_formline(pTHX_ char *s)
     PERL_ARGS_ASSERT_SCAN_FORMLINE;
 
     while (!needargs) {
+        char *eol;
 	if (*s == '.') {
-	    t = s+1;
+            char *t = s+1;
 #ifdef PERL_STRICT_CR
 	    while (SPACE_OR_TAB(*t))
 		t++;
@@ -11362,6 +11361,7 @@ S_scan_formline(pTHX_ char *s)
 	if (!eol++)
 		eol = PL_bufend;
 	if (*s != '#') {
+            char *t;
 	    for (t = s; t < eol; t++) {
 		if (*t == '~' && t[1] == '~' && SvCUR(stuff)) {
 		    needargs = FALSE;
diff --git a/util.c b/util.c
index f119f3cd3d..406286c219 100644
--- a/util.c
+++ b/util.c
@@ -619,11 +619,11 @@ Perl_ninstr(const char *big, const char *bigend, const char *little, const char
         return (char*)big;
     {
         const char first = *little;
-        const char *s, *x;
         bigend -= lend - little++;
     OUTER:
         while (big <= bigend) {
             if (*big++ == first) {
+                const char *s, *x;
                 for (x=big,s=little; s < lend; x++,s++) {
                     if (*s != *x)
                         goto OUTER;
@@ -2540,10 +2540,9 @@ Perl_my_popen_list(pTHX_ const char *mode, int n, SV **args)
     if (did_pipes && pid > 0) {
 	int errkid;
 	unsigned n = 0;
-	SSize_t n1;
 
 	while (n < sizeof(int)) {
-	    n1 = PerlLIO_read(pp[0],
+            const SSize_t n1 = PerlLIO_read(pp[0],
 			      (void*)(((char*)&errkid)+n),
 			      (sizeof(int)) - n);
 	    if (n1 <= 0)
@@ -2698,10 +2697,9 @@ Perl_my_popen(pTHX_ const char *cmd, const char *mode)
     if (did_pipes && pid > 0) {
 	int errkid;
 	unsigned n = 0;
-	SSize_t n1;
 
 	while (n < sizeof(int)) {
-	    n1 = PerlLIO_read(pp[0],
+            const SSize_t n1 = PerlLIO_read(pp[0],
 			      (void*)(((char*)&errkid)+n),
 			      (sizeof(int)) - n);
 	    if (n1 <= 0)