Silence some warnings on Win32 with VC6

VC7 onwards didn't seem to mind (perhaps thanks to #33411):
http://www.nntp.perl.org/group/perl.daily-build.reports/2008/03/msg54118.html
but VC6 wasn't happy:
http://www.nntp.perl.org/group/perl.daily-build.reports/2008/03/msg54099.html

p4raw-id: //depot/perl@33448

4 files changed, 31 insertions, 31 deletions

diff --git a/embed.fnc b/embed.fnc
index 6c727bf69d..42991adc68 100644
--- a/embed.fnc
+++ b/embed.fnc
@@ -1379,15 +1379,15 @@ sR	|SV*	|method_common	|NN SV* meth|NULLOK U32* hashp
 #endif
 
 #if defined(PERL_IN_PP_SORT_C) || defined(PERL_DECL_PROT)
-s	|I32	|sv_ncmp	|NN SV *a|NN SV *b
-s	|I32	|sv_i_ncmp	|NN SV *a|NN SV *b
-s	|I32	|amagic_ncmp	|NN SV *a|NN SV *b
-s	|I32	|amagic_i_ncmp	|NN SV *a|NN SV *b
-s	|I32	|amagic_cmp	|NN SV *str1|NN SV *str2
-s	|I32	|amagic_cmp_locale|NN SV *str1|NN SV *str2
-s	|I32	|sortcv		|NN SV *a|NN SV *b
-s	|I32	|sortcv_xsub	|NN SV *a|NN SV *b
-s	|I32	|sortcv_stacked	|NN SV *a|NN SV *b
+s	|I32	|sv_ncmp	|NN SV *const a|NN SV *const b
+s	|I32	|sv_i_ncmp	|NN SV *const a|NN SV *const b
+s	|I32	|amagic_ncmp	|NN SV *const a|NN SV *const b
+s	|I32	|amagic_i_ncmp	|NN SV *const a|NN SV *const b
+s	|I32	|amagic_cmp	|NN SV *const str1|NN SV *const str2
+s	|I32	|amagic_cmp_locale|NN SV *const str1|NN SV *const str2
+s	|I32	|sortcv		|NN SV *const a|NN SV *const b
+s	|I32	|sortcv_xsub	|NN SV *const a|NN SV *const b
+s	|I32	|sortcv_stacked	|NN SV *const a|NN SV *const b
 s	|void	|qsortsvu	|NULLOK SV** array|size_t num_elts|NN SVCOMPARE_t compare
 #endif
 
diff --git a/perl.h b/perl.h
index 65b3a722bc..87ad969f54 100644
--- a/perl.h
+++ b/perl.h
@@ -4649,7 +4649,7 @@ typedef regexp*(CPERLscope(*regdupe_t)) (pTHX_ const regexp* r, CLONE_PARAMS *pa
 typedef void (*DESTRUCTORFUNC_NOCONTEXT_t) (void*);
 typedef void (*DESTRUCTORFUNC_t) (pTHX_ void*);
 typedef void (*SVFUNC_t) (pTHX_ SV* const);
-typedef I32  (*SVCOMPARE_t) (pTHX_ SV*, SV*);
+typedef I32  (*SVCOMPARE_t) (pTHX_ SV* const, SV* const);
 typedef void (*XSINIT_t) (pTHX);
 typedef void (*ATEXIT_t) (pTHX_ void*);
 typedef void (*XSUBADDR_t) (pTHX_ CV *);
diff --git a/pp_sort.c b/pp_sort.c
index 1c120148c5..9fe0dadae7 100644
--- a/pp_sort.c
+++ b/pp_sort.c
@@ -340,7 +340,7 @@ typedef struct {
 
 
 static I32
-cmp_desc(pTHX_ gptr a, gptr b)
+cmp_desc(pTHX_ gptr const a, gptr const b)
 {
     dVAR;
     return -PL_sort_RealCmp(aTHX_ a, b);
@@ -1315,7 +1315,7 @@ S_qsortsvu(pTHX_ SV ** array, size_t num_elts, SVCOMPARE_t compare)
 
 
 static I32
-cmpindir(pTHX_ gptr a, gptr b)
+cmpindir(pTHX_ gptr const a, gptr const b)
 {
     dVAR;
     gptr * const ap = (gptr *)a;
@@ -1328,7 +1328,7 @@ cmpindir(pTHX_ gptr a, gptr b)
 }
 
 static I32
-cmpindir_desc(pTHX_ gptr a, gptr b)
+cmpindir_desc(pTHX_ gptr const a, gptr const b)
 {
     dVAR;
     gptr * const ap = (gptr *)a;
@@ -1738,7 +1738,7 @@ PP(pp_sort)
 }
 
 static I32
-S_sortcv(pTHX_ SV *a, SV *b)
+S_sortcv(pTHX_ SV *const a, SV *const b)
 {
     dVAR;
     const I32 oldsaveix = PL_savestack_ix;
@@ -1765,7 +1765,7 @@ S_sortcv(pTHX_ SV *a, SV *b)
 }
 
 static I32
-S_sortcv_stacked(pTHX_ SV *a, SV *b)
+S_sortcv_stacked(pTHX_ SV *const a, SV *const b)
 {
     dVAR;
     const I32 oldsaveix = PL_savestack_ix;
@@ -1807,7 +1807,7 @@ S_sortcv_stacked(pTHX_ SV *a, SV *b)
 }
 
 static I32
-S_sortcv_xsub(pTHX_ SV *a, SV *b)
+S_sortcv_xsub(pTHX_ SV *const a, SV *const b)
 {
     dVAR; dSP;
     const I32 oldsaveix = PL_savestack_ix;
@@ -1838,7 +1838,7 @@ S_sortcv_xsub(pTHX_ SV *a, SV *b)
 
 
 static I32
-S_sv_ncmp(pTHX_ SV *a, SV *b)
+S_sv_ncmp(pTHX_ SV *const a, SV *const b)
 {
     const NV nv1 = SvNSIV(a);
     const NV nv2 = SvNSIV(b);
@@ -1849,7 +1849,7 @@ S_sv_ncmp(pTHX_ SV *a, SV *b)
 }
 
 static I32
-S_sv_i_ncmp(pTHX_ SV *a, SV *b)
+S_sv_i_ncmp(pTHX_ SV *const a, SV *const b)
 {
     const IV iv1 = SvIV(a);
     const IV iv2 = SvIV(b);
@@ -1867,7 +1867,7 @@ S_sv_i_ncmp(pTHX_ SV *a, SV *b)
 #define SORT_NORMAL_RETURN_VALUE(val)  (((val) > 0) ? 1 : ((val) ? -1 : 0))
 
 static I32
-S_amagic_ncmp(pTHX_ register SV *a, register SV *b)
+S_amagic_ncmp(pTHX_ register SV *const a, register SV *const b)
 {
     dVAR;
     SV * const tmpsv = tryCALL_AMAGICbin(a,b,ncmp);
@@ -1888,7 +1888,7 @@ S_amagic_ncmp(pTHX_ register SV *a, register SV *b)
 }
 
 static I32
-S_amagic_i_ncmp(pTHX_ register SV *a, register SV *b)
+S_amagic_i_ncmp(pTHX_ register SV *const a, register SV *const b)
 {
     dVAR;
     SV * const tmpsv = tryCALL_AMAGICbin(a,b,ncmp);
@@ -1909,7 +1909,7 @@ S_amagic_i_ncmp(pTHX_ register SV *a, register SV *b)
 }
 
 static I32
-S_amagic_cmp(pTHX_ register SV *str1, register SV *str2)
+S_amagic_cmp(pTHX_ register SV *const str1, register SV *const str2)
 {
     dVAR;
     SV * const tmpsv = tryCALL_AMAGICbin(str1,str2,scmp);
@@ -1930,7 +1930,7 @@ S_amagic_cmp(pTHX_ register SV *str1, register SV *str2)
 }
 
 static I32
-S_amagic_cmp_locale(pTHX_ register SV *str1, register SV *str2)
+S_amagic_cmp_locale(pTHX_ register SV *const str1, register SV *const str2)
 {
     dVAR;
     SV * const tmpsv = tryCALL_AMAGICbin(str1,str2,scmp);
diff --git a/proto.h b/proto.h
index 410b60a511..474bec9564 100644
--- a/proto.h
+++ b/proto.h
@@ -5011,55 +5011,55 @@ STATIC SV*	S_method_common(pTHX_ SV* meth, U32* hashp)
 #endif
 
 #if defined(PERL_IN_PP_SORT_C) || defined(PERL_DECL_PROT)
-STATIC I32	S_sv_ncmp(pTHX_ SV *a, SV *b)
+STATIC I32	S_sv_ncmp(pTHX_ SV *const a, SV *const b)
 			__attribute__nonnull__(pTHX_1)
 			__attribute__nonnull__(pTHX_2);
 #define PERL_ARGS_ASSERT_SV_NCMP	\
 	assert(a); assert(b)
 
-STATIC I32	S_sv_i_ncmp(pTHX_ SV *a, SV *b)
+STATIC I32	S_sv_i_ncmp(pTHX_ SV *const a, SV *const b)
 			__attribute__nonnull__(pTHX_1)
 			__attribute__nonnull__(pTHX_2);
 #define PERL_ARGS_ASSERT_SV_I_NCMP	\
 	assert(a); assert(b)
 
-STATIC I32	S_amagic_ncmp(pTHX_ SV *a, SV *b)
+STATIC I32	S_amagic_ncmp(pTHX_ SV *const a, SV *const b)
 			__attribute__nonnull__(pTHX_1)
 			__attribute__nonnull__(pTHX_2);
 #define PERL_ARGS_ASSERT_AMAGIC_NCMP	\
 	assert(a); assert(b)
 
-STATIC I32	S_amagic_i_ncmp(pTHX_ SV *a, SV *b)
+STATIC I32	S_amagic_i_ncmp(pTHX_ SV *const a, SV *const b)
 			__attribute__nonnull__(pTHX_1)
 			__attribute__nonnull__(pTHX_2);
 #define PERL_ARGS_ASSERT_AMAGIC_I_NCMP	\
 	assert(a); assert(b)
 
-STATIC I32	S_amagic_cmp(pTHX_ SV *str1, SV *str2)
+STATIC I32	S_amagic_cmp(pTHX_ SV *const str1, SV *const str2)
 			__attribute__nonnull__(pTHX_1)
 			__attribute__nonnull__(pTHX_2);
 #define PERL_ARGS_ASSERT_AMAGIC_CMP	\
 	assert(str1); assert(str2)
 
-STATIC I32	S_amagic_cmp_locale(pTHX_ SV *str1, SV *str2)
+STATIC I32	S_amagic_cmp_locale(pTHX_ SV *const str1, SV *const str2)
 			__attribute__nonnull__(pTHX_1)
 			__attribute__nonnull__(pTHX_2);
 #define PERL_ARGS_ASSERT_AMAGIC_CMP_LOCALE	\
 	assert(str1); assert(str2)
 
-STATIC I32	S_sortcv(pTHX_ SV *a, SV *b)
+STATIC I32	S_sortcv(pTHX_ SV *const a, SV *const b)
 			__attribute__nonnull__(pTHX_1)
 			__attribute__nonnull__(pTHX_2);
 #define PERL_ARGS_ASSERT_SORTCV	\
 	assert(a); assert(b)
 
-STATIC I32	S_sortcv_xsub(pTHX_ SV *a, SV *b)
+STATIC I32	S_sortcv_xsub(pTHX_ SV *const a, SV *const b)
 			__attribute__nonnull__(pTHX_1)
 			__attribute__nonnull__(pTHX_2);
 #define PERL_ARGS_ASSERT_SORTCV_XSUB	\
 	assert(a); assert(b)
 
-STATIC I32	S_sortcv_stacked(pTHX_ SV *a, SV *b)
+STATIC I32	S_sortcv_stacked(pTHX_ SV *const a, SV *const b)
 			__attribute__nonnull__(pTHX_1)
 			__attribute__nonnull__(pTHX_2);
 #define PERL_ARGS_ASSERT_SORTCV_STACKED	\