Fix bug id 20020427.004 on %^H.

Add a regression test for %^H.
Change the sort pragma implementation to use a
global variable instead of %^H.

p4raw-id: //depot/perl@16286

MANIFEST

@@ -2291,6 +2291,7 @@ t/comp/colon.t			See if colons are parsed correctly
 t/comp/cpp.aux			main file for cpp.t
 t/comp/cpp.t			See if C preprocessor works
 t/comp/decl.t			See if declarations work
+t/comp/hints.t			See if %^H works
 t/comp/multiline.t		See if multiline strings work
 t/comp/package.t		See if packages work
 t/comp/proto.t			See if function prototypes work

lib/sort.pm

@@ -1,8 +1,13 @@
 package sort;
 
-our $VERSION = '1.00';
+our $VERSION = '1.01';
 
-$sort::hint_bits       = 0x00020000; # HINT_LOCALIZE_HH, really...
+# Currently the hints for pp_sort are stored in the global variable
+# $sort::hints. An improvement would be to store them in $^H{SORT} and have
+# this information available somewhere in the listop OP_SORT, to allow lexical
+# scoping of this pragma. -- rgs 2002-04-30
+
+our $hints	       = 0;
 
 $sort::quicksort_bit   = 0x00000001;
 $sort::mergesort_bit   = 0x00000002;
@@ -17,18 +22,17 @@ sub import {
 	require Carp;
 	Carp::croak("sort pragma requires arguments");
     }
-    $^H |= $sort::hint_bits;
     local $_;
-    no warnings 'uninitialized';	# $^H{SORT} bitops would warn
+    no warnings 'uninitialized';	# bitops would warn
     while ($_ = shift(@_)) {
 	if (/^_q(?:uick)?sort$/) {
-	    $^H{SORT} &= ~$sort::sort_bits;
-	    $^H{SORT} |=  $sort::quicksort_bit;
+	    $hints &= ~$sort::sort_bits;
+	    $hints |=  $sort::quicksort_bit;
 	} elsif ($_ eq '_mergesort') {
-	    $^H{SORT} &= ~$sort::sort_bits;
-	    $^H{SORT} |=  $sort::mergesort_bit;
+	    $hints &= ~$sort::sort_bits;
+	    $hints |=  $sort::mergesort_bit;
 	} elsif ($_ eq 'stable') {
-	    $^H{SORT} |=  $sort::stable_bit;
+	    $hints |=  $sort::stable_bit;
 	} else {
 	    require Carp;
 	    Carp::croak("sort: unknown subpragma '$_'");
@@ -38,10 +42,10 @@ sub import {
 
 sub current {
     my @sort;
-    if ($^H{SORT}) {
-	push @sort, 'quicksort' if $^H{SORT} & $sort::quicksort_bit;
-	push @sort, 'mergesort' if $^H{SORT} & $sort::mergesort_bit;
-	push @sort, 'stable'    if $^H{SORT} & $sort::stable_bit;
+    if ($hints) {
+	push @sort, 'quicksort' if $hints & $sort::quicksort_bit;
+	push @sort, 'mergesort' if $hints & $sort::mergesort_bit;
+	push @sort, 'stable'    if $hints & $sort::stable_bit;
     }
     push @sort, 'mergesort' unless @sort;
     join(' ', @sort);

lib/sort.t

@@ -136,9 +136,8 @@ main(0);
 
 # XXX We're using this eval "..." trick to force recompilation,
 # to ensure that the correct pragma is enabled when main() is run.
-# Currently 'use sort' modifies $^H{SORT} at compile-time, but
-# pp_sort() fetches its value at run-time : thus the lexical scoping
-# of %^H is of no utility.
+# Currently 'use sort' modifies $sort::hints at compile-time, but
+# pp_sort() fetches its value at run-time.
 # The order of those evals is important.
 
 eval q{

pp_sort.c

@@ -34,10 +34,9 @@ static I32 amagic_cmp_locale(pTHX_ SV *a, SV *b);
 #define sv_cmp_static Perl_sv_cmp
 #define sv_cmp_locale_static Perl_sv_cmp_locale
 
-#define SORTHINTS(hintsvp) \
-     ((PL_hintgv &&	\
-      (hintsvp = hv_fetch(GvHV(PL_hintgv), "SORT", 4, FALSE))) ? \
-	  (I32)SvIV(*hintsvp) : 0)
+#define SORTHINTS(hintsv) \
+    (((hintsv) = GvSV(gv_fetchpv("sort::hints", GV_ADDMULTI, SVt_IV))), \
+    (SvIOK(hintsv) ? ((I32)SvIV(hintsv)) : 0))
 
 #ifndef SMALLSORT
 #define	SMALLSORT (200)
@@ -1304,9 +1303,9 @@ cmpindir(pTHX_ gptr a, gptr b)
 STATIC void
 S_qsortsv(pTHX_ gptr *list1, size_t nmemb, SVCOMPARE_t cmp)
 {
-    SV **hintsvp;
+    SV *hintsv;
 
-    if (SORTHINTS(hintsvp) & HINT_SORT_STABLE) {
+    if (SORTHINTS(hintsv) & HINT_SORT_STABLE) {
 	 register gptr **pp, *q;
 	 register size_t n, j, i;
 	 gptr *small[SMALLSORT], **indir, tmp;
@@ -1391,7 +1390,7 @@ Perl_sortsv(pTHX_ SV **array, size_t nmemb, SVCOMPARE_t cmp)
 {
     void (*sortsvp)(pTHX_ SV **array, size_t nmemb, SVCOMPARE_t cmp) =
         S_mergesortsv;
-    SV **hintsvp;
+    SV *hintsv;
     I32 hints;
 
     /*  Sun's Compiler (cc: WorkShop Compilers 4.2 30 Oct 1996 C 4.2) used 
@@ -1399,7 +1398,7 @@ Perl_sortsv(pTHX_ SV **array, size_t nmemb, SVCOMPARE_t cmp)
 	errors related to picking the correct sort() function, try recompiling 
 	this file without optimiziation.  -- A.D.  4/2002.
     */
-    hints = SORTHINTS(hintsvp);
+    hints = SORTHINTS(hintsv);
     if (hints & HINT_SORT_QUICKSORT) {
 	sortsvp = S_qsortsv;
     }

scope.c

@@ -959,6 +959,10 @@ Perl_leave_scope(pTHX_ I32 base)
 	    PL_op = (OP*)SSPOPPTR;
 	    break;
 	case SAVEt_HINTS:
+	    if ((PL_hints & HINT_LOCALIZE_HH) && GvHV(PL_hintgv)) {
+		SvREFCNT_dec((SV*)GvHV(PL_hintgv));
+		GvHV(PL_hintgv) = NULL;
+	    }
 	    *(I32*)&PL_hints = (I32)SSPOPINT;
 	    break;
 	case SAVEt_COMPPAD:

t/comp/hints.t

@@ -0,0 +1,36 @@
+#!./perl -w
+
+BEGIN { print "1..7\n"; }
+BEGIN {
+    print "not " if exists $^H{foo};
+    print "ok 1 - \$^H{foo} doesn't exist initially\n";
+}
+{
+    # simulate a pragma -- don't forget HINT_LOCALIZE_HH
+    BEGIN { $^H |= 0x00020000; $^H{foo} = "a"; }
+    BEGIN {
+	print "not " if $^H{foo} ne "a";
+	print "ok 2 - \$^H{foo} is now 'a'\n";
+    }
+    {
+	BEGIN { $^H |= 0x00020000; $^H{foo} = "b"; }
+	BEGIN {
+	    print "not " if $^H{foo} ne "b";
+	    print "ok 3 - \$^H{foo} is now 'b'\n";
+	}
+    }
+    BEGIN {
+	print "not " if $^H{foo} ne "a";
+	print "ok 4 - \$H^{foo} restored to 'a'\n";
+    }
+    CHECK {
+	print "not " if exists $^H{foo};
+	print "ok 6 - \$^H{foo} doesn't exist when compilation complete\n";
+    }
+    print "not " if exists $^H{foo};
+    print "ok 7 - \$^H{foo} doesn't exist at runtime\n";
+}
+BEGIN {
+    print "not " if exists $^H{foo};
+    print "ok 5 - \$^H{foo} doesn't exist while finishing compilation\n";
+}