Companion to #16601: cxinc would create uninitialized

PERL_CONTEXTs.  The bug was tickled by the test
lib/Math/BigInt/t/upgrade.t, the new test of recurse.t
added to check that I got the context stack extension right.
Also rewrite recurse.t to use test.pl.

p4raw-id: //depot/perl@16679

diff --git a/scope.c b/scope.c
index 4ff903f..5ae9a31 100644 (file)
--- a/scope.c
+++ b/scope.c
@@ -80,8 +80,8 @@ Perl_new_stackinfo(pTHX_ I32 stitems, I32 cxitems)
     si->si_cxmax = cxitems - 1;
     si->si_cxix = -1;
     si->si_type = PERLSI_UNDEF;
-    /* Needs to be Newz() because PUSHSUBST() in pp_subst()
-     * might otherwise read uninitialized heap. */
+    /* Needs to be Newz() instead of New() because PUSHSUBST()
+     * in pp_subst() might otherwise read uninitialized heap. */
     Newz(56, si->si_cxstack, cxitems, PERL_CONTEXT);
     return si;
 }
@@ -89,8 +89,13 @@ Perl_new_stackinfo(pTHX_ I32 stitems, I32 cxitems)
 I32
 Perl_cxinc(pTHX)
 {
+    IV old_max = cxstack_max;
     cxstack_max = GROW(cxstack_max);
     Renew(cxstack, cxstack_max + 1, PERL_CONTEXT);     /* XXX should fix CXINC macro */
+    /* Needs to Zero()ed because otherwise deep enough recursion
+     * (such as in lib/Math/BigInt/t/upgrade.t) will end up reading
+     * uninitialized heap. */
+    Zero(cxstack + old_max + 1, cxstack_max - old_max, PERL_CONTEXT);
     return cxstack_ix + 1;
 }
 

diff --git a/t/op/recurse.t b/t/op/recurse.t
index dc823ed..a86744e 100755 (executable)
--- a/t/op/recurse.t
+++ b/t/op/recurse.t
@@ -4,19 +4,26 @@
 # test recursive functions.
 #
 
-print "1..25\n";
+BEGIN {
+    chdir 't' if -d 't';
+    @INC = qw(. ../lib);
+    require "test.pl";
+    plan(tests => 26);
+}
+
+use strict;
 
-sub gcd ($$) {
+sub gcd {
     return gcd($_[0] - $_[1], $_[1]) if ($_[0] > $_[1]);
     return gcd($_[0], $_[1] - $_[0]) if ($_[0] < $_[1]);
     $_[0];
 }
 
-sub factorial ($) {
+sub factorial {
     $_[0] < 2 ? 1 : $_[0] * factorial($_[0] - 1);
 }
 
-sub fibonacci ($) {
+sub fibonacci {
     $_[0] < 2 ? 1 : fibonacci($_[0] - 2) + fibonacci($_[0] - 1);
 }
 
@@ -26,7 +33,7 @@ sub fibonacci ($) {
 # For example ackermann(4,1) will take quite a long time.
 # It will simply eat away your memory. Trust me.
 
-sub ackermann ($$) {
+sub ackermann {
     return $_[1] + 1               if ($_[0] == 0);
     return ackermann($_[0] - 1, 1) if ($_[1] == 0);
     ackermann($_[0] - 1, ackermann($_[0], $_[1] - 1));
@@ -34,7 +41,7 @@ sub ackermann ($$) {
 
 # Highly recursive, highly boring.
 
-sub takeuchi ($$$) {
+sub takeuchi {
     $_[1] < $_[0] ?
        takeuchi(takeuchi($_[0] - 1, $_[1], $_[2]),
                 takeuchi($_[1] - 1, $_[2], $_[0]),
@@ -42,48 +49,30 @@ sub takeuchi ($$$) {
            : $_[2];
 }
 
-print 'not ' unless (($d = gcd(1147, 1271)) == 31);
-print "ok 1\n";
-print "# gcd(1147, 1271) = $d\n";
-
-print 'not ' unless (($d = gcd(1908, 2016)) == 36);
-print "ok 2\n";
-print "# gcd(1908, 2016) = $d\n";
+is(gcd(1147, 1271), 31, "gcd(1147, 1271)");
 
-print 'not ' unless (($f = factorial(10)) == 3628800);
-print "ok 3\n";
-print "# factorial(10) = $f\n";
+is(gcd(1908, 2016), 36, "gcd(1908, 2016)");
 
-print 'not ' unless (($f = factorial(factorial(3))) == 720);
-print "ok 4\n";
-print "# factorial(factorial(3)) = $f\n";
+is(factorial(10), 3628800, "factorial(10)");
 
-print 'not ' unless (($f = fibonacci(10)) == 89);
-print "ok 5\n";
-print "# fibonacci(10) = $f\n";
+is(factorial(factorial(3)), 720, "factorial(factorial(3))");
 
-print 'not ' unless (($f = fibonacci(fibonacci(7))) == 17711);
-print "ok 6\n";
-print "# fibonacci(fibonacci(7)) = $f\n";
+is(fibonacci(10), 89, "fibonacci(10)");
 
-$i = 7;
+is(fibonacci(fibonacci(7)), 17711, "fibonacci(fibonacci(7))");
 
-@ack = qw(1 2 3 4 2 3 4 5 3 5 7 9 5 13 29 61);
+my @ack = qw(1 2 3 4 2 3 4 5 3 5 7 9 5 13 29 61);
 
-for $x (0..3) { 
-    for $y (0..3) {
-       $a = ackermann($x, $y);
-       print 'not ' unless ($a == shift(@ack));
-       print "ok ", $i++, "\n";
-       print "# ackermann($x, $y) = $a\n";
+for my $x (0..3) { 
+    for my $y (0..3) {
+       my $a = ackermann($x, $y);
+       is($a, shift(@ack), "ackermann($x, y)");
     }
 }
 
-($x, $y, $z) = (18, 12, 6);
+my ($x, $y, $z) = (18, 12, 6);
 
-print 'not ' unless (($t = takeuchi($x, $y, $z)) == $z + 1);
-print "ok ", $i++, "\n";
-print "# takeuchi($x, $y, $z) = $t\n";
+is(takeuchi($x, $y, $z), $z + 1, "takeuchi($x, $y, $z) == $z + 1");
 
 {
     sub get_first1 {
@@ -91,12 +80,12 @@ print "# takeuchi($x, $y, $z) = $t\n";
     }
 
     sub get_list1 {
-       return [24] unless $_[0];
+       return [curr_test] unless $_[0];
        my $u = get_first1(0);
        [$u];
     }
     my $x = get_first1(1);
-    print "ok $x\n";
+    ok($x, "premature FREETMPS (change 5699)");
 }
 
 {
@@ -105,12 +94,24 @@ print "# takeuchi($x, $y, $z) = $t\n";
     }
 
     sub get_list2 {
-       return [25] unless $_[0];
+       return [curr_test] unless $_[0];
        my $u = get_first2(0);
        return [$u];
     }
     my $x = get_first2(1);
-    print "ok $x\n";
+    ok($x, "premature FREETMPS (change 5699)");
+}
+
+{
+    local $^W = 0; # We do not need recursion depth warning.
+
+    sub sillysum {
+       return $_[0] + ($_[0] > 0 ? sillysum($_[0] - 1) : 0);
+    }
+
+    is(sillysum(1000), 1000*1001/2, "recursive sum of 1..1000");
 }
 
-$i = 26;
+
+
+