diff --git a/dist/Safe/t/safeops.t b/dist/Safe/t/safeops.t
index ea159316009c..57c46b62c3ee 100644
--- a/dist/Safe/t/safeops.t
+++ b/dist/Safe/t/safeops.t
@@ -453,7 +453,7 @@ dor		$x // $y
 dorassign	$x //= $y
 once		SKIP {use feature 'state'; state $foo = 42;}
 say		SKIP {use feature 'say'; say "foo";}
-smartmatch	no warnings 'experimental::smartmatch'; $x ~~ $y
+smartmatch	no warnings 'deprecated'; $x ~~ $y
 aeach		SKIP each @t
 akeys		SKIP keys @t
 avalues		SKIP values @t
diff --git a/lib/B/Deparse.t b/lib/B/Deparse.t
index c7a3307a9ab8..ae1372f63050 100644
--- a/lib/B/Deparse.t
+++ b/lib/B/Deparse.t
@@ -1061,7 +1061,7 @@ my $c = [];
 my $d = \[];
 ####
 # SKIP ?$] < 5.010 && "smartmatch and given/when not implemented on this Perl version"
-# CONTEXT use feature ':5.10'; no warnings 'experimental::smartmatch';
+# CONTEXT use feature ':5.10'; no warnings 'deprecated';
 # implicit smartmatch in given/when
 given ('foo') {
     when ('bar') { continue; }
@@ -1624,7 +1624,7 @@ my @a;
 $a[0] = 1;
 ####
 # feature features without feature
-# CONTEXT no warnings 'experimental::smartmatch';
+# CONTEXT no warnings 'deprecated';
 CORE::state $x;
 CORE::say $x;
 CORE::given ($x) {
@@ -1640,7 +1640,7 @@ CORE::evalbytes '';
 () = CORE::fc $x;
 ####
 # feature features when feature has been disabled by use VERSION
-# CONTEXT no warnings 'experimental::smartmatch';
+# CONTEXT no warnings 'deprecated';
 use feature (sprintf(":%vd", $^V));
 use 1;
 CORE::say $_;
@@ -1670,7 +1670,7 @@ CORE::evalbytes '';
 () = CORE::__SUB__;
 ####
 # (the above test with CONTEXT, and the output is equivalent but different)
-# CONTEXT use feature ':5.10'; no warnings 'experimental::smartmatch';
+# CONTEXT use feature ':5.10'; no warnings 'deprecated';
 # feature features when feature has been disabled by use VERSION
 use feature (sprintf(":%vd", $^V));
 use 1;
@@ -1704,7 +1704,7 @@ CORE::evalbytes '';
 ####
 # SKIP ?$] < 5.017004 && "lexical subs not implemented on this Perl version"
 # lexical subroutines and keywords of the same name
-# CONTEXT use feature 'lexical_subs', 'switch'; no warnings 'experimental';
+# CONTEXT use feature 'lexical_subs', 'switch'; no warnings 'experimental'; no warnings 'deprecated';
 my sub default;
 my sub else;
 my sub elsif;
diff --git a/lib/overload.t b/lib/overload.t
index 3a2b50ed9225..adb57d3ee20d 100644
--- a/lib/overload.t
+++ b/lib/overload.t
@@ -1910,7 +1910,7 @@ foreach my $op (qw(<=> == != < <= > >=)) {
 
 
 	for my $sub (keys %subs) {
-	    no warnings 'experimental::smartmatch';
+	    no warnings 'deprecated';
 	    my $term = $subs{$sub};
 	    my $t = sprintf $term, '$_[0][0]';
 	    my $e ="sub { \$funcs .= '($sub)'; my \$r; if (\$use_int) {"
@@ -1952,7 +1952,7 @@ foreach my $op (qw(<=> == != < <= > >=)) {
 				    ? "-\$_[0][0]"
 				    : "$_[3](\$_[0][0])";
 			my $r;
-			no warnings 'experimental::smartmatch';
+			no warnings 'deprecated';
 			if ($use_int) {
 			    use integer; $r = eval $e;
 			}
@@ -1999,7 +1999,7 @@ foreach my $op (qw(<=> == != < <= > >=)) {
 	    $use_int = ($int ne '');
 	    my $plain = $tainted_val;
 	    my $plain_term = $int . sprintf $sub_term, '$plain';
-	    my $exp = do {no warnings 'experimental::smartmatch'; eval $plain_term };
+	    my $exp = do {no warnings 'deprecated'; eval $plain_term };
 	    diag("eval of plain_term <$plain_term> gave <$@>") if $@;
 	    SKIP: {
 		is_if_taint_supported(tainted($exp), $exp_taint,
@@ -2029,7 +2029,7 @@ foreach my $op (qw(<=> == != < <= > >=)) {
 
 		    my $res_term  = $int . sprintf $sub_term, $var;
 		    my $desc =  "<$res_term> $ov_pkg" ;
-		    my $res = do { no warnings 'experimental::smartmatch'; eval $res_term };
+		    my $res = do { no warnings 'deprecated'; eval $res_term };
 		    diag("eval of res_term $desc gave <$@>") if $@;
 		    # uniquely, the inc/dec ops return the original
 		    # ref rather than a copy, so stringify it to
diff --git a/t/lib/croak/pp_ctl b/t/lib/croak/pp_ctl
index de0221b57d32..a63cbd78491e 100644
--- a/t/lib/croak/pp_ctl
+++ b/t/lib/croak/pp_ctl
@@ -41,7 +41,7 @@ EXPECT
 Can't find label foo at - line 3.
 ########
 # NAME when outside given
-use 5.01; no warnings 'experimental::smartmatch';
+use 5.01; no warnings 'deprecated';
 when(undef){}
 EXPECT
 Can't "when" outside a topicalizer at - line 2.
diff --git a/t/lib/feature/switch b/t/lib/feature/switch
index 0dee7f51cf91..4d379ea21322 100644
--- a/t/lib/feature/switch
+++ b/t/lib/feature/switch
@@ -3,28 +3,28 @@ Check the lexical scoping of the switch keywords.
 
 __END__
 # No switch; given should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 print STDOUT given;
 EXPECT
 Unquoted string "given" may clash with future reserved word at - line 3.
 given
 ########
 # No switch; when should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 print STDOUT when;
 EXPECT
 Unquoted string "when" may clash with future reserved word at - line 3.
 when
 ########
 # No switch; default should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 print STDOUT default;
 EXPECT
 Unquoted string "default" may clash with future reserved word at - line 3.
 default
 ########
 # No switch; break should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 print STDOUT break;
 EXPECT
 Unquoted string "break" may clash with future reserved word at - line 3.
@@ -36,19 +36,19 @@ EXPECT
 Can't "continue" outside a when block at - line 2.
 ########
 # Use switch; so given is a keyword
-use feature 'switch'; no warnings 'experimental::smartmatch';
+use feature 'switch'; no warnings 'deprecated';
 given("okay\n") { print }
 EXPECT
 okay
 ########
 # Use switch; so when is a keyword
-use feature 'switch'; no warnings 'experimental::smartmatch';
+use feature 'switch'; no warnings 'deprecated';
 given(1) { when(1) { print "okay" } }
 EXPECT
 okay
 ########
 # Use switch; so default is a keyword
-use feature 'switch'; no warnings 'experimental::smartmatch';
+use feature 'switch'; no warnings 'deprecated';
 given(1) { default { print "okay" } }
 EXPECT
 okay
@@ -60,7 +60,7 @@ EXPECT
 Can't "break" outside a given block at - line 3.
 ########
 # switch out of scope; given should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 { use feature 'switch';
   given (1) {print "Okay here\n";}
 }
@@ -71,7 +71,7 @@ Okay here
 given
 ########
 # switch out of scope; when should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 { use feature 'switch';
   given (1) { when(1) {print "Okay here\n";} }
 }
@@ -82,7 +82,7 @@ Okay here
 when
 ########
 # switch out of scope; default should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 { use feature 'switch';
   given (1) { default {print "Okay here\n";} }
 }
@@ -93,7 +93,7 @@ Okay here
 default
 ########
 # switch out of scope; break should be a bareword.
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 { use feature 'switch';
   given (1) { break }  
 }
@@ -103,7 +103,7 @@ Unquoted string "break" may clash with future reserved word at - line 6.
 break
 ########
 # C<no feature 'switch'> should work
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 use feature 'switch';
 given (1) { when(1) {print "Okay here\n";} }
 no feature 'switch';
@@ -114,7 +114,7 @@ Okay here
 when
 ########
 # C<no feature> should work too
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 use feature 'switch';
 given (1) { when(1) {print "Okay here\n";} }
 no feature;
@@ -125,14 +125,14 @@ Okay here
 when
 ########
 # Without the feature, no 'Unambiguous use of' warning:
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 @break = ($break = "break");
 print ${break}, ${break[0]};
 EXPECT
 breakbreak
 ########
 # With the feature, we get an 'Unambiguous use of' warning:
-use warnings; no warnings 'experimental::smartmatch';
+use warnings; no warnings 'deprecated';
 use feature 'switch';
 @break = ($break = "break");
 print ${break}, ${break[0]};
diff --git a/t/lib/warnings/9uninit b/t/lib/warnings/9uninit
index 5c173fdb2ac8..0ceb0d240aa8 100644
--- a/t/lib/warnings/9uninit
+++ b/t/lib/warnings/9uninit
@@ -1943,7 +1943,7 @@ $v = 1 + prototype $fn;
 EXPECT
 Use of uninitialized value in addition (+) at - line 4.
 ########
-use warnings 'uninitialized'; no warnings 'experimental::smartmatch';
+use warnings 'uninitialized'; no warnings 'deprecated';
 my $v;
 my $fn = sub {};
 $v = 1 + (1 ~~ $fn);
diff --git a/t/lib/warnings/op b/t/lib/warnings/op
index 4ef9d565f198..d9de0a441f4c 100644
--- a/t/lib/warnings/op
+++ b/t/lib/warnings/op
@@ -363,7 +363,7 @@ OPTION fatal
 Can't use an array as a reference at - line 3.
 ########
 # op.c
-use warnings 'void' ; no warnings 'experimental::smartmatch'; close STDIN ;
+use warnings 'void' ; no warnings 'deprecated'; close STDIN ;
 #line 2
 1 x 3 ;			# OP_REPEAT (folded)
 (1) x 3 ;		# OP_REPEAT
diff --git a/t/op/cmpchain.t b/t/op/cmpchain.t
index 48aaabf1e5b7..13672b836c09 100644
--- a/t/op/cmpchain.t
+++ b/t/op/cmpchain.t
@@ -7,7 +7,6 @@ BEGIN {
 }
 
 use feature "isa";
-no warnings qw(experimental::smartmatch);
 
 my @cheqop = qw(== != eq ne);
 my @nceqop = qw(<=> cmp ~~);
@@ -15,18 +14,21 @@ my @chrelop = qw(< > <= >= lt gt le ge);
 my @ncrelop = qw(isa);
 
 foreach my $c0 (@nceqop) {
+    no warnings qw(deprecated);
     foreach my $c1 (@nceqop) {
 	is eval("sub { \$a $c0 \$b $c1 \$c }"), undef,
 	    "$c0 $c1 non-associative";
     }
 }
 foreach my $c (@nceqop) {
+    no warnings qw(deprecated);
     foreach my $e (@cheqop) {
 	is eval("sub { \$a $c \$b $e \$c }"), undef, "$c $e non-associative";
 	is eval("sub { \$a $e \$b $c \$c }"), undef, "$e $c non-associative";
     }
 }
 foreach my $c (@nceqop) {
+    no warnings qw(deprecated);
     foreach my $e0 (@cheqop) {
 	foreach my $e1 (@cheqop) {
 	    is eval("sub { \$a $c \$b $e0 \$c $e1 \$d }"), undef,
diff --git a/t/op/coreamp.t b/t/op/coreamp.t
index ca39c2c555a4..588b4ed50552 100644
--- a/t/op/coreamp.t
+++ b/t/op/coreamp.t
@@ -15,8 +15,6 @@ BEGIN {
   $^P |= 0x100; # Provide informative "file" names for evals
 }
 
-no warnings 'experimental::smartmatch';
-
 sub lis($$;$) {
   &is(map(@$_ ? "[@{[map $_//'~~u~~', @$_]}]" : 'nought', @_[0,1]), $_[2]);
 }
@@ -375,6 +373,7 @@ test_proto 'break';
 {
   $tests ++;
   my $tmp;
+  no warnings 'deprecated';
   CORE::given(1) {
     CORE::when(1) {
       &mybreak;
@@ -463,6 +462,7 @@ SKIP:
 
 test_proto 'continue';
 $tests ++;
+no warnings 'deprecated';
 CORE::given(1) {
   CORE::when(1) {
     &mycontinue();
diff --git a/t/op/smartmatch.t b/t/op/smartmatch.t
index 10d35390d79e..ca85d15785c2 100644
--- a/t/op/smartmatch.t
+++ b/t/op/smartmatch.t
@@ -8,7 +8,7 @@ BEGIN {
 use strict;
 use warnings;
 no warnings 'uninitialized';
-no warnings 'experimental::smartmatch';
+no warnings 'deprecated';    # smartmatch is deprecated and will be removed in 5.042
 
 ++$|;
 
@@ -146,7 +146,7 @@ sub NOT_DEF() { undef }
   # re-introduced it will probably crash in one of the many smoke
   # builds.
   fresh_perl_is('print (q(x) ~~ q(x)) | (/x/ ~~ %!)', "1",
-		{ switches => [ "-MErrno", "-M-warnings=experimental::smartmatch" ] },
+		{ switches => [ "-MErrno", "-M-warnings=deprecated" ] },
 		 "don't fill the stack with rubbish");
 }
 
@@ -194,10 +194,10 @@ sub NOT_DEF() { undef }
     # if there was some other operator's arguments left on the stack, as with
     # the test cases.
     fresh_perl_is('print(0->[0 =~ qr/1/ ~~ 0])', '',
-                  { switches => [ "-M-warnings=experimental::smartmatch" ] },
+                  { switches => [ "-M-warnings=deprecated" ] },
                   "don't qr-ify left-side match against a stacked argument");
     fresh_perl_is('print(0->[0 ~~ (0 =~ qr/1/)])', '',
-                  { switches => [ "-M-warnings=experimental::smartmatch" ] },
+                  { switches => [ "-M-warnings=deprecated" ] },
                   "don't qr-ify right-side match against a stacked argument");
 }
 
diff --git a/t/op/state.t b/t/op/state.t
index 7aef435ffdc4..747e316f226a 100644
--- a/t/op/state.t
+++ b/t/op/state.t
@@ -346,7 +346,7 @@ foreach my $x (0 .. 4) {
 #
 my @spam = qw [spam ham bacon beans];
 foreach my $spam (@spam) {
-    no warnings 'experimental::smartmatch';
+    no warnings 'deprecated';
     given (state $spam = $spam) {
         when ($spam [0]) {ok 1, "given"}
         default          {ok 0, "given"}
diff --git a/t/op/switch.t b/t/op/switch.t
index dbfd906e2a2d..e1c079956f0d 100644
--- a/t/op/switch.t
+++ b/t/op/switch.t
@@ -8,7 +8,7 @@ BEGIN {
 
 use strict;
 use warnings;
-no warnings 'experimental::smartmatch';
+no warnings 'deprecated';
 
 plan tests => 197;
 
diff --git a/t/op/taint.t b/t/op/taint.t
index b4b590ef5d3d..daeb164efafe 100644
--- a/t/op/taint.t
+++ b/t/op/taint.t
@@ -2453,6 +2453,7 @@ EOF
 	my $desc = "tainted value returned from " . shift(@descriptions);
 
 	my $res = do {
+	    no warnings 'deprecated';
 	    given ($_) {
 		when ('x') { $letter }
 		when ('y') { goto leavegiven }
@@ -2482,7 +2483,7 @@ EOF
 # Tainted values with smartmatch
 # [perl #93590] S_do_smartmatch stealing its own string buffers
 {
-no warnings 'experimental::smartmatch';
+no warnings 'deprecated';
 ok "M$TAINT" ~~ ['m', 'M'], '$tainted ~~ ["whatever", "match"]';
 ok !("M$TAINT" ~~ ['m', undef]), '$tainted ~~ ["whatever", undef]';
 }
diff --git a/t/op/tie_fetch_count.t b/t/op/tie_fetch_count.t
index d8b906d7ab45..86505f6eba85 100644
--- a/t/op/tie_fetch_count.t
+++ b/t/op/tie_fetch_count.t
@@ -165,7 +165,7 @@ $_ = "foo";
 $dummy  =  $var =~ m/ / ; check_count 'm//';
 $dummy  =  $var =~ s/ //; check_count 's///';
 {
-    no warnings 'experimental::smartmatch';
+    no warnings 'deprecated';
     $dummy  =  $var ~~    1 ; check_count '~~';
 }
 $dummy  =  $var =~ y/ //; check_count 'y///';