merge revision(s) ce7a053475cbebfb2f3e5ed6614e0ba631541917,1cbb1f1720127b0b34b38c77e27b51b182008699: [Backport #16695]

	Adjust sp for `x = false; y = (return until x unless x)` [Bug #16695]

	---
	 compile.c                | 8 +++-----
	 test/ruby/test_syntax.rb | 9 +++++++++
	 2 files changed, 12 insertions(+), 5 deletions(-)

	test/ruby/test_syntax.rb: avoid "warning: assigned but unused
	 variable"

	---
	 test/ruby/test_syntax.rb | 2 +-
	 1 file changed, 1 insertion(+), 1 deletion(-)

1 files changed, 3 insertions, 5 deletions

diff --git a/compile.c b/compile.c
index 5f86a5bd67..c05a4a0804 100644
--- a/compile.c
+++ b/compile.c
@@ -2737,7 +2737,6 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
 	    goto again;
 	}
         else if (IS_INSN_ID(diobj, leave)) {
-	    INSN *pop;
 	    /*
 	     *  jump LABEL
 	     *  ...
@@ -2745,7 +2744,6 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
 	     *  leave
 	     * =>
 	     *  leave
-	     *  pop
 	     *  ...
 	     * LABEL:
 	     *  leave
@@ -2755,9 +2753,6 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
             iobj->insn_id = BIN(leave);
 	    iobj->operand_size = 0;
 	    iobj->insn_info = diobj->insn_info;
-	    /* adjust stack depth */
-	    pop = new_insn_body(iseq, diobj->insn_info.line_no, BIN(pop), 0);
-            ELEM_INSERT_NEXT(&iobj->link, &pop->link);
 	    goto again;
 	}
        else if (IS_INSN(iobj->link.prev) &&
@@ -5247,6 +5242,9 @@ compile_if(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, int
 		branches);
 	    end_label = NEW_LABEL(line);
 	    ADD_INSNL(then_seq, line, jump, end_label);
+            if (!popped) {
+                ADD_INSN(then_seq, line, pop);
+            }
 	}
 	ADD_SEQ(ret, then_seq);
     }