[gcc r11-8705] Revert "c++: Improve init handling"

[gcc r11-8705] Revert "c++: Improve init handling"

[Jason Merrill]

https://gcc.gnu.org/g:79663c962588e8c033ff39be39e938e2cc866e12

commit r11-8705-g79663c962588e8c033ff39be39e938e2cc866e12
Author: Jason Merrill <jason@redhat.com>
Date:   Wed Jul 7 17:57:40 2021 -0400

    Revert "c++: Improve init handling"
    
    Apparently looking through these codes means that in a template, we end up
    feeding a TARGET_EXPR to fold_non_dependent_expr, which should never
    happen.  This is a broader issue, but for now let's just revert the change.
    
    This reverts commit d9288bd28e24c755a7216311ee5247e7c88270a6.
    
            PR c++/101072
    
    gcc/cp/ChangeLog:
    
            * decl.c (check_initializer): Don't look through STMT_EXPR and
            BIND_EXPR.
    
    gcc/testsuite/ChangeLog:
    
            * g++.dg/cpp0x/constexpr-empty14.C: Add -fno-elide-constructors.

Diff:
---
 gcc/cp/decl.c                                  | 14 +++-----------
 gcc/testsuite/g++.dg/cpp0x/constexpr-empty14.C |  1 +
 2 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 0ed15f53596..9cfe62a98ee 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -7052,17 +7052,9 @@ check_initializer (tree decl, tree init, int flags, vec<tree, va_gc> **cleanups)
 	     have returned an INIT_EXPR rather than a CALL_EXPR.  In that
 	     case, pull the initializer back out and pass it down into
 	     store_init_value.  */
-	  while (true)
-	    {
-	      if (TREE_CODE (init_code) == EXPR_STMT
-		  || TREE_CODE (init_code) == STMT_EXPR
-		  || TREE_CODE (init_code) == CONVERT_EXPR)
-		init_code = TREE_OPERAND (init_code, 0);
-	      else if (TREE_CODE (init_code) == BIND_EXPR)
-		init_code = BIND_EXPR_BODY (init_code);
-	      else
-		break;
-	    }
+	  while (TREE_CODE (init_code) == EXPR_STMT
+		 || TREE_CODE (init_code) == CONVERT_EXPR)
+	    init_code = TREE_OPERAND (init_code, 0);
 	  if (TREE_CODE (init_code) == INIT_EXPR)
 	    {
 	      /* In C++20, the call to build_aggr_init could have created
diff --git a/gcc/testsuite/g++.dg/cpp0x/constexpr-empty14.C b/gcc/testsuite/g++.dg/cpp0x/constexpr-empty14.C
index ca4f9a55e5f..a2d498f82ae 100644
--- a/gcc/testsuite/g++.dg/cpp0x/constexpr-empty14.C
+++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-empty14.C
@@ -1,5 +1,6 @@
 // PR c++/91953
 // { dg-do compile { target c++11 } }
+// { dg-additional-options -fno-elide-constructors { target c++14_down } }
 
 struct S {};