[gcc r12-2227] coroutines: Fix a typo in rewriting the function.

[Iain D Sandoe <iains@gcc.gnu.org>]

https://gcc.gnu.org/g:0d5db79a61af150cba48612c9fbc3267262adb93

commit r12-2227-g0d5db79a61af150cba48612c9fbc3267262adb93
Author: Iain Sandoe <iain@sandoe.co.uk>
Date:   Wed Jun 23 08:13:22 2021 +0100

    coroutines: Fix a typo in rewriting the function.
    
    When amending the function re-write code, I made a typo in
    the block connections.  This has not shown up in any test
    fails (as far as can be seen) but is a regression in debug
    info.
    
    Fixed thus.
    
    Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
    
    gcc/cp/ChangeLog:
    
            * coroutines.cc
            (coro_rewrite_function_body): Connect the replacement
            function block to the block nest correctly.

Diff:
---
 gcc/cp/coroutines.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/gcc/cp/coroutines.cc b/gcc/cp/coroutines.cc
index a1b0b31f497..f5ae2d6d101 100644
--- a/gcc/cp/coroutines.cc
+++ b/gcc/cp/coroutines.cc
@@ -4055,8 +4055,8 @@ coro_rewrite_function_body (location_t fn_start, tree fnbody, tree orig,
       BIND_EXPR_BLOCK (first) = replace_blk;
       /* The top block has one child, so far, and we have now got a 
 	 superblock.  */
-      BLOCK_SUPERCONTEXT (block) = top_block;
-      BLOCK_SUBBLOCKS (top_block) = block;
+      BLOCK_SUPERCONTEXT (replace_blk) = top_block;
+      BLOCK_SUBBLOCKS (top_block) = replace_blk;
     }
 
   /* Wrap the function body in a try {} catch (...) {} block, if exceptions