[gcc r10-11463] libstdc++: Tweaks to <regex> to avoid warnings

[Jonathan Wakely <redi@gcc.gnu.org>]

https://gcc.gnu.org/g:884751cc4f24ae92f550a4733632e9c54e7182d8

commit r10-11463-g884751cc4f24ae92f550a4733632e9c54e7182d8
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Mon Sep 27 20:44:24 2021 +0100

    libstdc++: Tweaks to <regex> to avoid warnings
    
    Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
    
    libstdc++-v3/ChangeLog:
    
            * include/bits/regex_compiler.tcc: Add line break in empty while
            statement.
            * include/bits/regex_executor.tcc: Avoid unused parameter
            warning.
    
    (cherry picked from commit b5f276b8c76d892f7fed229153cfbadc13f4696e)

Diff:
---
 libstdc++-v3/include/bits/regex_compiler.tcc | 6 ++++--
 libstdc++-v3/include/bits/regex_executor.tcc | 2 +-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/libstdc++-v3/include/bits/regex_compiler.tcc b/libstdc++-v3/include/bits/regex_compiler.tcc
index d29a0537283..3667c860690 100644
--- a/libstdc++-v3/include/bits/regex_compiler.tcc
+++ b/libstdc++-v3/include/bits/regex_compiler.tcc
@@ -140,7 +140,8 @@ namespace __detail
 	return true;
       if (this->_M_atom())
 	{
-	  while (this->_M_quantifier());
+	  while (this->_M_quantifier())
+	    ;
 	  return true;
 	}
       return false;
@@ -440,7 +441,8 @@ namespace __detail
 	      __last_char.second = '-';
 	    }
 	}
-      while (_M_expression_term(__last_char, __matcher));
+      while (_M_expression_term(__last_char, __matcher))
+	;
       if (__last_char.first)
 	__matcher._M_add_char(__last_char.second);
       __matcher._M_ready();
diff --git a/libstdc++-v3/include/bits/regex_executor.tcc b/libstdc++-v3/include/bits/regex_executor.tcc
index 5c8f8492de1..352f24bf306 100644
--- a/libstdc++-v3/include/bits/regex_executor.tcc
+++ b/libstdc++-v3/include/bits/regex_executor.tcc
@@ -423,7 +423,7 @@ namespace __detail
   template<typename _BiIter, typename _Alloc, typename _TraitsT,
 	   bool __dfs_mode>
     void _Executor<_BiIter, _Alloc, _TraitsT, __dfs_mode>::
-    _M_handle_accept(_Match_mode __match_mode, _StateIdT __i)
+    _M_handle_accept(_Match_mode __match_mode, _StateIdT)
     {
       if (__dfs_mode)
 	{