diff --git a/libstdc++-v3/include/bits/deque.tcc b/libstdc++-v3/include/bits/deque.tcc
index c15b046691e..20b23fffc9e 100644
--- a/libstdc++-v3/include/bits/deque.tcc
+++ b/libstdc++-v3/include/bits/deque.tcc
@@ -381,7 +381,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 
       const difference_type __back_capacity
 	= (this->_M_impl._M_finish._M_last - this->_M_impl._M_finish._M_cur);
-      if (__front_capacity + __back_capacity < _S_buffer_size())
+      if (size_type(__front_capacity + __back_capacity) < _S_buffer_size())
 	return false;
 
       return std::__shrink_to_fit_aux<deque>::_S_do_it(*this);
diff --git a/libstdc++-v3/include/std/spanstream b/libstdc++-v3/include/std/spanstream
index 23a340a746e..fbb40ff1db2 100644
--- a/libstdc++-v3/include/std/spanstream
+++ b/libstdc++-v3/include/std/spanstream
@@ -152,7 +152,7 @@ template<typename _CharT, typename _Traits>
 
       if (__way == ios_base::beg)
 	{
-	  if (0 <= __off && __off <= _M_buf.size())
+	  if (0 <= __off && (size_t)__off <= _M_buf.size())
 	    {
 	      if (__which & ios_base::in)
 		this->setg(this->eback(), this->eback() + __off, this->egptr());
@@ -188,7 +188,7 @@ template<typename _CharT, typename _Traits>
 	  if (__builtin_add_overflow(__base, __off, &__off)) [[unlikely]]
 	    return __ret;
 
-	  if (__off < 0 || __off > _M_buf.size()) [[unlikely]]
+	  if (__off < 0 || (size_t)__off > _M_buf.size()) [[unlikely]]
 	    return __ret;
 
 	  if (__which & ios_base::in)