[4.0 PATCH] Fix for PR21951

[Dan Kegel <dank at kegel dot com>]

C++ programs compiled with -fno-exceptions fail with gcc-4.0.0
because of false positive warnings about control reaching
the end of a inlined function without returning a value
(see http://gcc.gnu.org/PR21951).

While user code can easily work around this, it also
affects five include files in libstdc++.  Shops that compile everything
with -Werror -fno-exceptions will not be able to use
gcc-4.0.0 without a fix like the following (also attached to the PR).
It fixes the problem for me, and doesn't cause any
obvious trouble when building or testing g++.

I don't have a copyright assignment, but as the patch is
rather trivial, perhaps it or something similar can be applied anyway
in time for 4.0.1 or 4.0.2.

Thanks!
- Dan

2005-06-11  Dan Kegel <dank@kegel.com>

	PR c++/21951: avoid appearing to hit end of function when compiled with -fno-exceptions
	* libstdc++-v3/include/bits/stl_vector.h
	* libstdc++-v3/include/bits/stl_uninitialized.h
	* libstdc++-v3/include/ext/rope
	* libstdc++-v3/include/ext/memory
	* libstdc++-v3/include/ext/hashtable.h



--- gcc-4.0.1-20050607/libstdc++-v3/include/bits/stl_vector.h.old	2005-06-11 03:58:20.000000000 -0700
+++ gcc-4.0.1-20050607/libstdc++-v3/include/bits/stl_vector.h	2005-06-11 04:01:21.000000000 -0700
@@ -765,13 +765,13 @@
 	    {
 	      std::__uninitialized_copy_a(__first, __last, __result,
 					  this->get_allocator());
-	      return __result;
 	    }
 	  catch(...)
 	    {
 	      _M_deallocate(__result, __n);
 	      __throw_exception_again;
 	    }
+	  return __result;
 	}


--- gcc-4.0.1-20050607/libstdc++-v3/include/bits/stl_uninitialized.h.old	2005-06-11 03:58:20.000000000 -0700
+++ gcc-4.0.1-20050607/libstdc++-v3/include/bits/stl_uninitialized.h	2005-06-11 04:05:18.990003248 -0700
@@ -84,13 +84,13 @@
 	{
 	  for (; __first != __last; ++__first, ++__cur)
 	    std::_Construct(&*__cur, *__first);
-	  return __cur;
 	}
       catch(...)
 	{
 	  std::_Destroy(__result, __cur);
 	  __throw_exception_again;
 	}
+      return __cur;
     }

   /**
@@ -236,13 +236,13 @@
 	{
 	  for (; __first != __last; ++__first, ++__cur)
 	    __alloc.construct(&*__cur, *__first);
-	  return __cur;
 	}
       catch(...)
 	{
 	  std::_Destroy(__result, __cur, __alloc);
 	  __throw_exception_again;
 	}
+      return __cur;
     }

   template<typename _InputIterator, typename _ForwardIterator, typename _Tp>
@@ -337,11 +337,13 @@
 	{
 	  return std::__uninitialized_copy_a(__first2, __last2, __mid, __alloc);
 	}
+#ifdef __EXCEPTIONS  // work around http://gcc.gnu.org/PR21951 in gcc-4.0 only
       catch(...)
 	{
 	  std::_Destroy(__result, __mid, __alloc);
 	  __throw_exception_again;
 	}
+#endif
     }

   // __uninitialized_fill_copy
@@ -360,11 +362,13 @@
 	{
 	  return std::__uninitialized_copy_a(__first, __last, __mid, __alloc);
 	}
+#ifdef __EXCEPTIONS  // work around http://gcc.gnu.org/PR21951 in gcc-4.0 only
       catch(...)
 	{
 	  std::_Destroy(__result, __mid, __alloc);
 	  __throw_exception_again;
 	}
+#endif
     }

   // __uninitialized_copy_fill
--- gcc-4.0.1-20050607/libstdc++-v3/include/ext/rope.old	2005-06-11 03:58:20.000000000 -0700
+++ gcc-4.0.1-20050607/libstdc++-v3/include/ext/rope	2005-06-11 04:13:26.628870872 -0700
@@ -1645,11 +1645,13 @@
 	_S_cond_store_eos(__buf[__size]);
 	try
 	  { return _S_new_RopeLeaf(__buf, __size, __a); }
+#ifdef __EXCEPTIONS  // work around http://gcc.gnu.org/PR21951 in gcc-4.0 only
 	catch(...)
 	  {
 	    _RopeRep::__STL_FREE_STRING(__buf, __size, __a);
 	    __throw_exception_again;
 	  }
+#endif
       }

       // Concatenation of nonempty strings.
--- gcc-4.0.1-20050607/libstdc++-v3/include/ext/memory.old	2005-06-11 03:58:20.000000000 -0700
+++ gcc-4.0.1-20050607/libstdc++-v3/include/ext/memory	2005-06-11 04:13:52.897877376 -0700
@@ -85,11 +85,13 @@
 	    std::_Construct(&*__cur, *__first);
 	  return pair<_InputIter, _ForwardIter>(__first, __cur);
 	}
+#ifdef __EXCEPTIONS  // work around http://gcc.gnu.org/PR21951 in gcc-4.0 only
       catch(...)
 	{
 	  std::_Destroy(__result, __cur);
 	  __throw_exception_again;
 	}
+#endif
     }

   template<typename _RandomAccessIter, typename _Size, typename _ForwardIter>
@@ -144,11 +146,13 @@
 	    __alloc.construct(&*__cur, *__first);
 	  return pair<_InputIter, _ForwardIter>(__first, __cur);
 	}
+#ifdef __EXCEPTIONS  // work around http://gcc.gnu.org/PR21951 in gcc-4.0 only
       catch(...)
 	{
 	  std::_Destroy(__result, __cur, __alloc);
 	  __throw_exception_again;
 	}
+#endif
     }

   template<typename _InputIter, typename _Size, typename _ForwardIter,
--- gcc-4.0.1-20050607/libstdc++-v3/include/ext/hashtable.h.old	2005-06-11 03:58:20.000000000 -0700
+++ gcc-4.0.1-20050607/libstdc++-v3/include/ext/hashtable.h	2005-06-11 04:14:28.384482592 -0700
@@ -607,13 +607,13 @@
 	try
 	  {
 	    this->get_allocator().construct(&__n->_M_val, __obj);
-	    return __n;
 	  }
 	catch(...)
 	  {
 	    _M_put_node(__n);
 	    __throw_exception_again;
 	  }
+	return __n;
       }

       void


--
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