2008-04-23 Johannes Singler <singler@ira.uka.de>

        * include/parallel/multiway_merge.h
        (multiway_merge_loser_tree):
        Leave checks to callers, add precondition instead.
        (multiway_merge_loser_tree_unguarded): Likewise.
        (multiway_merge_loser_tree_sentinel): Likewise.
        (sequential_multiway_merge): Added checks for total length 0.
        (parallel_multiway_merge): Skip empty sequences.
        (multiway_merge, all variants):
        Remove temporary variable, return directly.
        (stable_multiway_merge, all variants): Likewise.
        (multiway_merge_sentinels, all variants):  Likewise.
        (stable_multiway_merge_sentinels, all variants): Likewise.
        * include/parallel/multiseq_selection.h
        (multiseq_partition): More detailed assertions.

From-SVN: r134580

libstdc++-v3/ChangeLog

+2008-04-23  Johannes Singler  <singler@ira.uka.de>
+
+        * include/parallel/multiway_merge.h
+        (multiway_merge_loser_tree):
+        Leave checks to callers, add precondition instead.
+        (multiway_merge_loser_tree_unguarded): Likewise.
+        (multiway_merge_loser_tree_sentinel): Likewise.
+        (sequential_multiway_merge): Added checks for total length 0.
+        (parallel_multiway_merge): Skip empty sequences.
+        (multiway_merge, all variants):
+        Remove temporary variable, return directly.
+        (stable_multiway_merge, all variants): Likewise.
+        (multiway_merge_sentinels, all variants):  Likewise.
+        (stable_multiway_merge_sentinels, all variants): Likewise.
+        * include/parallel/multiseq_selection.h
+        (multiseq_partition): More detailed assertions.
+
 2008-04-21  Ralf Wildenhues  <Ralf.Wildenhues@gmx.de>
 
 	* acinclude.m4 (GLIBCXX_CHECK_SETRLIMIT, GLIBCXX_ENABLE_C99)

libstdc++-v3/include/parallel/multiseq_selection.h

@@ -151,16 +151,24 @@ namespace __gnu_parallel
                       nmax, n, r;
 
       for (int i = 0; i < m; i++)
+        {
           N += std::distance(begin_seqs[i].first, begin_seqs[i].second);
+          _GLIBCXX_PARALLEL_ASSERT(
+            std::distance(begin_seqs[i].first, begin_seqs[i].second) > 0);
+        }
 
       if (rank == N)
         {
           for (int i = 0; i < m; i++)
             begin_offsets[i] = begin_seqs[i].second; // Very end.
           // Return m - 1;
+          return;
         }
 
-      _GLIBCXX_PARALLEL_ASSERT(m != 0 && N != 0 && rank >= 0 && rank < N);
+      _GLIBCXX_PARALLEL_ASSERT(m != 0);
+      _GLIBCXX_PARALLEL_ASSERT(N != 0);
+      _GLIBCXX_PARALLEL_ASSERT(rank >= 0);
+      _GLIBCXX_PARALLEL_ASSERT(rank < N);
 
       difference_type* ns = new difference_type[m];
       difference_type* a = new difference_type[m];