2007-11-14 Johannes Singler <singler@ira.uka.de>

      * include/parallel/multiway_merge.h: More robust finding of an
        arbitrary existing element inside the input sequences.
      * include/bits/stl_algo.h: Fix typo to actually call appropriate
        sequential version.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@130183 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index d0683a1..466c8f1 100644 (file)
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,11 @@
+2007-11-14  Johannes Singler  <singler@ira.uka.de>
+
+      * include/parallel/multiway_merge.h: More robust finding of an
+        arbitrary existing element inside the input sequences.
+      * include/bits/stl_algo.h: Fix typo to actually call appropriate
+        sequential version.
+
+
 2007-11-13  Benjamin Kosnik  <bkoz@redhat.com>
 
        * docs/html/documentation.html: First pass at unified table of contents.

diff --git a/libstdc++-v3/include/bits/stl_algo.h b/libstdc++-v3/include/bits/stl_algo.h
index 154e225..3765dc0 100644 (file)
--- a/libstdc++-v3/include/bits/stl_algo.h
+++ b/libstdc++-v3/include/bits/stl_algo.h
@@ -2028,7 +2028,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
        {
          if (__depth_limit == 0)
            {
-             _GLIBCXX_STD_P:partial_sort(__first, __last, __last);
+             _GLIBCXX_STD_P::partial_sort(__first, __last, __last);
              return;
            }
          --__depth_limit;

diff --git a/libstdc++-v3/include/parallel/multiway_merge.h b/libstdc++-v3/include/parallel/multiway_merge.h
index c7d317a..2e3be7c 100644 (file)
--- a/libstdc++-v3/include/parallel/multiway_merge.h
+++ b/libstdc++-v3/include/parallel/multiway_merge.h
@@ -900,25 +900,34 @@ namespace __gnu_parallel
     difference_type total_length = 0;
 
     // Default value for potentially non-default-constructible types.
-    value_type* defaultcons = NULL; 
+    value_type* arbitrary_element = NULL;
+
     for (int t = 0; t < k; t++)
       {
-       if (stable)
-         {
-           if (seqs_begin[t].first == seqs_begin[t].second)
-             lt.insert_start_stable(*defaultcons, t, true);
-           else
-             lt.insert_start_stable(*seqs_begin[t].first, t, false);
-         }
-       else
-         {
-           if (seqs_begin[t].first == seqs_begin[t].second)
-             lt.insert_start(*defaultcons, t, true);
-           else
-             lt.insert_start(*seqs_begin[t].first, t, false);
-         }
+        if(arbitrary_element == NULL && LENGTH(seqs_begin[t]) > 0)
+          arbitrary_element = &(*seqs_begin[t].first);
+        total_length += LENGTH(seqs_begin[t]);
+      }
 
-       total_length += LENGTH(seqs_begin[t]);
+    if(total_length == 0)
+      return target;
+
+    for (int t = 0; t < k; t++)
+      {
+        if (stable)
+          {
+            if (seqs_begin[t].first == seqs_begin[t].second)
+              lt.insert_start_stable(*arbitrary_element, t, true);
+            else
+              lt.insert_start_stable(*seqs_begin[t].first, t, false);
+          }
+        else
+          {
+            if (seqs_begin[t].first == seqs_begin[t].second)
+              lt.insert_start(*arbitrary_element, t, true);
+            else
+              lt.insert_start(*seqs_begin[t].first, t, false);
+          }
       }
 
     if (stable)
@@ -941,7 +950,7 @@ namespace __gnu_parallel
 
            // Feed.
            if (seqs_begin[source].first == seqs_begin[source].second)
-             lt.delete_min_insert_stable(*defaultcons, true);
+             lt.delete_min_insert_stable(*arbitrary_element, true);
            else
              // Replace from same source.
              lt.delete_min_insert_stable(*seqs_begin[source].first, false);
@@ -959,7 +968,7 @@ namespace __gnu_parallel
 
            // Feed.
            if (seqs_begin[source].first == seqs_begin[source].second)
-             lt.delete_min_insert(*defaultcons, true);
+             lt.delete_min_insert(*arbitrary_element, true);
            else
              // Replace from same source.
              lt.delete_min_insert(*seqs_begin[source].first, false);