Index: TH1.cxx
===================================================================
RCS file: /user/cvs/root/hist/src/TH1.cxx,v
retrieving revision 1.330
diff -u -w -r1.330 TH1.cxx
--- TH1.cxx	3 Feb 2007 06:40:25 -0000	1.330
+++ TH1.cxx	4 Feb 2007 20:39:49 -0000
@@ -5057,18 +5057,20 @@
    // Save old bin contents into a new array
    Double_t entries = fEntries;
    Double_t *oldBins = new Double_t[nbins+2];
-   Int_t bin, i;
-   for (bin=0;bin<nbins+2;bin++) oldBins[bin] = GetBinContent(bin);
+
+   for (Int_t bin=0;bin<nbins+2;bin++) oldBins[bin] = GetBinContent(bin);
    Double_t *oldErrors = 0;
    if (fSumw2.fN != 0) {
       oldErrors = new Double_t[nbins+2];
-      for (bin=0;bin<nbins+2;bin++) oldErrors[bin] = GetBinError(bin);
+      for (Int_t bin=0;bin<nbins+2;bin++) oldErrors[bin] = GetBinError(bin);
    }
 
    // create a clone of the old histogram if newname is specified
    TH1 *hnew = this;
+   Bool_t isCloned=kFALSE;
    if ((newname && strlen(newname) > 0) || xbins) {
       hnew = (TH1*)Clone(newname);
+      isCloned=kTRUE;
    }
 
    // change axis specs and rebuild bin contents array::RebinAx
@@ -5117,12 +5119,14 @@
    // copy merged bin contents (ignore under/overflows)
    Int_t oldbin = 1;
    Double_t binContent, binError;
-   for (bin = 1;bin<=newbins;bin++) {
+   for (Int_t bin = 1;bin<=newbins;bin++) {
       binContent = 0;
       binError   = 0;
       Int_t imax = ngroup;
-      for (i=0;i<ngroup;i++) {
-         if (fXaxis.GetBinCenter(oldbin+i) > hnew->GetXaxis()->GetBinUpEdge(bin)) {
+      Float_t binmax = hnew->GetXaxis()->GetBinUpEdge(bin);
+      for (Int_t i=0;i<ngroup;i++) {
+         if( (!isCloned && (oldbin+i > nbins)) || 
+             ( isCloned && (fXaxis.GetBinCenter(oldbin+i) > binmax)) ){
             imax = i;
             break;
          }
@@ -5131,6 +5135,7 @@
       }
       hnew->SetBinContent(bin,binContent);
       if (oldErrors) hnew->SetBinError(bin,TMath::Sqrt(binError));
+
       oldbin += imax;
    }
    hnew->SetBinContent(0,oldBins[0]);