[Rd] Memcheck: Invalid read of size 4

[Christophe Genolini]

Thanks a lot. Your correction works just fine.

Any idea of what goes wrong for the line 151, which is

    int *clusterAffectation2=malloc(*nbInd * sizeof(int));                      // lines 151





> On 19 Mar 2014, at 22:58 , Christophe Genolini <cgenolin at u-paris10.fr> wrote:
>
>> Hi the list,
>>
>> One of my package has a memory issue that I do not manage to understand. The Memtest notes is here:
>> <http://www.stats.ox.ac.uk/pub/bdr/memtests/valgrind/kml-Ex.Rout>
>>
>> Here is the message that I get from Memtest
>>
>> --- 8< ----------------
>> ~ Fast KmL ~
>> ==27283== Invalid read of size 4
>> ==27283==    at 0x10C5DF28: kml1 (kml.c:183)
>> ...
>> ==27283==    by 0x10C5DE4F: kml1 (kml.c:151)
>> ...
>> ==27283==    at 0x10C5DF90: kml1 (kml.c:198)
>> --- 8< ----------------
>>
>>
>> Here is the function kml1 from the file kml.c (I add some comments to tag the lines 151, 183 and 198)
>>
>> --- 8< ----------------
>> void kml1(double *traj, int *nbInd, int *nbTime, int *nbClusters, int *maxIt, int *clusterAffectation1, int *convergenceTime){
>>
>>     int i=0,iter=0;
>>     int *clusterAffectation2=malloc(*nbInd * sizeof(int));                      // lines 151
>>     double *trajMean=malloc(*nbClusters * *nbTime * sizeof(double));
>>
>>     for(i = 0; i < *nbClusters * *nbTime; i++){trajMean[i] = 0.0;};
>>     for(i = 0; i < *nbInd; i++){clusterAffectation2[i] = 0;};
>>
>>     for(iter = 0; iter < *maxIt; iter+=2){
>> 	calculMean(traj,nbInd,nbTime,clusterAffectation1,nbClusters,trajMean);
>>        	affecteIndiv(traj,nbInd,nbTime,trajMean,nbClusters,clusterAffectation2);
>>
>> 	i = 0;
>> 	while(clusterAffectation1[i]==clusterAffectation2[i] && i <*nbInd){i++;}; // lines 183
>> 	if(i == *nbInd){
>> 	    *convergenceTime = iter + 1;
>> 	    break;
>> 	}else{};
>>
>> 	calculMean(traj,nbInd,nbTime,clusterAffectation2,nbClusters,trajMean);
>> 	affecteIndiv(traj,nbInd,nbTime,trajMean,nbClusters,clusterAffectation1);
>>
>> 	i = 0;
>> 	while(clusterAffectation1[i]==clusterAffectation2[i] && i<*nbInd){i++;}; // lines 198
>> 	if(i == *nbInd){
>> 	    *convergenceTime = iter + 2;
>>       	    break;
>> 	}else{};
>>     }
>> }
>> --- 8< ----------------
>>
>> Do you know what is wrong in my C code?
> Yes. You need to reverse operands of &&. Otherwise you'll be indexing with i==*nbind before finding that (i < *nbind) is false.
>
>> Thanks
>>
>> Christophe
>>
>> -- 
>> Christophe Genolini
>> Maître de conférences en bio-statistique
>> Université Paris Ouest Nanterre La Défense
>> INSERM UMR 1027
>>
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel


-- 
Christophe Genolini
Maître de conférences en bio-statistique
Université Paris Ouest Nanterre La Défense
INSERM UMR 1027