[384] in Pthreads mailing list archive
Bug report: pthreads-1_60_beta5.
daemon@ATHENA.MIT.EDU (drh@tobit.vnet.net)
Thu Aug 15 09:46:19 1996
From: drh@tobit.vnet.net
Date: Thu, 15 Aug 96 09:12 EDT
To: proven@MIT.EDU, pthreads@MIT.EDU
The program below will normally core-dump within about 60 seconds on
a P90 (with the FDIV bug) running Linux 1.2.13 and pthreads-1_60_beta5.
GDB tells me the error is in the file stdlib/strtod.c. The Balloc()
routine in this file appears to use static data (freelist[]) but is not
locked. I'm working on a fix now, but do not have one available at
this writing.
Example code that exercises the problem follows. The test program calls
sprintf() with a floating-point convertion repeatedly in many threads.
I normally run the test program with an argument of about 50.
/*
** A program demonstrate a problem with floating point to ASCII
** conversions in the standard library accompanying Provenzano pthreads,
*/
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
/*
** Every thread begins execution with in the following function
*/
void *DoThread(void *clientData){
int i;
double v = 1.0009999999999999999999999;
char zBuf[100];
for(i=0; i<1000000; i++){
sprintf(zBuf,"%3.1f",v);
}
pthread_exit(0);
}
/*
** Start up N threads, each running the same job.
*/
void main(int argc, char **argv){
int i,N;
if( argc!=2 ){
fprintf(stderr,"Usage: %s num-threads\n",*argv);
exit(1);
}
N = atoi(argv[1]);
for(i=1; i<N; i++){
pthread_t threadId;
if( pthread_create(&threadId,0,DoThread,0)<0 ){
perror("Can't start a new thread");
}else{
pthread_detach(threadId);
}
}
if( N>0 ){
DoThread(0);
}
}
Thanks for all your help.
---------------
D. Richard Hipp drh@tobit.vnet.net
