Dear all,
I am testing out the following piece of code using Cygwin.
It works as expected (exits when failing to create a new thread) under
Solaris and Linux.
If the function test is called directly from main without invoking a new
thread, the program works fine.
If test is called as a new thread, then AND there are a lot of threads
created, then Windows pops up a dialog box saying:
The instruction at 0x00401141 referenced memory at 0x8d10c483. The memory
could not be read.
Note: no error (nor seg. fault) is caught inside the Cygwin shell.
Moreover, if you change the number from 30000 to 500, there is no error.
Also, if map<string,string> is replaced by map<int, int>, no error is
generated even if threads are created.
So, the problem only occurs when map<string, string> type is used AND
threads are created. I am thinking if there is a bug with Cygwin, so I am
reporting my finding here.
For those who know the answer, please help! Thank you very much!
Code goes here (complied: g++ mapString.cpp lpthread)
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <map>
#include <string>
using namespace std;
void *test(void *arg) {
// map<string,string> has no problem if called directly.
// This creates memory errors if called by pthread_create.
map<string,string> testString;
string one("1");
testString.insert(map<string,string>::value_type(one, one));
//testString.insert(map<string,string>::value_type(string("1"),
string("1")));
//testString["1"] = "1";
//map<int, int> has no problem regardless of being called from
pthread_create or
//being called directly.
//map<int, int> testInt;
//testInt[1] = 1;
pthread_exit(NULL);
//return 0;
}
int main() {
pthread_t tid[30000];
for (int i=1; i<=30000; i++) {
cout << " i = " << i << endl;
//test(0);
if (pthread_create(&tid[i], 0, test, 0) != 0) {
cerr << i << "-th thread creation error!" << endl;
exit(-1);
}
}
cout << "main: exiting..." << endl;
return 0;
}
Best regards,
Haksun
--
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Bug reporting: http://cygwin.com/bugs.html
Documentation: http://cygwin.com/docs.html
FAQ: http://cygwin.com/faq/
