Ostringstream 10; hangs when compiled and build with -mt option.

Question

I've written a very simple program to test the use of the stl class ostringstream. The program write an integer to the ostringstream object. In a multithreaded environment (compiled and build with the -mt option), that operation hangs and never returns, whilst it works fine if the program is compiled and build without the -mt option.
Here is the program :
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sstream>
int main() {
std::ostringstream buffer;
printf("before writing integer to ostringstream\n"); fflush(stdout);
buffer<< 10;
printf("after writing integer to ostringstream.\n"); fflush(stdout);
printf("exiting.\n"); fflush(stdout);
return 0;
Compilation and build :
CC -mt test.cpp -o test
Do you any idea why the program hangs at buffer << 10; in a multithreaded environment ?
(I have tried to write a string instead of a integer, then it works).
Thanks a lot

Answer 1

Hi, I've tried your code with Solaris 7 with Forte Developer 6.2, and it seems to work fine. I get the following output:
before writing integer to ostringstream
after writing integer to ostringstream.
exiting.
My compiler version is:
CC: Sun WorkShop 6 update 2 C++ 5.3 Patch 111685-03 2001/10/19
-Moazam