Thanks for the input. The -pthread option is only valid for Solaris. However, I found and fixed the problem. The command line for g++, on SGI, requires -lstdc++. -----Original Message----- From: Kai Ruottu [mailto:kai.ruottu@xxxxxxxxxxx] Sent: Tuesday, September 22, 2009 9:51 AM To: Tovrea, George W (US SSA) Cc: gcc-help@xxxxxxxxxxx Subject: Re: GCC 4.4.0, mips-sgi-irix6.5 and pthread - MORE Tovrea, George W (US SSA) wrote: > This simple program, simple.c, taken from http://www.yolinux.com/TUTORIALS/LinuxTutorialPosixThreads.html > <snip> > Compiled with > gcc -lpthread simple.c > > The sample program compiled with > g++ -lpthread simple.c -L/home/users/tovrea/local/sgi6/lib/gcc/mips-sgi-irix6.5/4.4.0 -L/home/users/tovrea/local/sgi6/lib/gcc/mips-sgi-irix6.5/4.4.0/32 -L/home/users/tovrea/local/sgi6/lib/gcc/mips-sgi-irix6.5/lib32 -L/home/users/tovrea/local/sgi6/lib > > results in a core with backtrace In both compiles the option '-pthread' wasn't used... But the Irix6.x config stuff tells that it has some meaning with Irix6.x like : #undef SUBTARGET_CPP_SPEC #define SUBTARGET_CPP_SPEC "%{pthread:-D_REENTRANT}" So some standard headers may have different definitions with and without this option... > I would greatly appreciate if anyone working with gcc 4.4.0 on mips-sgi-irix6.5 and pthreads would contact me ASAP I don't work with this platform so the previous simple check, compiling with '-pthread', is all I could suggest :(