Hmmmm. I guess someone forgot to update the online gcc manual. All I see at http://gcc.gnu.org/onlinedocs/gcc/Option-Index.html#Option-Index is pthread: SPARC Options pthread: RS/6000 and PowerPC Options pthreads: SPARC Options No mention of Irix or Linux. -----Original Message----- From: Ian Lance Taylor [mailto:iant@xxxxxxxxxx] Sent: Tuesday, September 22, 2009 12:52 PM To: Tovrea, George W (US SSA) Cc: 'Kai Ruottu'; gcc-help@xxxxxxxxxxx Subject: Re: GCC 4.4.0, mips-sgi-irix6.5 and pthread - MORE "Tovrea, George W (US SSA)" <george.tovrea@xxxxxxxxxxxxxx> writes: > The -pthread option is only valid for Solaris. That is not correct. The -pthreads (note final 's') option is only valid for Solaris. The -pthread option is valid on many systems, including Irix and GNU/Linux. Ian