Why -D_THREAD_SAFE?

[Craig Rodrigues]

Hi,

In /usr/ports/Mk/bsd.port.mk there is this:

.if ${OSVERSION} < 500016
PTHREAD_CFLAGS= -D_THREAD_SAFE
PTHREAD_LIBS=           -pthread
.else
PTHREAD_CFLAGS= -D_THREAD_SAFE
PTHREAD_LIBS=           -lc_r
.endif


I understand that -pthread has been deprecated 
in gcc in -CURRENT.  Why is -D_THREAD_SAFE
needed?

I can't find it in any header files under /usr/include .

I am using -CURRENT.

-- 
Craig Rodrigues        
http://crodrigues.org
rodrigc at crodrigues.org