configure: require pthreads for POSIX builds

This has been an implicit rule for building mesa for a long time. Let's
make it official and just bail out at configure time. This way we can
cleaning up some of our glx code.

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Brian Paul <brianp@vmware.com>

diff --git a/configure.ac b/configure.ac
index 2954f80..a3b0ebd 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -658,6 +658,9 @@ mingw*)
     ;;
 *)
     AX_PTHREAD
+    if test "x$ax_pthread_ok" = xno; then
+        AC_MSG_ERROR([Building mesa on this platform requires pthreads])
+    fi
     ;;
 esac
 dnl AX_PTHREADS leaves PTHREAD_LIBS empty for gcc and sets PTHREAD_CFLAGS