Add slightly more explicit warning about running "make clean" when
changing the --with-thread option. I'm doubtful this will help
though...
diff --git a/README b/README
index 33ca859..895b84e 100644
--- a/README
+++ b/README
@@ -559,7 +559,8 @@
because there are run-time penalties when support for them is
compiled in even if you don't use them.) IMPORTANT: run "make
clean" after changing (either enabling or disabling) this
- option! Note: for DEC Unix use --with-dec-threads instead.
+ option, or you will get link errors! Note: for DEC Unix use
+ --with-dec-threads instead.
--with-sgi-dl: On SGI IRIX 4, dynamic loading of extension modules is
supported by the "dl" library by Jack Jansen, which is