Re: [uml-devel] Re: pthreads?

[Geert U. <ge...@li...>]

On Thu, 2 Oct 2003, Jan Hudec wrote:

> On Thu, Oct 02, 2003 at 12:03:10 +0200, Geert Uytterhoeven wrote:
> > Hence _your_ simple application doesn't need libpthread.
> 
> Hence NEITHER OF GTK, GDK, GLIB, GMODULE, GOBJECT, PANGO, ATK, X11 NEED
> libpthread!
> 
> > | gcc -Wl,-T,arch/um/uml.lds.s -static -Wl,--wrap,malloc -Wl,--wrap,free -Wl, --wrap,calloc  -o linux arch/um/main.o vmlinux -L/usr/lib -lutil -L/usr/X11R6/li b -lgtk -lgdk -lX11 -lXi -lXext -lglib -lgmodule -ldl -lm -lgthread
> 
> However if you link with gthread, you need pthread.
> So: a) Please don't blame it on X11.

What about this:

| /usr/X11R6/lib/libX11.a(XlibInt.o)(.text+0x74c): In function `_XEventsQueued':
| : undefined reference to `pthread_equal'
| /usr/X11R6/lib/libX11.a(XlibInt.o)(.text+0x766): In function `_XEventsQueued':
| : undefined reference to `pthread_equal'
| /usr/X11R6/lib/libX11.a(XlibInt.o)(.text+0x781): In function `_XEventsQueued':
| : undefined reference to `pthread_equal'
| /usr/X11R6/lib/libX11.a(XlibInt.o)(.text+0x79a): In function `_XEventsQueued':
| : undefined reference to `pthread_equal'
| /usr/X11R6/lib/libX11.a(XlibInt.o)(.text+0x7b7): In function `_XEventsQueued':
| : undefined reference to `pthread_equal'
| /usr/X11R6/lib/libX11.a(XlibInt.o)(.text+0xafc): more undefined references to `pthread_equal' follow

Some investigation shows that libX11 needs pthread_equal() when linked
statically, while it doesn't need it when linked dynamically.

>     b) Don't link against gthread unless you need them.
>     b.1) If you only call Gtk stuff in one thread, you don't need them.
>     b.2) If you call Gtk stuff from more than one thread, you can still
> 	 provide gthread library with custom locking and get rid of
> 	 pthread.

I tried that, providing my own implementation for pthread_equal().
However, it hangs during gtk_init(). Since this doesn't happen within my
stand-alone GTK test app, it must be some interaction between UML and GTK...

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@li...

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds