[Xcb] x11 static compile fail

[Rafi Rubin]

Compiling a static x11 program fails using the output of:
pkg-config --static --libs x11

The problem appears to be -lpthread shows up only before -lxcb. There's
something a bit odd in the pkg-config files. x11.pc has pthread in
Libs.private, and xcb has pthread-stubs in Requires.private. However
pthread-stubs isn't actually adding the -l flag to the output, and the
resulting ordering breaks my build.

So, which package should be correct: x11 or xcb? Should the
pthread-stubs have -lpthread in Libs.private?


My versions:
ibxcb1-dev 1.11.1-1
libx11-dev 2:1.6.3-1
libpthread-stubs0-dev 0.3-4


Rafi

[Uli Schlachter]

Post by Rafi Rubin
pkg-config --static --libs x11
The problem appears to be -lpthread shows up only before -lxcb. There's
something a bit odd in the pkg-config files. x11.pc has pthread in
Libs.private, and xcb has pthread-stubs in Requires.private. However
pthread-stubs isn't actually adding the -l flag to the output, and the
resulting ordering breaks my build.
So, which package should be correct: x11 or xcb? Should the
pthread-stubs have -lpthread in Libs.private?
ibxcb1-dev 1.11.1-1
libx11-dev 2:1.6.3-1
libpthread-stubs0-dev 0.3-4

I'm on debian testing and my
/usr/lib/x86_64-linux-gnu/pkgconfig/pthread-stubs.pc contains "Libs:". If I
download pthread-stubs and hack it with the following patch, then your static
build works for me.

diff --git a/configure.ac b/configure.ac
index ef300ad..af00a14 100644
--- a/configure.ac
+++ b/configure.ac
@@ -38,7 +38,6 @@ m4_divert_pop([KILL])

dnl Check which functions we need to provide aliases for.
PKG_CONFIG_LIBS=
-AC_CHECK_FUNCS(funclist, [], [PKG_CONFIG_LIBS='-L${libdir} -lpthread-stubs'])

AC_SUBST([PKG_CONFIG_LIBS])
AM_CONDITIONAL(BUILD_LIB, test "x$PKG_CONFIG_LIBS" != x)



And indeed:

$ nm --dynamic /lib/x86_64-linux-gnu/libc.so.6 | grep pthread_cond_signal
00000000000f50d0 T pthread_cond_signal
000000000011ee60 T pthread_cond_signal

So why does this fail static compilation? I looked for libc.a and ran:

$ ar x /usr/lib/x86_64-linux-gnu/libc.a
$ for x in *.o ; do readelf -a $x ; done | grep pthread_cond_signal
$

So the dynamic version of libc provides the pthread symbols (and thus
pthread-stubs figures out it is not needed) while the static version does not.

Report a bug against libc on debian? What do others think?

Cheers,
Uli