[PATCH] libmount/buildsys: move SELINUX_LIBS to LDFLAGS

[PATCH] libmount/buildsys: move SELINUX_LIBS to LDFLAGS

[Andreas Henriksson]

According to a bug report filed in the Debian bug tracking system
an unknown version of the package failed to cross-build because of
the -lfoo flags for SELinux being placed in LIBADD rather then LDFLAGS.
The build system still looks similar in this regard so it's possible
the problem still remains and hopefully this change should make things
more correct even if I still don't know if it solves the entire problem.

Reported-by: YunQiang Su <wzssyqa@gmail.com>
Addresses-Debian-Bug: #721431
Signed-off-by: Andreas Henriksson <andreas@fatal.se>
---
 libmount/src/Makemodule.am | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libmount/src/Makemodule.am b/libmount/src/Makemodule.am
index 54ab51d..afe5cfa 100644
--- a/libmount/src/Makemodule.am
+++ b/libmount/src/Makemodule.am
@@ -30,7 +30,7 @@ libmount_la_SOURCES = \
 
 nodist_libmount_la_SOURCES = libmount/src/mountP.h
 
-libmount_la_LIBADD = libcommon.la libblkid.la $(SELINUX_LIBS)
+libmount_la_LIBADD = libcommon.la libblkid.la
 
 libmount_la_CFLAGS = \
 	$(SOLIB_CFLAGS) \
@@ -46,6 +46,7 @@ libmount_la_DEPENDENCIES = \
 
 libmount_la_LDFLAGS = \
 	$(SOLIB_LDFLAGS) \
+	$(SELINUX_LIBS) \
 	-Wl,--version-script=$(top_srcdir)/libmount/src/libmount.sym \
 	-version-info $(LIBMOUNT_VERSION_INFO)
 
-- 
2.0.1

Re: [PATCH] libmount/buildsys: move SELINUX_LIBS to LDFLAGS

[Mike Frysinger]

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On Sat 02 Aug 2014 22:11:01 Andreas Henriksson wrote:
> According to a bug report filed in the Debian bug tracking system
> an unknown version of the package failed to cross-build because of
> the -lfoo flags for SELinux being placed in LIBADD rather then LDFLAGS.
> The build system still looks similar in this regard so it's possible
> the problem still remains and hopefully this change should make things
> more correct even if I still don't know if it solves the entire problem.

please post the full details here.  linkage (like -lselinux) are not ldflags.
-mike

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Re: [PATCH] libmount/buildsys: move SELINUX_LIBS to LDFLAGS

[Andreas Henriksson]

Hello Mike Frysinger!

On Sun, Aug 03, 2014 at 09:34:25AM -0400, Mike Frysinger wrote:
[...]
> please post the full details here. 

I have no more details then those found in
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=721431

Maybe YunQiang Su can help out and provide some additional information
here....

> linkage (like -lselinux) are not ldflags.

Works for me, but likely I got LIBADD/LDFLAGS/LDADD wrong (again).

Regards,
Andreas Henriksson

Re: [PATCH] libmount/buildsys: move SELINUX_LIBS to LDFLAGS

[Mike Frysinger]

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On Sun 03 Aug 2014 22:23:09 Andreas Henriksson wrote:
> Hello Mike Frysinger!
> 
> On Sun, Aug 03, 2014 at 09:34:25AM -0400, Mike Frysinger wrote:
> [...]
> 
> > please post the full details here.
> 
> I have no more details then those found in
> https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=721431

well, that thing has barely 6 lines (and even then requires some esoteric 
knowledge from the reader), so you could have just pasted it here :p
------
In libmount/src/Makefile.am

libmount_la_LIBADD = $(ul_libblkid_la) $(SELINUX_LIBS)

libmount_la_DEPENDENCIES = $(libmount_la_LIBADD) libmount.sym libmount.h.in

While $(SELINUX_LIBS) is '-lselinux -lsepol'

They are not files or makefile tag, so cannot build-depends on.
------

the problem is that libmount_la_DEPENDENCIES shows up in the Makefile like:
libmount.la: ... $(libmount_la_DEPENDENCIES) ...

which means make evaluates it like so:
libmount.la: ... -lselinux -lsepol ...

which triggers the builtin library path searching of make itself:
https://www.gnu.org/software/make/manual/make.html#Libraries_002fSearch

which means it'll rewrite -lselinux into /usr/lib/libselinux.so (if it can 
find it) which is bad for multilib and cross-compiling.

the easy answer is to not add LIBADD to DEPENDENCIES.  which has been done 
already -- see dbf7043ea1d090d283cfd36280bb14189d8e35b1.

> > linkage (like -lselinux) are not ldflags.
> 
> Works for me, but likely I got LIBADD/LDFLAGS/LDADD wrong (again).

it often works in the common case, but the edges break down.  we know putting 
-lflags into LDFLAGS is such a scenario :).
-mike

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Re: [PATCH] libmount/buildsys: move SELINUX_LIBS to LDFLAGS

[Andreas Henriksson]

Version: 2.25-1

Hello Mike!

Thank you very much for the followup and for identifying the relevant
commit for me!
(BCCing the debian bug tracking system to close the bug report...)

On Mon, Aug 04, 2014 at 03:40:56AM -0400, Mike Frysinger wrote:
[...]
> the problem is that libmount_la_DEPENDENCIES shows up in the Makefile like:
> libmount.la: ... $(libmount_la_DEPENDENCIES) ...
> 
> which means make evaluates it like so:
> libmount.la: ... -lselinux -lsepol ...
> 
> which triggers the builtin library path searching of make itself:
> https://www.gnu.org/software/make/manual/make.html#Libraries_002fSearch
> 
> which means it'll rewrite -lselinux into /usr/lib/libselinux.so (if it can 
> find it) which is bad for multilib and cross-compiling.
> 
> the easy answer is to not add LIBADD to DEPENDENCIES.  which has been done 
> already -- see dbf7043ea1d090d283cfd36280bb14189d8e35b1.
> 
[...]


Regards,
Andreas Henriksson