Experimental Physics and
Industrial Control System

Mark Rivers via Core-talk <core-talk at aps.anl.gov> · Thu, 16 Jul 2020 12:15:05 +0000

Hi Dirk,


I believe I have already fixed the problem you are seeing.  It was an error in the Makefile.  It should have been linking with EPICS_BASE_IOC_LIBS, unless EPICS_LIBCOM_ONLY was YES.  This is the diff of the master branch from R4-39 for the Makefile.

corvette:asyn/asynPortDriver/unittest>git diff R4-39 Makefile

diff --git a/asyn/asynPortDriver/unittest/Makefile b/asyn/asynPortDriver/unittest/Makefile
index 7618c68..a8a257f 100644
--- a/asyn/asynPortDriver/unittest/Makefile
+++ b/asyn/asynPortDriver/unittest/Makefile
@@ -10,8 +10,17 @@ TOP=../../..

 include $(TOP)/configure/CONFIG

+USR_CFLAGS += -DUSE_TYPED_RSET -DUSE_TYPED_DSET -DUSE_TYPED_DRVET
+USR_CXXFLAGS += -DUSE_TYPED_RSET -DUSE_TYPED_DSET -DUSE_TYPED_DRVET
+
 PROD_LIBS += asyn
-PROD_LIBS += Com
+ifeq ($(EPICS_LIBCOM_ONLY),YES)
+  PROD_LIBS += Com
+  USR_CXXFLAGS += -DEPICS_LIBCOM_ONLY
+  USR_CFLAGS   += -DEPICS_LIBCOM_ONLY
+else
+  PROD_LIBS += $(EPICS_BASE_IOC_LIBS)
+endif

 #Tests for the parameters
 #TESTPROD_HOST += ParamValTest



Mark



________________________________
From: Core-talk <core-talk-bounces at aps.anl.gov> on behalf of Zimoch Dirk (PSI) via Core-talk <core-talk at aps.anl.gov>
Sent: Thursday, July 16, 2020 4:51 AM
To: 'core-talk at aps.anl.gov'
Subject: EPICS linker problem

Hello folks,

Today I found that some Linux (cross) architectures (using gcc 4.4.2, 4.7.2) require an additional linker flag: -Wl,-rpath-link in addition to -L and -Wl,-rpath. I noticed when compiling asyn.
It worked for me to change in <BASE>/configure/os/CONFIG.Common.linuxCommon
PRODDIR_RPATH_LDFLAGS_YES = $(PROD_DEPLIB_DIRS:%=-Wl,-rpath,%)
to
PRODDIR_RPATH_LDFLAGS_YES = $(PROD_DEPLIB_DIRS:%=-Wl,-rpath,%) $(PROD_DEPLIB_DIRS:%=-Wl,-rpath-link,%)
(Maybe the same should be done for SHRLIBDIR_RPATH_LDFLAGS_YES.)

Why this? Some linkers do not use -L for indirectly linked libs. E.g. libA.so depends on libB.so and the program is linked with -lA but not with -lB, then some linkers require that B is found in -rpath-link and do not consider -L or -rpath for it. (Maybe the other linkers where it works do not even care about B?)

In asyn this is the case for test code which links with -lasyn -lCom only. But libasyn.so had been linked with -ldbRecStd -ldbCore -lca -lCom and the linker refuses to use those other libraries from -L<EPICS_BASE_LIBDIR> or -Wl,-rpath<EPICS_BASE_LIBDIR>.

/opt/eldk-5.3/powerpc-4xx/sysroots/i686-eldk-linux/usr/bin/ppc440e-linux/powerpc-linux-g++  -D_GNU_SOURCE -D_DEFAULT_SOURCE           -m32 -mcpu=440fp -mhard-float --sysroot=/opt/eldk-5.3/powerpc-4xx/sysroots/ppc440e-linux  -DUNIX  -Dlinux  -fno-strict-aliasing    -O3 -g -g   -Wall             -I. -I../O.Common -I. -I. -I.. -I../../../../include/compiler/gcc -I../../../../include/os/Linux -I../../../../include          -I/usr/local/epics/base-7.0.4.1/include/compiler/gcc -I/usr/local/epics/base-7.0.4.1/include/os/Linux -I/usr/local/epics/base-7.0.4.1/include        -c ../asynPortDriverTest.cpp
/opt/eldk-5.3/powerpc-4xx/sysroots/i686-eldk-linux/usr/bin/ppc440e-linux/powerpc-linux-g++ -o asynPortDriverTest  -L/afs/psi.ch/group/8211/dirk/git/DRV/asyn/lib/eldk53-ppc4xxFP -L/usr/local/epics/base-7.0.4.1/lib/eldk53-ppc4xxFP -Wl,-rpath,/afs/psi.ch/group/8211/dirk/git/DRV/asyn/lib/eldk53-ppc4xxFP -Wl,-rpath,/usr/local/epics/base-7.0.4.1/lib/eldk53-ppc4xxFP       --sysroot=/opt/eldk-5.3/powerpc-4xx/sysroots/ppc440e-linux    -rdynamic         asynPortDriverTest.o    -lasyn -lCom
/net/gfa-fs-4/export/cross_tools/eldk-5.3/powerpc-4xx/sysroots/i686-eldk-linux/usr/bin/ppc440e-linux/../../libexec/ppc440e-linux/gcc/powerpc-linux/4.7.2/ld: warning: libdbRecStd.so, needed by /afs/psi.ch/group/8211/dirk/git/DRV/asyn/lib/eldk53-ppc4xxFP/libasyn.so, not found (try using -rpath or -rpath-link)
/net/gfa-fs-4/export/cross_tools/eldk-5.3/powerpc-4xx/sysroots/i686-eldk-linux/usr/bin/ppc440e-linux/../../libexec/ppc440e-linux/gcc/powerpc-linux/4.7.2/ld: warning: libdbCore.so, needed by /afs/psi.ch/group/8211/dirk/git/DRV/asyn/lib/eldk53-ppc4xxFP/libasyn.so, not found (try using -rpath or -rpath-link)
/net/gfa-fs-4/export/cross_tools/eldk-5.3/powerpc-4xx/sysroots/i686-eldk-linux/usr/bin/ppc440e-linux/../../libexec/ppc440e-linux/gcc/powerpc-linux/4.7.2/ld: warning: libca.so, needed by /afs/psi.ch/group/8211/dirk/git/DRV/asyn/lib/eldk53-ppc4xxFP/libasyn.so, not found (try using -rpath or -rpath-link)
/afs/psi.ch/group/8211/dirk/git/DRV/asyn/lib/eldk53-ppc4xxFP/libasyn.so: undefined reference to `scanIoRequest'
[... more undefined reference errors...]

Even though the warning suggests using -rpath or -rpath-link, only -rpath-link actually does the job.

Is there any (old) Linux architecture where adding -rpath-link may cause problems?

Dirk



Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System