automake program libtool wrapper linking

Question

Am stumped on an automake link. Even after pouring over the manuals for hours and searching online it is probably a misunderstanding of autotools.

I have one .la library made by libtool, one .dylib shared library and am creating a program. The .la is linked to the .dylib and the program uses the .la.

Makefile.am for the .la library

lib_LTLIBRARIES = libA.la
libA_la_LDFLAGS = ${AM_LDFLAGS} -no-undefined
libA_la_LIBADD = $(LIBM) -Ldir/to/ -lB
libA_la_CPPFLAGS = ${AM_CPPFLAGS}

Makefile.am for program with libtool wrapper

noinst_PROGRAMS = test
test_SOURCES = test_source.c
test_LDADD = libA.la -Ldir/to/ -lB

libA.la is created and links to B.dylib but the test program "wrapper" created by automake is exporting DYLD_LIBRARY_PATH to find libA.la while not linking to B.dylib. Giving the error

dyld: Library not loaded: ./B.dylib
  Referenced from: /dir/to/test/.libs/test
  Reason: image not found
Trace/BPT trap: 5

Some things that I have tried are adding -Ldir/to/ -lB to test_LDFLAGS in addition to already being added in test_LDADD. And have tried setting test_LDFLAGS = -rpath -Ldir/to in the hopes that setting the runtime search path to the directory where B.dylib is would help.

If I manually export DYLD_LIBRARY_PATH to include /dir/to/B.dylib then the test program is able to run but I'm looking to have autotools take care of this rather than requiring someone to export a path before being able to run it.

umläute umläute · Accepted Answer · 2015-10-06T19:41:12

libB.dylib includes an rpath that gets copied into your binary and that is used to resolve -lB at runtime.

And it seems that this rpath is not /path/to, so libB.dylib cannot be resolved by the runtime linker. The reasons why it works for libA.la is that libtools knows that the rpath in libA.dylib is wrong anyhow (as you haven't done a make install) and so it needs to be set manually.

The only way around this that i have found is to use install_name_tool to fix the stored rpath in the resulting binary. (that is: I don't think that libtool will do this for you, as it contradicts the intended use of libB.dylib - as declared in its rpath)

automake program libtool wrapper linking

2 Answers