Search code examples
cautoconfautomake

AC_SEARCH_LIBS on a static library that itself has dependencies?

How do I use the Autoconf AC_SEARCH_LIBS macro in configure.ac in order to search for a static library when that library itself depends on other libraries?

Consider this example.

I am writing a set of high-level wrapping functions for the plotting library PLplot and putting my object files into a static library, libpsm.a, that gets installed by Automake into /usr/local/lib. The PLplot objects it depdends on are not in the library. Next, I have another program which I intend to use my library directly, and the PLplot library indirectly. In the configure.ac for that program I have this. The sm_device function is one that is in my library. 

AC_SEARCH_LIBS([sm_device],[psm],[],[
  AC_MSG_ERROR([unable to find the sm_device function])
])

The problem I am experiencing is that this test fails because the AC_SEARCH_LIBS macro tries to compile a small test program that links to the search library, libpsm.a and call the function sm_device, but that will fail because the test program does not also link to the PLplot libraries that it indirectly depends on.

  1. How is this done given this configuration, where my library is a static library, it doesn't include the PLplot libraries, and it doesn't use PLplot's shared object libraries?
  2. Should I switch to shared libraries? I.e., use PLplot's share libs and perhaps make my library a shared lib? Would that be necessary, or just recommended?
  3. What is the "correct" way to solve this problem?
Solution

  • The 5th argument to AC_SEARCH_LIBS is for listing the dependent libraries:

    AC_SEARCH_LIBS (function, search-libs, [action-if-found],
    [action-if-not-found], [other-libraries])

    The other-libraries argument should be a space separated list of flags that will be passed to the linker during tests: eg -lm -lfoo -lbar

    See http://www.gnu.org/software/autoconf/manual/autoconf-2.69/html_node/Libraries.html#Libraries