Re: AC_CHECK_LIB: Library is found on build host but is not on a target host

[Eric Blake]

On 08/23/2010 11:56 AM, Sergio Belkin wrote:
> Hi,
>
> I've autoconfiscated an open source project. I don't using still
> automake, only I am using autoconf. So I've created an confugure.ac as
> follows:
>
> AC_PREREQ([2.65])
> AC_INIT([UpTools],[8.4],address@hidden)
> AM_INIT_AUTOMAKE([foreign -Wall -Werror dist-bzip2])

Umm - this line says you're using automake.

> AC_CONFIG_SRCDIR([UpConf.cc])
> AC_CONFIG_HEADERS([config.h])
> AC_PROG_CXX
> AC_PROG_CC
> AC_LANG([C++])
> AC_PROG_RANLIB
>
>
> AC_CHECK_LIB([ssl], [main],[SSL=-lssl],echo "Error: Required library
> ssl not found. Install openssl development package and try again"&&
> exit 1 )

Get in the habit of using proper m4 quoting.  Also, use AC_MSG_ERROR 
instead of hand-rolling your own version (since your version forgot to 
document anything in config.log):

AC_CHECK_LIB([ssl], [main],[SSL=-lssl],
  [AC_MSG_ERROR(["Error: Required library ssl not found. Install 
openssl development package and try again"])])

Another thing - these days, it is generally better to use AC_SEARCH_LIBS 
than AC_CHECK_LIB, since there are some platforms that provide functions 
in libc and thus don't require any external libraries to be linked in.

> if test -e /usr/lib64/libresolv.a

Ouch - that is doomed to failure.  It is better to check whether linking 
with -lresolv can succeed, than it is to assume that existence of a 
hard-coded location implies that the library is available.

> I've build that on Mandriva 2010.1 and it worked fine. It compiles
> with no problems. But it's failing to find mysql libraries on a Fedora
> 9 system even those libraries are installed:

I didn't see any mention of mysql in your sample configure.ac, nor any 
macro call that would explain why you are getting this message:

> checking for mysql_get_parameters in -lmysqlclient... no
> Error: Required library mysqlclient not found. Install it and try again

Are you sure you pasted the right file?

--
Eric Blake   address@hidden    +1-801-349-2682
Libvirt virtualization library http://libvirt.org