Using AC_LIB_HAVE_LINKFLAGS with non standard named libraries generates "non-POSIX" automake error?

[Johan Persson]

I've stumbled on on an "stupid" issue I've never had to deal with before
and I can't seem to get around it (could also be that I'm getting
tired...) 

In my configure.ac I'm using a number of standard
AC_LIB_HAVE_LINKFLAGS() calls to allow the end user to configure the
library locations. This works as expected. 

However one of the libraries I need to configure is named
"libusb-1.0.so" but if I use "usb-1.0" as the library name in the call
to the macro this will the generate an illegal variable name that
automake chokes on. 

SRC/MAKEFILE.AM:19: WARNING: LIBUSB-1.0: NON-POSIX VARIABLE NAME 

Renaming the name of the library is no-solution since I cannot control
3:rd party library installation. 

Have anyone else had to deal with this? (I guess there is a simple
solution that I just fail to see but no matter of what more and more
bizarre quoting I tried with I cannot get automake to accept the name) 

--Johan 

(I'm using autoconf 2.69 / automake 1.12.1)