In my windows branch, I use link_search_path_spec as in:
_LT_TAGDECL([], [link_search_path_spec], [1],
[Flag to add a directory to the linker search path])
Then, somewhere in the "-L*" case of argument processing in func_mode_link.
if test -n "$link_search_path_spec"; then
this_deplib="$link_search_path_spec$dir"
else
this_deplib="-L$dir"
fi
where all cases of the existing "-L$dir" is replaced by
"$this_deplib". Note also that there is an explicit case for
"-LIBPATH:*" so that -LIBPATH can be used in user-defined environment
variables for example. My windows branch seems to work ok for the PGI
and Intel compilers on windows with a couple exceptions:
* running executables (e.g. test programs for the testsuite) that use DLLs.
* building DLLs with version information.