libidn-1.23 bug in lib/Makefile cross-building for Windows

[René Berber]

Hello,

I'm trying to cross-build libidn version 1.23, and I seem to have run
into a bug.

In file lib/Makefile there is:

am__append_5 = -Wl,--output-def,libidn-$(DLL_VERSION).def
...
libidn_la_LDFLAGS = -version-info \
        $(LT_CURRENT):$(LT_REVISION):$(LT_AGE) -no-undefined \
        $(am__append_3) $(am__append_4) $(am__append_5)
...
defexec_DATA = libidn-$(DLL_VERSION).def
...
install-defexecDATA: $(defexec_DATA)
        ...

The last rule depends on the .def file, but libidn_la_LDFLAGS  is not
used, so the .def file is not built.

Where am I seeing this?  Gentoo Linux, using crossdev with a
x86_64-w64-mingw32 target.
-- 
René Berber