Link error when using MATHEMATICAL_USE_SYSTEM_LASEM in Cygwin

Hi, I've encountered an error when trying to build mathematical on cygwin while using MATHEMATICAL_USE_SYSTEM_LASEM. The linker complains about undefined references to symbol names with the pattern lsmdom*.

In the build log (see below), the link command does not contain -llasem. It looks like extconf.rb is supposed to add -llasem to the makefile, but that's failing to happen in my environment. I do not understand how to fix that problem.

$ grep -R llasem .
./ext/mathematical/extconf.rb:  $LIBS << ' -llasem'
./ext/mathematical/extconf.rb:    $LIBS << ' -llasem'
./ext/mathematical/lasem/lasem.pc.in:Libs: -L${libdir} -llasem-@LASEM_API_VERSION@

$ grep -R lasem ext/mathematical/Makefile
CPPFLAGS =  -I/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mtex2MML/src -I/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/lasem/src  $(DEFS) $(cppflags)
ORIG_SRCS = cairo_callbacks.c lasem_overrides.c mathematical.c
OBJS = cairo_callbacks.o lasem_overrides.o mathematical.o
HDRS = $(srcdir)/cairo_callbacks.h $(srcdir)/lasem_overrides.h $(srcdir)/mathematical.h

extconf.rb contains this:

if !using_system_lasem?
[...]
else
  if dir_config('lasem').any? || system('dpkg -s liblasem >/dev/null')
    $LIBS << ' -llasem'
  else
    # NOTE: pkg_config implicitly adds right -l argument for the linker.
    pkg_config('liblasem') || pkg_config('lasem')
  end
end

FWIW, I'm following the instructions for setting up the build of a project that uses asciidoctor-mathematical, and this is failing while building mathematical. The instructions I'm following are the cygwin section of this: https://gitlab.khronos.org/vulkan/vulkan/blob/1.0/doc/specs/vulkan/README.adoc

I have installed these cygwin packages using cygwin's setup-x86_64.exe:

liblasem0.4-devel
liblasem0.4_4

And I have created a symbolic link named liblasem.dll.a as recommended in the above-referenced README.adoc.

$ find /usr/lib -iname '*lasem*'
/usr/lib/liblasem-0.4.dll.a
/usr/lib/liblasem.dll.a
/usr/lib/pkgconfig/lasem-0.4.pc

Here are relevant excerpts from the build log:


$ MATHEMATICAL_USE_SYSTEM_LASEM=1 gem install asciidoctor-mathematical
Building native extensions.  This could take a while...
ERROR:  Error installing asciidoctor-mathematical:
        ERROR: Failed to build gem native extension.

    current directory: /home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical
/usr/bin/ruby.exe -r ./siteconf20170812-11152-bj7qdh.rb extconf.rb

[...]

rm -f mathematical.so
gcc -shared -o mathematical.so cairo_callbacks.o lasem_overrides.o mathematical.o -L. -L/usr/lib -L/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/lib -L. -fstack-protector -lgdk_pixbuf-2.0 -lm -lgmodule-2.0 -lpng16 -lm -lz -lcairo -lz -lpixman-1 -lfontconfig -lexpat -lfreetype -lexpat -lfreetype -lbz2 -lz -lpng16 -lm -lz -lxcb-shm -lxcb-render -lXrender -lXext -lX11 -lxcb -lXau -lXdmcp -lpango-1.0 -lm -lgobject-2.0 -lffi -lglib-2.0 -lintl -lpcre -lintl -liconv -lpcre -Wl,--export-all-symbols -Wl,--enable-auto-image-base,--enable-auto-import    -lruby230 -lpangocairo-1.0 -lxml2  -lpthread -lgmp -ldl -lcrypt   -lmtex2MML
mathematical.o: In function `process':
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:111: undefined reference to `lsm_dom_document_new_from_memory'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:111:(.text+0x6a9): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `lsm_dom_document_new_from_memory'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:122: undefined reference to `lsm_dom_document_create_view'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:122:(.text+0x6fb): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `lsm_dom_document_create_view'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:123: undefined reference to `lsm_dom_view_set_resolution'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:123:(.text+0x70a): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `lsm_dom_view_set_resolution'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:128: undefined reference to `lsm_dom_view_get_size'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:128:(.text+0x733): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `lsm_dom_view_get_size'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:129: undefined reference to `lsm_dom_view_get_size_pixels'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:129:(.text+0x748): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `lsm_dom_view_get_size_pixels'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:145: undefined reference to `lsm_dom_view_render'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:145:(.text+0x7a9): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `lsm_dom_view_render'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:145: undefined reference to `lsm_dom_view_render'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:145:(.text+0x88d): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `lsm_dom_view_render'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:145: undefined reference to `lsm_dom_view_render'
/home/jeff/.gem/ruby/2.3.0/gems/mathematical-1.6.9/ext/mathematical/mathematical.c:145:(.text+0xa0c): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `lsm_dom_view_render'
collect2: error: ld returned 1 exit status
make: *** [Makefile:257: mathematical.so] Error 1

make failed, exit code 2

gjtorikian / mathematical

Link error when using MATHEMATICAL_USE_SYSTEM_LASEM in Cygwin #77