Libjpeg linking has always been broken (before, shared linking meant that since fltk pulls in libjpeg, no complaints were made). This isn't great, but it's because libjpeg doesn't have anything nice like a pkg-configure file.

src/Makefile.am

@@ -23,6 +23,12 @@ flarq_CFLAGS = $(flarq_CXXFLAGS)
 flarq_LDFLAGS = @FLARQ_BUILD_LDFLAGS@
 flarq_LDADD = @FLARQ_BUILD_LDADD@
 
+# UGLY HACK! libjpeg doesn't have a pkg-configure (.pc) file and I can't be bothered doing this properly
+# FLTK requires libjpeg so it's *fair to assume* (and I'm going to hell for that) that it will be around somewhere
+# It's up whoever's doing the MINGW32 build to direct us to the local static copy, typically by using the LPATH
+# environment variable. This is also required since a MINGW32 builder needs to tell FLTK where to find it by similar
+# means because of the nasty way their configure script behaves (it _just tries_ -ljpeg to "see if we have it installed")
+fldigi_LDFLAGS += -ljpeg
 
 HAMLIB_SRC = include/hamlib.h rigcontrol/hamlib.cxx include/rigclass.h rigcontrol/rigclass.cxx
 XMLRPC_SRC = include/xmlrpc.h misc/xmlrpc.cxx