dynamic loading in static exe

[Paul Kienzle]

All,

I've been playing with dynamic loading into statically
linked octave.  The attached tarball demonstrates the
case of a dynamically loaded function calling back into
the main exe under mingw.  I know similar things are
possible on IRIX, and I believe they are under Linux.
I don't know about OS/X.

The question is, do we want to support it?  Is there
any advantage to static linking under Windows, other
than fewer files to work with?  

Andy and I have noticed that oct-files are large even 
when stripped, but we can get that benefit back for 
pre-packaged oct-files by reintroducing  
        --disable-lite-kernel 
or at least on windows, by clearing ENABLE_DYNAMIC_LINKING 
even if --enable-shared.

Paul Kienzle
address@hidden

For archiving convenience, here is the Makefile:

%.o: %.c ; $(CC) $(CFLAGS) -c -o $@ $<

# objects included in the exe that
# dl objects can refer to.
OBJS=dynmain.o

# objects included in the exe that
# dl objects cannot refer to.
MAINOBJ=main.o

# dl objects
SO=dynsub.dll

# main program name
PROG=testdyn

all: $(SO) $(PROG).exe

dynsub.dll: dynsub.o lib$(PROG).a
        gcc -shared -Wl,--export-all-symbols -Wl,--enable-auto-import dynsub.o 
-o dynsub.dll -L. -l$(PROG)

$(PROG).def: $(OBJS)
        # guess the export definitions from the objects
        dlltool --export-all --output-def $(PROG).def $(OBJS)

lib$(PROG).a: $(PROG).def
        # create the import symbols from the export definitions
        dlltool --dllname $(PROG).exe --def $(PROG).def --output-lib 
lib$(PROG).a

$(PROG).exe: $(MAINOBJ) lib$(PROG).a
        # create the export symbols from the export definitions
        dlltool --dllname $(PROG).exe --output-exp $(PROG).exp --def $(PROG).def
        # create the exe, including the export symbols
        gcc -o $(PROG).exe $(PROG).exp $(MAINOBJ) $(OBJS) -L. -l$(PROG)

clean:
        rm -f *.{o,a,exe,dll,exp,def}

testdyn.tar.gz
Description: application/tar-gz