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c++.command-line - optlink when invoked from dmc

reply Michael <Michael_member pathlink.com> writes:
I'm using bakefile to generate smake compliant makefiles for my project. The
bakefile uses optlink as the linker. Before migrating to bakefile I used my own
makefiles where I used dmc as the linker (of course I realize dmc is still
invoking the linker for me, but with some differences which I'll get to).

What's interesting is that by using dmc as the linker, dmc generates DEF files
for me for all of my DLLs which saves me quite a bit of work. When I run dmc for
compiling a DLL and a seperate invocation of optlink, I don't get the DEF file.
For this reason, my DLLs don't work (I get no output or crashes when linking an
executable with the DLL).

How can I force DMC to generate a DEF file for me? I know it has this capability
because I don't write DEF files but I do get them after compilation. Hmmm...now
that I think of it, it may be optlink that generates the DEF. I'm pretty certain
that I invoke dmc the same way so it can't be DMC generating the DEF files. In
any case, I'm not writing them myself.

As it stands, I can't get my DLLs to work if I invoke the linker itself.

-Michael
Aug 23 2005
parent reply "Walter" <newshound digitalmars.com> writes:
Why not just create a .def file and include it as a source file in your
build?
Aug 23 2005
parent reply Michael <Michael_member pathlink.com> writes:
In article <deg7un$2m0e$2 digitaldaemon.com>, Walter says...

Why not just create a .def file and include it as a source file in your
build?


Unfortunately because bakefile has no provisions for providing a DEF file
in it's linker command.

Bakefile has chosen to invoke optlink instead of dmc as it's linker, and by
doing so I can't really use it to create working DLLs.

-Michael
Aug 23 2005
parent reply "Włodzimierz Skiba" <abx abx.art.pl> writes:
Michael <Michael_member pathlink.com> wrote in
news:deggb5$22n$1 digitaldaemon.com: 


 For this reason, my DLLs don't work (I get no output or crashes when linking an
 executable with the DLL).


I'm expect that optlink called directly can do all the same as dmc on top of
it. So 
perhaps that there is just missing flag passed to optlink or additional
step/command 
before/after optlink invocation. Or perhaps there is an error somewhere not
catched. 
Definietly I need to know more about "don't work".


 Bakefile has chosen to invoke optlink instead of dmc as it's linker,
 and by doing so I can't really use it to create working DLLs.


I could optionally change that for future bakefiles as long as you could
provide me 
replacement.

if you look into bakefile/rules/makefile_defs_dmars_common.bkl which defines
dmars 
and dmars_smake formats it contains:

    <set var="__LINKER">link /NOLOGO /SILENT /NOI /DELEXECUTABLE</set>
    <set var="__LINKER_CC">$(__LINKER) /EXETYPE:NT</set>
    <set var="__LINKER_CXX">$(__LINKER) /EXETYPE:NT</set>
    <set var="__DLL_LINKER_CC">$(__LINKER)</set>
    <set var="__DLL_LINKER_CXX">$(__LINKER)</set>

and later in that file in <template id="__commands_templ"> there is linker
command 
specified. Please tell me how could dmc-based command look.    

Thanks!

ABX
Aug 24 2005
next sibling parent "Walter" <newshound digitalmars.com> writes:
dmc will create a default .def file if one is not specified on the command
line. It looks like:

    static char ntdlldef[] =
        "LIBRARY \"%s.dll\"\n"
        "DESCRIPTION '%s as a DLL'\n"
        "EXETYPE NT\n"
        "SUBSYSTEM WINDOWS\n"
        "CODE SHARED EXECUTE\n"
        "DATA WRITE\n";

for windows dll's. %s is the dll name. Hope this helps.
Aug 25 2005
prev sibling parent reply Michael <Michael_member pathlink.com> writes:
I could optionally change that for future bakefiles as long as you could
provide me 
replacement.


I've since had to switch from Digital Mars to MingW because the DM linker
frequently deadlocks when building on multiprocessor machines. It was just too
much of a headache to wake up to find a build stalled the next day. :-( I know
it's written in pure assembly, but the deadlock is a real problem. With chips
going mulitcore, this will begin to become more and more a problem for DMC.

But I will suggest that bakefile use dmc as the linker. Walter gave us the code
snippet of how dmc constructs the default DEF file. This really is necessary for
building DLLs. I could not get a working DLL built with the standalone linker. I
have the equivalent link command (to the default bakefile rule) written down
somewhere. Ah...found it.

Here is the link command that dmc generates (or so the console says):

link Foo+Bar+Hello,MyDll.dll,,SomeLib+ws2_32+advapi32+kernel32,MyDll/noi/implib

Notice that /NOI and /IMPLIB are automatically generated by dmc and the format
is a little different than from what bakefile produces. I'd get rid of the all
uppercase option names too. I think they are harder on the eyes. There is no map
file specified (unlike bakefile where you do name the map file in the linker
rule). Note that this link command produces a default .DEF file (but only when
invoked by dmc). I hope that helps.

-Michael
Aug 31 2005
parent "Walter" <newshound digitalmars.com> writes:
"Michael" <Michael_member pathlink.com> wrote in message
news:df5m3p$30l9$1 digitaldaemon.com...

 I've since had to switch from Digital Mars to MingW because the DM linker
 frequently deadlocks when building on multiprocessor machines. It was just


too

 much of a headache to wake up to find a build stalled the next day. :-( I


know

 it's written in pure assembly, but the deadlock is a real problem. With


chips

 going mulitcore, this will begin to become more and more a problem for


DMC.

Here's a workaround posted previously:
-------------------------------------------------------
I expect a workaround would be the same solution we used at work by
setting the processor affinity.

There is a utility that will set it. It's not the one we used but it
should do the job.

http://www.beyondlogic.org/solutions/processutil/processutil.htm
(Scroll near the bottom for the download)

Basically, you can tell the program to select a particular combination
of processors to run on using a bit mask. I've not tried it on
hyperthreaded machines only on dual processor machines but I believe
they appear the same to the OS so it should work.
-------------------------------------------------------------
Sep 01 2005