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Custom DLL Build tool

pat726627
Beginner
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Hi,

Just a quick question about the custom DLL build tool in MKL release 10.0 (update 1). I have successfully created a custom DLL with 4 MKL functions (namely DSYEV, DPOTRF, DGEMM, DGESVD) and link it with my own DLL library.

If I want to distribute my library, do I need to include other MKL DLLs as well (such as libguide40.dll) other than the custom built DLL?

Thanks!
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7 Replies
TimP
Honored Contributor III
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You should be able to use dumpbin to check for dependencies. If you used mkl_sequential, libguide would certainly not be needed.
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pat726627
Beginner
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how do I specify the mkl_sequential option in the custom DLL builder? There are only interface, export, name, and xerbla options.
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Andrey_G_Intel2
Employee
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You can specify sequential mkl usage by setting value of "threading" option to "sequential". For more help about custom dll builder tool options, put "nmake help" command in custom dll builder tool folder.

Andrey

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pat726627
Beginner
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Thanks for the quick reply! I have tried out the "threading=sequential" flag in the custom DLL build tool. However the resulting DLL still has a dependency on the libguide40.dll.

The nmake command is:

nmake ia32 interface=cdecl threading=sequential export=mkl_func_list.txt name=mkl_utils

With the corresponding output from the custom builder:

1>Microsoft Program Maintenance Utility Version 8.00.50727.762
1>Copyright (C) Microsoft Corporation. All rights reserved.
1> if exist . emp_cdll rd /q /s . emp_cdll
1>Microsoft Library Manager Version 8.00.50727.762
1>Copyright (C) Microsoft Corporation. All rights reserved.
...
1> link /DLL /MACHINE:IX86 /NODEFAULTLIB /def:user_def_file.def . emp_cdll*.obj ....ia32libmkl_intel_c.lib ....ia32libmkl_intel_thread.lib ....ia32libmkl_core.lib ....ia32libmkl_solver.lib ....ia32liblibguide40.lib msvcrt.lib kernel32.lib user32.lib /out:mkl_utils.dll
1>Microsoft Incremental Linker Version 8.00.50727.762
1>Copyright (C) Microsoft Corporation. All rights reserved.
1> Creating library mkl_utils.lib and object mkl_utils.exp

It seems like the custom builder just ignore the threading option, and that can be confirmed by these lines under the "ia32:" section in the makefile:

ia32:
@echo EXPORTS > user_def_file.def
...
link /DLL /MACHINE:IX86 /NODEFAULTLIB /def:user_def_file.def
. emp_cdll*.obj $(xerbla)
$(IFACE_LIB_32)
$(mkl32_libpath)mkl_intel_thread.lib
$(mkl32_libpath)mkl_core.lib
$(mkl32_libpath)mkl_solver.lib
$(mkl32_libpath)libguide40.lib
msvcrt.lib kernel32.lib user32.lib /out:$(name).dll

Of course I can just go ahead and change libguide40.lib to libguide.lib (static version) as well as the mkl_intel_thread.lib in the makefile, but I would like to know if there is a better/right way to correct this problem?

Thank you very much!!
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Vladimir_Lunev
New Contributor I
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Hi!

This is a bug in the makefile for the case ia32. We'll fix it in the next MKL release.

Please, change mkl_intel_thread.lib to mkl_sequential.lib in the target ia32. Also, if you uses sequential MKL, you can remove libguide from the linker command line at all.

Vladimir

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pat726627
Beginner
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Thanks! It is all working now.

Just a related question: what's the different between linking it against mkl_intel_sequential.lib and libguide.lib?
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TimP
Honored Contributor III
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mkl_sequential limits multi-threaded operations to single threaded, stubbing out all OpenMP references, so that libguide is not required. mkl_thread passes parallel operations on to libguide or libiomp.
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