topic Re: IFX in the Intel® oneAPI 2022.3 Release in Intel® Fortran Compiler

Re: IFX in the Intel® oneAPI 2022.3 Release

hansderaedt — Tue, 26 Dec 2023 09:21:08 GMT

Hello,

I am not sure that this is the right place to post the following. If not, please direct me to the right place.

I have a problem migrating from ifort to ifx, related to building code with and without OpenMP.
IFORT works fine, but IFX does not.

There is no need to look at the source code, I believe (there is a USE omp_lib statement in the MAIN__).

System info: Windows 11 Pro 22H2 (22621.2861)

ifx /logo
Intel(R) Fortran Compiler for applications running on Intel(R) 64, Version 2023.2.0 Build 20230627
Copyright (C) 1985-2023 Intel Corporation. All rights reserved.

According to ifx /help:
/Qopenmp-stubs
enables the user to compile OpenMP programs in sequential mode. The
OpenMP directives are ignored and a stub OpenMP library is linked
(sequential)
ifort /logo
Intel(R) Fortran Intel(R) 64 Compiler Classic for applications running on Intel(R) 64, Version 2021.10.0 Build 20230609_000000

With OpenMP:
1. ifx /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /Qopenmp /Qopt-report /warn:nodeclarations "source files" /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:psa2.exe
Code runs well.

Without OpenMP, using the stub library:
2. ifx /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /warn:nodeclarations /Qopenmp-stubs "source files" /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:psa2noomp.exe
psa2.obj : error LNK2019: unresolved external symbol omp_get_num_procs referenced in function MAIN__
psa2.obj : error LNK2019: unresolved external symbol omp_get_max_threads referenced in function MAIN__
psa2noomp.exe : fatal error LNK1120: 2 unresolved externals
NMAKE : fatal error U1077: 'ifx /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /warn:nodeclarations /Qopenmp-stubs "source files" /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:psa2noomp.exe' : return code '0x460'
Stop.
Clearly, this one fails to link.

Without OpenMP, using the stub library:
3. ifort /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /warn:nodeclarations /Qopenmp-stubs "source files" /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:psa2noomp.exe
This one works, code runs well.

Any suggestions?

Best regards,
Hans De Raedt

Re: IFX in the Intel® oneAPI 2022.3 Release

Barbara_P_Intel — Tue, 26 Dec 2023 22:41:47 GMT

I compiled and ran a simple matmul that uses OpenMP directives. Using ifx it compiled and ran okay for me with /Qopenmp and again with /Qopenmp-stubs in a oneAPI command window on Windows.

Can you please upload an example that fails?

I used Intel(R) 64, Version 2024.0.0 Build 20231017. It was released about a month ago, around Thanksgiving.

Re: IFX in the Intel® oneAPI 2022.3 Release

hansderaedt — Wed, 27 Dec 2023 09:46:38 GMT

Thanks for the quick response. A minimal example is attached. The problem seems to be in the link step. Using IFORT there is no problem linking with the OpenMP stub but with IFX there seems to be one.

ifx /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /Qopenmp /Qopt-report ifxifort.f90 /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:ifxomp.exe

ifort /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /Qopenmp-stubs /Qdiag-disable:10448 ifxifort.f90 /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:ifortnoomp.exe

ifx /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /Qopenmp-stubs ifxifort.f90 /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:ifxnoomp.exe
ifxifort.obj : error LNK2019: unresolved external symbol omp_get_num_procs referenced in function MAIN__
ifxifort.obj : error LNK2019: unresolved external symbol omp_get_max_threads referenced in function MAIN__
ifxnoomp.exe : fatal error LNK1120: 2 unresolved externals
NMAKE : fatal error U1077: 'ifx /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /Qopenmp-stubs ifxifort.f90 /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:ifxnoomp.exe' : return code '0x460'
Stop.

Re: IFX in the Intel® oneAPI 2022.3 Release

andrew_4619 — Wed, 27 Dec 2023 11:33:52 GMT

ifx /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /Qopenmp /Qopt-report ifxifort.f90 /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:ifxomp.exe Volume in drive C is OS Volume Serial Number is 3257-09CB Directory of C:\Users\cadfi\OneDrive\Desktop\ifxtest 27/12/2023 11:09 <DIR> . 27/12/2023 11:07 <DIR> .. 27/12/2023 11:06 258 ifxifort.f90 27/12/2023 11:09 2,629 ifxifort.obj 27/12/2023 11:09 11,842 ifxifort.opt.yaml 27/12/2023 11:09 318 ifxifort.optrpt 27/12/2023 11:09 7,393,280 ifxifort.pdb 27/12/2023 11:09 1,080,832 ifxomp.exe 6 File(s) 8,489,159 bytes 2 Dir(s) 68,060,684,288 bytes free

I opened a x64 command window, downloaded your file, pasted your build command and it built ok. I think your install or omp version is broken.

ifxomp
omp_get_num_procs() = 12: the number of processors that are available to the device
omp_get_max_threads() = 12: the number of threads used to form a new team

Checking mu ENV I see:

I_MPI_ONEAPI_ROOT=C:\Program Files (x86)\Intel\oneAPI\mpi\2021.10.0
I_MPI_ROOT=C:\Program Files (x86)\Intel\oneAPI\mpi\latest\env\\..

Re: IFX in the Intel® oneAPI 2022.3 Release

hansderaedt — Wed, 27 Dec 2023 11:33:38 GMT

It is not clear to me if you also tried:

ifx /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /Qopenmp-stubs ifxifort.f90 /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:ifxnoomp.exe

My env says (yesterday I downloaded and installed version 2024.0.2):

I_MPI_ONEAPI_ROOT=C:\Program Files (x86)\Intel\oneAPI\mpi\2021.10.0
I_MPI_ROOT=C:\Program Files (x86)\Intel\oneAPI\2024.0
LIB=C:\Program Files (x86)\Intel\oneAPI\2024.0\lib;C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.38.33130\ATLMFC\lib\x64;C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.38.33130\lib\x64;C:\Program Files (x86)\Windows Kits\NETFXSDK\4.8\lib\um\x64;C:\Program Files (x86)\Windows Kits\10\lib\10.0.22621.0\ucrt\x64;C:\Program Files (x86)\Windows Kits\10\\lib\10.0.22621.0\\um\x64
LIBPATH=C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.38.33130\ATLMFC\lib\x64;C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.38.33130\lib\x64;C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.38.33130\lib\x86\store\references;C:\Program Files (x86)\Windows Kits\10\UnionMetadata\10.0.22621.0;C:\Program Files (x86)\Windows Kits\10\References\10.0.22621.0;C:\Windows\Microsoft.NET\Framework64\v4.0.30319
LIBRARY_PATH=C:\Program Files (x86)\Intel\oneAPI\2024.0\lib;

... >ifx
Intel(R) Fortran Compiler for applications running on Intel(R) 64, Version 2024.0.2 Build 20231213
Copyright (C) 1985-2023 Intel Corporation. All rights reserved.

Re: IFX in the Intel® oneAPI 2022.3 Release

andrew_4619 — Wed, 27 Dec 2023 12:51:15 GMT

OK yes the "stubs" generates the link error I had missed that option. That said I don't understand what the option means, is not a 'stub' library the one that has the references for dynamic linking via dlls? My understanding is that there is no static linking for openmp in ifort so if that is the case the option is redundant?

Re: IFX in the Intel® oneAPI 2022.3 Release

hansderaedt — Wed, 27 Dec 2023 13:11:32 GMT

According to ifx /help (or ifort /help) :
/Qopenmp-stubs
enables the user to compile OpenMP programs in sequential mode. The OpenMP directives are ignored and a stub OpenMP library is linked (sequential)

The option is very useful to test the code in sequential mode (without having to change anything to the source files).

Linking with the stub OpenMP library is expected to replace all OpenMP runtime procedures by "dummies" that give some default output.

If we replace ifx by ifort:

ifort /nologo /O3 /nodebug /nocheck /heap-arrays /Qdiag-error-limit:4 /warn:nodeclarations /Qopenmp-stubs "source files" /link /INCREMENTAL:NO /NOLOGO /OPT:NOREF /out:psa2noomp.exe

the build is ok and the code runs fine.

Just try the command above and run psa2noomp.exe to see the output.

My wild guess is that "ifx /Qopenmp-stubs" does not pass the name/path of the openmp-stubs library to the linker whereas "ifort /Qopenmp-stubs" does.

The libs are in C:\Program Files (x86)\Intel\oneAPI\2024.0\lib

libiomp5md.lib

libiompstubs5md.lib

Re: IFX in the Intel® oneAPI 2022.3 Release

andrew_4619 — Wed, 27 Dec 2023 14:26:58 GMT

OK I get that. I think you are correct becuase adding !DIR$OBJCOMMENT LIB:"libiompstubs5md.lib" to the source fixes it as a workaround.

Re: IFX in the Intel® oneAPI 2022.3 Release

Barbara_P_Intel — Wed, 27 Dec 2023 15:36:10 GMT

Thanks for the reproducer. I duplicated the link error with /Qopenmp-stubs. I first thought that all those compiler options may be causing the failure, but no. I'll keep investigating.

Q:\06093771>ifx /Qopenmp-stubs ifxifort.f90 Intel(R) Fortran Compiler for applications running on Intel(R) 64, Version 2024.0.0 Build 20231017 Copyright (C) 1985-2023 Intel Corporation. All rights reserved. Microsoft (R) Incremental Linker Version 14.38.33130.0 Copyright (C) Microsoft Corporation. All rights reserved. -out:ifxifort.exe -subsystem:console ifxifort.obj ifxifort.obj : error LNK2019: unresolved external symbol omp_get_num_procs referenced in function MAIN__ ifxifort.obj : error LNK2019: unresolved external symbol omp_get_max_threads referenced in function MAIN__ ifxifort.exe : fatal error LNK1120: 2 unresolved externals Q:\06093771>ifx /Qopenmp ifxifort.f90 Intel(R) Fortran Compiler for applications running on Intel(R) 64, Version 2024.0.0 Build 20231017 Copyright (C) 1985-2023 Intel Corporation. All rights reserved. Microsoft (R) Incremental Linker Version 14.38.33130.0 Copyright (C) Microsoft Corporation. All rights reserved. -out:ifxifort.exe -subsystem:console -defaultlib:libiomp5md.lib -nodefaultlib:vcomp.lib -nodefaultlib:vcompd.lib ifxifort.obj Q:\06093771>ifxifort.exe omp_get_num_procs() = 8: the number of processors that are available to the device omp_get_max_threads() = 8: the number of threads used to form a new team

Re:Re: IFX in the Intel® oneAPI 2022.3 Release

Barbara_P_Intel — Wed, 27 Dec 2023 16:24:29 GMT

Bug filed: CMPLRLLVM-54924.

Today my matmul fails to link with /Qopenmp-stubs. Wonder what I saw yesterday. Sigh...

Re: Re:Re: IFX in the Intel® oneAPI 2022.3 Release

JohnNichols — Wed, 27 Dec 2023 16:39:45 GMT

There is no need to sigh..., it was boxing day, a day of joy in the old Commonwealth Countries, where excess eggnog is removed by old grandmother's who like the taste of brandy, people stand in the wind on the beach in Norfolk and freeze to death, whilst bonding as a family, I await the oneapi to reinstall so I have some spare minutes, the difference between -infinity and +infinity is explained, of course we cannot count to infinity as there are not enough atoms in the universe, the Norseman suggests that I not get ahead of Intel and there is a web link for PRC people that leads nowhere that I can see would interest them on the Intel site,

So stay relaxed and just enjoy the cool weather. I can now return to programming.

Happy New Year.

Re:Re: IFX in the Intel® oneAPI 2022.3 Release

Barbara_P_Intel — Tue, 09 Apr 2024 21:54:03 GMT

With the ifx compiler version 2024.2.0 linking with /Qopenmp-stubs works on Windows.

Look for this release in mid-2024.