3.4.2: issue with build `flexiblas` binaries

[kloczek]

I've manage to build my own flexiblas binaries and package all that as rpm package.
On top of that I've build my own python numpy binaries wiecha are using flexiblas however on any use of those numpy fails with core dump and flexiblas Failed to get the BLAS backend (OPENBLAS-OPENMP) from the configuration. message.
Fir example on building joblib python module documentation I have:

+ /usr/bin/sphinx-build -n -T -b man doc build/sphinx/man
Running Sphinx v7.2.6
flexiblas Failed to get the BLAS backend (OPENBLAS-OPENMP) from the configuration.
/var/tmp/rpm-tmp.Dgu6DF: line 59: 893244 Aborted                 (core dumped)

My understanding is that something is missing or even flexiblas is indirectly build however I'm struggling with diagnose this issue and error message does not point and what is missing/wwong.

May I ask for some help/hint? 🤔

flexiblas was build using cmake params:

%cmake \
        -D CMAKE_SKIP_INSTALL_RPATH=ON \
        -D INTEGER8=OFF \
        -D SYS_BLAS_LIBRARY=-lblas \
        -D SYS_LAPACK_LIBRARY=-llapack \
        -D TESTS=ON \

and after install flexiblas package flexiblas list shows

[tkloczko@pers-jacek SPECS]$ flexiblas list
System-wide:
System-wide (config directory):
 NETLIB
   library = libflexiblas_netlib.so
   comment =
User config:
Host config:
Enviroment config:

and flexiblas print

[tkloczko@pers-jacek SPECS]$ flexiblas print
FlexiBLAS, version 3.4.2
Copyright (C) 2013-2024 Martin Koehler and others.
This is free software; see the source code for copying conditions.
There is ABSOLUTELY NO WARRANTY; not even for MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.


Configured BLAS libraries:
System-wide (/etc/flexiblasrc):

System-wide from config directory (/etc/flexiblasrc.d/)
 NETLIB
   library = libflexiblas_netlib.so
   comment =

User config (/home/tkloczko/.flexiblasrc):

Host config (/home/tkloczko/.flexiblasrc.pers-jacek):

Available hooks:

Backend and hook search paths:
  /usr/lib64/flexiblas/

Default BLAS:
    System:       OPENBLAS-OPENMP
    User:         (none)
    Host:         (none)
    Active Default: OPENBLAS-OPENMP (System)
Run-time properties:
   verbose = 0 (System)

[Enchufa2]

Something against reusing this spec? :)

[kloczek]

Initially I've started my work on top of that spec.
Nevertheless what I've produces is not working as expected so I'm looking for how to diagnose this issue 🤔

[kloczek]

I've been trying to diagnose this issue using strace -fe trace=file usr/bin/sphinx-build -n -T -b man doc build/sphinx/man and to be hones cannot find anything which may cause this error message

[tkloczko@pers-jacek joblib-1.4.2]$ strace -fe trace=file /usr/bin/sphinx-build -n -T -b man doc build/sphinx/man
execve("/usr/bin/sphinx-build", ["/usr/bin/sphinx-build", "-n", "-T", "-b", "man", "doc", "build/sphinx/man"], 0x7ffe1952bfc0 /* 28 vars */) = 0
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3

[..]

openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 4
openat(AT_FDCWD, "/lib64/libflexiblas.so.3", O_RDONLY|O_CLOEXEC) = 4
access("/etc/flexiblasrc", F_OK)        = 0
openat(AT_FDCWD, "/etc/flexiblasrc", O_RDONLY) = 4
readlink("/etc", 0x7ffe50433dc0, 1023)  = -1 EINVAL (Invalid argument)
readlink("/etc/flexiblasrc", 0x7ffe50433dc0, 1023) = -1 EINVAL (Invalid argument)
newfstatat(AT_FDCWD, "/etc/flexiblasrc.d/", {st_mode=S_IFDIR|0755, st_size=22, ...}, 0) = 0
openat(AT_FDCWD, "/etc/flexiblasrc.d/", O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_DIRECTORY) = 4
openat(AT_FDCWD, "/etc/flexiblasrc.d//netlib.conf", O_RDONLY) = 5
readlink("/etc", 0x7ffe50433dc0, 1023)  = -1 EINVAL (Invalid argument)
readlink("/etc/flexiblasrc.d", 0x7ffe50433dc0, 1023) = -1 EINVAL (Invalid argument)
readlink("/etc/flexiblasrc.d/netlib.conf", 0x7ffe50433dc0, 1023) = -1 EINVAL (Invalid argument)
access("/home/tkloczko/.flexiblasrc", F_OK) = -1 ENOENT (No such file or directory)
access("/home/tkloczko/.flexiblasrc.pers-jacek", F_OK) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib64/flexiblas/", O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_DIRECTORY) = 4
access("libflexiblas_netlib.so", R_OK)  = -1 ENOENT (No such file or directory)
newfstatat(AT_FDCWD, "/usr/lib64/flexiblas//libflexiblas_netlib.so", {st_mode=S_IFREG|0755, st_size=44248, ...}, 0) = 0
openat(AT_FDCWD, "/usr/lib64/flexiblas//libflexiblas_netlib.so", O_RDONLY|O_CLOEXEC) = 4
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 4
openat(AT_FDCWD, "/lib64/libblas.so.3", O_RDONLY|O_CLOEXEC) = 4
openat(AT_FDCWD, "/lib64/libgfortran.so.5", O_RDONLY|O_CLOEXEC) = 4
access("libflexiblas_fallback_lapack.so", R_OK) = -1 ENOENT (No such file or directory)
newfstatat(AT_FDCWD, "/usr/lib64/flexiblas//libflexiblas_fallback_lapack.so", {st_mode=S_IFREG|0755, st_size=14952, ...}, 0) = 0
openat(AT_FDCWD, "/usr/lib64/flexiblas//libflexiblas_fallback_lapack.so", O_RDONLY|O_CLOEXEC) = 4
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 4
openat(AT_FDCWD, "/lib64/liblapack.so.3", O_RDONLY|O_CLOEXEC) = 4
flexiblas Failed to get the BLAS backend (OPENBLAS-OPENMP) from the configuration.
--- SIGABRT {si_signo=SIGABRT, si_code=SI_TKILL, si_pid=1081238, si_uid=1000} ---
+++ killed by SIGABRT (core dumped) +++

BTW: why flexiblas is trying to use DSO libflexiblas_fallback_lapack.so from current directory? 🤔
This may cause some security issues.
Is it possible to block that somehow? 🤔

[grisuthedragon]

Regarding your flexiblas print output you are trying to load a not known BLAS implementation. OpenBLAS-OpenMP is set in the config but not available. Since you are talking about an own RPM package, did you install all backends?

Can you show the content of /usr/lib64/flexiblas/?

[Enchufa2]

Even if you don't use my spec, this command may help you get all the build dependencies:

$ sudo dnf builddep flexiblas

[kloczek]

Can you show the content of /usr/lib64/flexiblas/?

[tkloczko@pers-jacek SPECS]$ ls -la /usr/lib64/flexiblas/
total 60
drwxr-xr-x 1 root root   106 May 10 19:41 .
dr-xr-xr-x 1 root root 23990 May 10 19:41 ..
-rwxr-xr-x 1 root root 14952 May 10 00:57 libflexiblas_fallback_lapack.so
-rwxr-xr-x 1 root root 44256 May 10 00:57 libflexiblas_netlib.so

[tkloczko@pers-jacek SPECS]$ flexiblas list
System-wide:
System-wide (config directory):
 NETLIB
   library = libflexiblas_netlib.so
   comment =
User config:
Host config:
Enviroment config:

[tkloczko@pers-jacek SPECS]$ flexiblas print
FlexiBLAS, version 3.4.2
Copyright (C) 2013-2024 Martin Koehler and others.
This is free software; see the source code for copying conditions.
There is ABSOLUTELY NO WARRANTY; not even for MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.


Configured BLAS libraries:
System-wide (/etc/flexiblasrc):

System-wide from config directory (/etc/flexiblasrc.d/)
 NETLIB
   library = libflexiblas_netlib.so
   comment =

User config (/home/tkloczko/.flexiblasrc):

Host config (/home/tkloczko/.flexiblasrc.pers-jacek):

Available hooks:

Backend and hook search paths:
  /usr/lib64/flexiblas/

Default BLAS:
    System:       OPENBLAS-OPENMP
    User:         (none)
    Host:         (none)
    Active Default: OPENBLAS-OPENMP (System)
Run-time properties:
   verbose = 0 (System)

[kloczek]

Any hints/advices? 🤔

[grisuthedragon]

You missing installing the backends. The folder

ls -la /usr/lib64/flexiblas/
total 60
drwxr-xr-x 1 root root   106 May 10 19:41 .
dr-xr-xr-x 1 root root 23990 May 10 19:41 ..
-rwxr-xr-x 1 root root 14952 May 10 00:57 libflexiblas_fallback_lapack.so
-rwxr-xr-x 1 root root 44256 May 10 00:57 libflexiblas_netlib.so

only contains the netlib implementation and the falllback codes for LAPACK. But in your runtime config you are trying to load OPENBLAS-OPENMP which seem to be not installed.

You have two options...

1. install FlexiBLAS properly, e.g. by installing sudo dnf builddep flexiblas first
2. remove OpenBLAS-OPENMP from your system-wide config.

[kloczek]

Issue is that i my case libflexiblas_openblas-openmp.so is not compiled, linked and installed.
here is cmake output

+ /usr/bin/cmake -B x86_64-redhat-linux-gnu -D BUILD_SHARED_LIBS=ON -D CMAKE_AR=/usr/bin/gcc-ar -D CMAKE_BUILD_TYPE=RelWithDebInfo -D CMAKE_C_FLAGS_RELEASE=-DNDEBUG -D CMAKE_CXX_FLAGS_RELEASE=-DNDEBUG -D CMAKE_Fortran_FLAGS_RELEASE=-DNDEBUG -D CMAKE_INSTALL_PREFIX=/usr -D CMAKE_NM=/usr/bin/gcc-nm -D CMAKE_RANLIB=/usr/bin/gcc-ranlib -D CMAKE_VERBOSE_MAKEFILE=ON -D INCLUDE_INSTALL_DIR=/usr/include -D LIB_INSTALL_DIR=/usr/lib64 -D LIB_SUFFIX=64 -D SHARE_INSTALL_PREFIX=/usr/share -D SYSCONF_INSTALL_DIR=/etc -S . -D CMAKE_SKIP_INSTALL_RPATH=ON -D INTEGER8=OFF -D LAPACK_API_VERSION=3.4.2 -D SYS_BLAS_LIBRARY=-lblas -D SYS_LAPACK_LIBRARY=-llapack -D TESTS=ON
CMake Warning (dev) at CMakeLists.txt:4 (PROJECT):
  cmake_minimum_required() should be called prior to this top-level project()
  call.  Please see the cmake-commands(7) manual for usage documentation of
  both commands.
This warning is for project developers.  Use -Wno-dev to suppress it.

-- The C compiler identification is GNU 14.1.1
-- The Fortran compiler identification is GNU 14.1.1
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/gcc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting Fortran compiler ABI info
-- Detecting Fortran compiler ABI info - done
-- Check for working Fortran compiler: /usr/bin/gfortran - skipped
-- Configuring FlexiBLAS 3.4.2
-- SYSCONFDIR: /etc
-- LIBDIR:     /usr/lib64
-- BINDIR:     /usr/bin
-- INCLUDEDIR: /usr/include
-- MANDIR:     /usr/share/man
-- Compiler_ID: GNU
-- FCompiler_ID: GNU
-- Fortran compiler supports -frecursive
-- Fortran compiler supports -fPIC
-- Fortran compiler supports -O3
-- Fortran compiler supports -Wimplicit-procedure
-- Fortran compiler supports -Wall
-- Fortran compiler supports -Wunused
-- Fortran compiler supports -Warray-temporaries
-- Fortran compiler supports -fbacktrace
-- Fortran compiler supports -Wshadow
-- Fortran compiler supports -O0
-- Performing Test C_W_PEDANTIC
-- Performing Test C_W_PEDANTIC - Success
-- Performing Test C_W_STRICT_PROTOTYPES
-- Performing Test C_W_STRICT_PROTOTYPES - Success
-- Performing Test C_W_CAST_QUAL
-- Performing Test C_W_CAST_QUAL - Success
-- Performing Test C_STACK_PROTECTOR
-- Performing Test C_STACK_PROTECTOR - Success
-- Performing Test C_STACK_CLASH
-- Performing Test C_STACK_CLASH - Success
-- Performing Test FC_STACK_PROTECTOR
-- Performing Test FC_STACK_PROTECTOR - Success
-- Performing Test FC_STACK_CLASH
-- Performing Test FC_STACK_CLASH - Success
-- Detecting Fortran/C Interface
-- Detecting Fortran/C Interface - Found GLOBAL and MODULE mangling
-- Verifying Fortran/C Compiler Compatibility
-- Verifying Fortran/C Compiler Compatibility - Success
-- Check for Thread Local Storage
-- Performing Test HAVE_THREAD_LOCAL
-- Performing Test HAVE_THREAD_LOCAL - Success
-- Performing Test HAVE__THREAD_LOCAL
-- Performing Test HAVE__THREAD_LOCAL - Success
-- Performing Test HAVE_GNU_THREAD_LOCAL
-- Performing Test HAVE_GNU_THREAD_LOCAL - Success
-- Looking for include file dlfcn.h
-- Looking for include file dlfcn.h - found
-- Looking for include file sys/sysmacro.h
-- Looking for include file sys/sysmacro.h - not found
-- Looking for include file sys/stat.h
-- Looking for include file sys/stat.h - found
-- Looking for RTLD_GLOBAL
-- Looking for RTLD_GLOBAL - found
-- Looking for RTLD_DEEPBIND
-- Looking for RTLD_DEEPBIND - found
-- Looking for RTLD_NOW
-- Looking for RTLD_NOW - found
-- Looking for RTLD_NODELETE
-- Looking for RTLD_NODELETE - found
-- Looking for dlopen
-- Looking for dlopen - found
-- Looking for dlopen
-- Looking for dlopen - found
-- Check for __attribute__((constructor))
-- Looking for attribute:  constructor  - works
-- Check for __attribute__((alias("foo")))
-- Looking for attribute:  alias("foo")  - works
-- Check for __attribute__((visibility("hidden")))
-- Looking for attribute:  visibility("hidden")  - works
-- Check for __attribute__((visibility("default")))
-- Looking for attribute:  visibility("default")  - works
-- Check for __attribute__((unused))
-- Looking for attribute:  unused  - works
-- libcscutils in project build

-- LIBCSCUTILS Features
-- Enable module: inifile
-- Enable module: ds

-- Check Generic Functionality
-- Check for __attribute__((constructor))
-- Looking for attribute:  constructor  - works
-- Check for __attribute__((deprecated))
-- Looking for attribute:  deprecated  - works
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Success
-- Found Threads: TRUE
-- Looking for pthread_yield
-- Looking for pthread_yield
-- Looking for pthread_yield - not found
-- Looking for pthread_yield
-- Looking for pthread_yield - not found
-- Looking for pthread_yield
-- Looking for pthread_yield - not found
-- Looking for pthread_yield
-- Looking for pthread_yield - not found
-- Looking for pthread_yield
-- Looking for pthread_yield - not found
-- Looking for pthread_yield
-- Looking for pthread_yield - not found
-- Looking for pthread_yield
-- Looking for pthread_yield - not found
-- Looking for pthread_yield - not found.
-- Looking for include file execinfo.h
-- Looking for include file execinfo.h - found
-- Looking for backtrace
-- Looking for backtrace - found
-- Looking for backtrace_symbols
-- Looking for backtrace_symbols - found
-- Enable csc_show_backtrace.
-- Looking for strnlen
-- Looking for strnlen
-- Looking for strnlen - not found
-- Looking for strnlen
-- Looking for strnlen - not found
-- Looking for strnlen
-- Looking for strnlen - not found
-- Looking for strnlen
-- Looking for strnlen - found
-- Looking for strnlen - found (using _POSIX_C_SOURCE=200809L).
-- Looking for strndup
-- Looking for strndup
-- Looking for strndup - not found
-- Looking for strndup
-- Looking for strndup - not found
-- Looking for strndup
-- Looking for strndup - not found
-- Looking for strndup
-- Looking for strndup - found
-- Looking for strndup - found (using _POSIX_C_SOURCE=200809L).
-- Looking for include file sys/ioctl.h
-- Looking for include file sys/ioctl.h - found
-- Looking for include file unistd.h
-- Looking for include file unistd.h - found
-- Looking for getline
-- Looking for getline
-- Looking for getline - not found
-- Looking for getline
-- Looking for getline - not found
-- Looking for getline
-- Looking for getline - not found
-- Looking for getline
-- Looking for getline - found
-- Looking for getline - found (using _POSIX_C_SOURCE=200809L).
-- Looking for getdelim
-- Looking for getdelim
-- Looking for getdelim - not found
-- Looking for getdelim
-- Looking for getdelim - not found
-- Looking for getdelim
-- Looking for getdelim - not found
-- Looking for getdelim
-- Looking for getdelim - found
-- Looking for getdelim - found (using _POSIX_C_SOURCE=200809L).

-- Features for CSC-INIFILE
-- Looking for realpath
-- Looking for realpath
-- Looking for realpath - found
-- Looking for realpath - found (using _NONE_).

-- External Libraries
-- Could NOT find CPUFREQ (missing: CPUFREQ_LIBRARIES CPUFREQ_INCLUDE_DIR)
CPUFREQ not found. Either cpufreq.h or libcpupower.so is missing.
-- Looking for strdup
-- Looking for strdup
-- Looking for strdup - not found
-- Looking for strdup
-- Looking for strdup - not found
-- Looking for strdup
-- Looking for strdup - not found
-- Looking for strdup
-- Looking for strdup - found
-- Looking for strdup - found (using _POSIX_C_SOURCE=200809L).
-- Looking for realpath
-- Looking for realpath
-- Looking for realpath - found
-- Looking for realpath - found (using _NONE_).
-- Use external LAPACK from -llapack with API_VERSION 3.4.2
CMake Warning at cmake/lapack.cmake:242 (MESSAGE):
  The requested LAPACK_VERSION is less than 3.6.1.  We recommend to use a
  newer API version.
Call Stack (most recent call first):
  CMakeLists.txt:352 (INCLUDE)


-- Use system provided NETLIB BLAS for fallback generation. SYS_BLAS_LIBRARY = -lblas
-- Use system provided LAPACK for fallback generation. SYS_LAPACK_LIBRARY = -llapack
-- Found OpenMP_C: -fopenmp (found version "4.5")
-- Found OpenMP_Fortran: -fopenmp (found version "4.5")
-- Found OpenMP: TRUE (found version "4.5")
-- OpenBLAS-Serial:  Candidate: /usr/lib64/libopenblas.so
-- OpenBLAS-Serial:  /usr/lib64/libopenblas.so does not contain the Serial version of OpenBLAS.
-- Could NOT find OpenBLASSerial (missing: OpenBLASSerial_LIBRARY)
-- OpenBLASSerial not found.
-- OpenBLAS-PThread:  Candidate: /usr/lib64/libopenblas.so
-- Found OpenBLASPThread: /usr/lib64/libopenblas.so
-- Build BLAS interface: OpenBLASPThread
-- Libs: /usr/lib64/libopenblas.so
-- Build additional BLAS interface: OpenBLASPThread
-- -- Libs: /usr/lib64/libopenblas.so
-- -- Linker Flags:
-- Performing Test ZDOTC_MKL
-- Performing Test ZDOTC_MKL - Failed
-- Looking for flexiblas_exit
-- Looking for flexiblas_exit - not found
-- Looking for Fortran DAXPY
-- Looking for Fortran DAXPY - found
-- Looking for cblas_daxpy
-- Looking for cblas_daxpy - found
-- Looking for MKL_Get_Version
-- Looking for MKL_Get_Version - not found
-- Add CBLAS in dummy library
-- OpenBLAS-OpenMP:  Candidate: /usr/lib64/libopenblas.so
-- OpenBLAS-OpenMP:  /usr/lib64/libopenblas.so does not contain the OpenMP version of OpenBLAS.
-- Could NOT find OpenBLASOpenMP (missing: OpenBLASOpenMP_LIBRARY)
-- OpenBLASOpenMP not found.
-- Could NOT find BlisSerial (missing: BlisSerial_LIBRARY)
-- BlisSerial not found.
-- Could NOT find BlisPThread (missing: BlisPThread_LIBRARY)
-- BlisPThread not found.
-- Could NOT find BlisOpenMP (missing: BlisOpenMP_LIBRARY)
-- BlisOpenMP not found.
-- Search for MKL: mkl_gf_lp64 mkl_sequential mkl_core
-- MklSerial not found.
-- Search for MKL: mkl_gf_lp64 mkl_gnu_thread mkl_core
-- MklOpenMP not found.
-- PP:
-- SP:
-- MKL_TBB depends on TBB. Not Found.
-- MklTBB not found.
--
-- Search for ATLAS
-- A library with BLAS API not found. Please specify library location.
--
-- Search for Apple
-- A library with BLAS API not found. Please specify library location.
-- Default BLAS  not found. Use NETLIB instead.
-- Found hook directory.
-- Build profile hook.
-- Enable Multithread Demo
-- Build Extra Benchmarks
-- OpenBLASPThread - /usr/lib64/libopenblas.so -
-- Found PythonInterp: /usr/bin/python3
-- Found Python (3.10.14): /usr/include/python3.10
-- Enable Testing...
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/sblat1.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/sblat2.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/sblat3.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/dblat1.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/dblat2.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/dblat3.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/cblat1.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/cblat2.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/cblat3.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/zblat1.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/zblat2.in
-- /home/tkloczko/rpmbuild/BUILD/flexiblas-3.4.2/test/blas/zblat3.in
-- ------------------------------------------------
--       Final Configuration Status
-- ------------------------------------------------
-- Build 8 byte integer: OFF
-- Build CBLAS interface: ON
-- Install path: /usr
-- Extra BLAS search path: /usr/lib64/flexiblas/
-- LAPACK Support: ON
-- LAPACK_API_VERSION: 3.4.2
-- ABI: GNU
-- Interface to Extra BLAS Libraries:
--  /usr/lib64/libopenblas.so - OpenBLASPThread
-- Default BLAS: NETLIB
--
-- Compiler Options:
--  CMAKE_C_FLAGS               = -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -O2 -g -grecord-gcc-switches -pipe -mtls-dialect=gnu2 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -fdata-sections -ffunction-sections -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -flto=auto -Wp,-U_FORTIFY_SOURCE,-D_FORTIFY_SOURCE=3 -Wp,-D_GLIBCXX_ASSERTIONS -Wall -Werror=format-security -fPIC -std=c99 -fstack-protector-strong -fstack-clash-protection -D_FILE_OFFSET_BITS=64
--  CMAKE_C_FLAGS_RELEASE       = -DNDEBUG -O3 -Wpedantic -Wstrict-prototypes -Wcast-qual
--  CMAKE_C_FLAGS_DEBUG         = -g -Wall -Wunused -g -Wextra -Wshadow -Wstrict-aliasing -Wundef -Wlogical-op -Wparentheses -Wcast-qual -O0 -Wpedantic -Wstrict-prototypes -Wcast-qual
--  CMAKE_Fortran_FLAGS         = -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -O2 -g -grecord-gcc-switches -pipe -mtls-dialect=gnu2 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -fdata-sections -ffunction-sections -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -flto=auto -Wp,-U_FORTIFY_SOURCE,-D_FORTIFY_SOURCE=3 -Wp,-D_GLIBCXX_ASSERTIONS -Wall -Werror=format-security -I/usr/lib64/gfortran/modules -frecursive -fPIC -fstack-protector-strong -fstack-clash-protection
--  CMAKE_Fortran_FLAGS_RELEASE = -DNDEBUG -O3
--  CMAKE_Fortran_FLAGS_DEBUG   = -g -Wimplicit-procedure -Wall -Wunused -Warray-temporaries -fbacktrace -Wshadow -O0
-- ------------------------------------------------
-- Configuring done (23.3s)
-- Generating done (0.5s)
CMake Warning:
  Manually-specified variables were not used by the project:

    INCLUDE_INSTALL_DIR
    LIB_INSTALL_DIR
    LIB_SUFFIX
    SHARE_INSTALL_PREFIX
    SYSCONF_INSTALL_DIR

I'm building temporary flexiblas without blis and atlas installed.

[kloczek]

Above cmake produces only belom list of loadable modules

-rwxr-xr-x 1 tkloczko tkloczko  14952 May 13 11:56 libflexiblas_fallback_lapack.so
-rwxr-xr-x 1 tkloczko tkloczko  15688 May 13 11:56 libflexiblas_hook_dummy.so
-rwxr-xr-x 1 tkloczko tkloczko 819336 May 13 11:56 libflexiblas_hook_profile.so
-rwxr-xr-x 1 tkloczko tkloczko  44256 May 13 11:56 libflexiblas_netlib.so
-rwxr-xr-x 1 tkloczko tkloczko  39744 May 13 11:56 libflexiblas_openblas-threads.so

[grisuthedragon]

Now, setting the default BLAS to OpenBLASPThread should enable to run everything with OpenBLAS.

[kloczek]

But it still do not explain why openblas-openmp backend is not build.

[grisuthedragon]

The log shows

-- OpenBLAS-OpenMP:  Candidate: /usr/lib64/libopenblas.so
-- OpenBLAS-OpenMP:  /usr/lib64/libopenblas.so does not contain the OpenMP version of OpenBLAS.

so the OpenBLAS version installed on your system is built with Pthreads support and not with OpenMP support.

[kloczek]

I don't see anything about OpenMP support in OpenBLAS 0.3.27 cmake output

+ /usr/bin/cmake -B x86_64-redhat-linux-gnu -D BUILD_SHARED_LIBS=ON -D CMAKE_AR=/usr/bin/gcc-ar -D CMAKE_BUILD_TYPE=RelWithDebInfo -D CMAKE_C_FLAGS_RELEASE=-DNDEBUG -D CMAKE_CXX_FLAGS_RELEASE=-DNDEBUG -D CMAKE_Fortran_FLAGS_RELEASE=-DNDEBUG -D CMAKE_INSTALL_PREFIX=/usr -D CMAKE_NM=/usr/bin/gcc-nm -D CMAKE_RANLIB=/usr/bin/gcc-ranlib -D CMAKE_VERBOSE_MAKEFILE=ON -D INCLUDE_INSTALL_DIR=/usr/include -D LIB_INSTALL_DIR=/usr/lib64 -D LIB_SUFFIX=64 -D SHARE_INSTALL_PREFIX=/usr/share -D SYSCONF_INSTALL_DIR=/etc -S . -D BUILD_STATIC_LIBS=OFF -D BUILD_TESTING=ON -D BUILD_WITHOUT_CBLAS=OFF -D BUILD_WITHOUT_LAPACK=OFF -D CPP_THREAD_SAFETY_GEMV=ON -D CPP_THREAD_SAFETY_TEST=ON -D DYNAMIC_ARCH=OFF -D INTERFACE64=OFF -D USE_LOCKING=OFF -D USE_PERL=ON
CMake Deprecation Warning at CMakeLists.txt:5 (cmake_minimum_required):
  Compatibility with CMake < 3.5 will be removed from a future version of
  CMake.

  Update the VERSION argument <min> value or use a ...<max> suffix to tell
  CMake that the project does not need compatibility with older versions.


-- The C compiler identification is GNU 14.1.1
-- The ASM compiler identification is GNU
-- Found assembler: /usr/bin/gcc
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/gcc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
CMake Warning at CMakeLists.txt:101 (message):
  CMake support is experimental.  It does not yet support all build options
  and may not produce the same Makefiles that OpenBLAS ships with.


CMake Warning (dev) at cmake/system_check.cmake:13 (if):
  Policy CMP0054 is not set: Only interpret if() arguments as variables or
  keywords when unquoted.  Run "cmake --help-policy CMP0054" for policy
  details.  Use the cmake_policy command to set the policy and suppress this
  warning.

  Quoted variables like "LINUX" will no longer be dereferenced when the
  policy is set to NEW.  Since the policy is not set the OLD behavior will be
  used.
Call Stack (most recent call first):
  cmake/system.cmake:8 (include)
  CMakeLists.txt:104 (include)
This warning is for project developers.  Use -Wno-dev to suppress it.

-- Looking for stdatomic.h
-- Looking for stdatomic.h - found
-- GEMM multithread threshold set to 4.
-- Multi-threading enabled with 48 threads.
-- Looking for a Fortran compiler
-- Looking for a Fortran compiler - /usr/bin/gfortran
-- The Fortran compiler identification is GNU 14.1.1
-- Detecting Fortran compiler ABI info
-- Detecting Fortran compiler ABI info - done
-- Check for working Fortran compiler: /usr/bin/gfortran - skipped
-- Running getarch
-- GETARCH results:
CORE=SKYLAKEX
LIBCORE=skylakex
NUM_CORES=48
HAVE_MMX=1
HAVE_SSE=1
HAVE_SSE2=1
HAVE_SSE3=1
HAVE_SSSE3=1
HAVE_SSE4_1=1
HAVE_SSE4_2=1
HAVE_AVX=1
HAVE_AVX2=1
HAVE_AVX512VL=1
HAVE_FMA3=1
MAKEFLAGS += -j 48

-- Compiling a 64-bit binary.
-- Building Single Precision
-- Building Double Precision
-- Building Complex Precision
-- Building Double Complex Precision
-- /home/tkloczko/rpmbuild/BUILD/OpenBLAS-0.3.27/x86_64-redhat-linux-gnu/interface/CMakeFiles/scopy.c

[..]

-- /home/tkloczko/rpmbuild/BUILD/OpenBLAS-0.3.27/x86_64-redhat-linux-gnu/lapack/CMakeFiles/ztrti2_LU.c
-- fortran lapack
-- Building deprecated routines
-- Building Single Precision
-- Building Double Precision
-- Building Single Precision Complex
-- Building Double Precision Complex
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Success
-- Found Threads: TRUE
-- The CXX compiler identification is GNU 14.1.1
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/g++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Generating openblas_config.h in include/openblas
-- Generating f77blas.h in include/openblas
-- Generating cblas.h in include/openblas
-- Copying LAPACKE header files to include/openblas
-- Configuring done (6.7s)
-- Generating done (1.3s)

[grisuthedragon]

Try compiling OpenBLAS with the standard makefile, e.g.

make USE_OPENMP=1