rdma-core-46.0-1.fc39 fails to build in Fedora 39:

+ /usr/bin/cmake -S . -B redhat-linux-build -DCMAKE_C_FLAGS_RELEASE:STRING=-DNDEBUG -DCMAKE_CXX_FLAGS_RELEASE:STRING=-DNDEBUG -DCMAKE_Fortran_FLAGS_RELEASE:STRING=-DNDEBUG -DCMAKE_VERBOSE_MAKEFILE:BOOL=ON -DCMAKE_INSTALL_DO_STRIP:BOOL=OFF -DCMAKE_INSTALL_PREFIX:PATH=/usr -DINCLUDE_INSTALL_DIR:PATH=/usr/include -DLIB_INSTALL_DIR:PATH=/usr/lib64 -DSYSCONF_INSTALL_DIR:PATH=/etc -DSHARE_INSTALL_PREFIX:PATH=/usr/share -DLIB_SUFFIX=64 -DBUILD_SHARED_LIBS:BOOL=ON -GNinja -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_BINDIR:PATH=/usr/bin -DCMAKE_INSTALL_SBINDIR:PATH=/usr/sbin -DCMAKE_INSTALL_LIBDIR:PATH=/usr/lib64 -DCMAKE_INSTALL_LIBEXECDIR:PATH=/usr/libexec -DCMAKE_INSTALL_LOCALSTATEDIR:PATH=/var -DCMAKE_INSTALL_SHAREDSTATEDIR:PATH=/var/lib -DCMAKE_INSTALL_INCLUDEDIR:PATH=/usr/include -DCMAKE_INSTALL_INFODIR:PATH=/usr/share/info -DCMAKE_INSTALL_MANDIR:PATH=/usr/share/man -DCMAKE_INSTALL_SYSCONFDIR:PATH=/etc -DCMAKE_INSTALL_SYSTEMD_SERVICEDIR:PATH=/usr/lib/systemd/system -DCMAKE_INSTALL_INITDDIR:PATH=/etc/rc.d/init.d -DCMAKE_INSTALL_RUNDIR:PATH=/run -DCMAKE_INSTALL_DOCDIR:PATH=/usr/share/doc/rdma-core -DCMAKE_INSTALL_UDEV_RULESDIR:PATH=/usr/lib/udev/rules.d -DCMAKE_INSTALL_PERLDIR:PATH=/usr/share/perl5/vendor_perl -DENABLE_IBDIAGS_COMPAT:BOOL=True -DPYTHON_EXECUTABLE:PATH=/usr/bin/python3 -DCMAKE_INSTALL_PYTHON_ARCH_LIB:PATH=/usr/lib64/python3.11/site-packages -DNO_PYVERBS=0
-- The C compiler identification is GNU 13.1.1
-- 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
CMake Error at buildlib/RDMA_EnableCStd.cmake:63 (CHECK_C_SOURCE_COMPILES):
  Unknown CMake command "CHECK_C_SOURCE_COMPILES".
Call Stack (most recent call first):
  CMakeLists.txt:209 (RDMA_Check_C_Compiles)
-- Configuring incomplete, errors occurred!

A difference between passing and failing build root is at <https://koschei.fedoraproject.org/build/15603625>. An upgrade of cmake from 3.26.4-4.fc39 to 3.27.0~rc1-1.fc39 looks suspicious.

Reproducible: Always