CMake Error: Unknown argument --cxxflags=-include stdint.h

[pgoddard08]

Hello,

When I attempt to build E3SMv2.1, I am getting a build error here:

   Calling /N/project/MSB_Project/E3SMv2.1_original/E3SM/share/build/buildlib.kokkos
ERROR: /N/project/MSB_Project/E3SMv2.1_original/E3SM/share/build/buildlib.kokkos FAILED

The error looks like:

cmake --with-serial --cxxflags='-include stdint.h' -DCMAKE_CXX_COMPILER=/geode2/soft/hps/sles15sp6/intel/2025.2.0.527/compiler/2025.2/bin/icpx -DCMAKE_INSTALL_PREFIX=/N/project/MSB_Project/E3SMv2.1_Josh_Project/E3SMv2.1_scripts/v2.1.WCYCLSSP370_20180201-20180401_12n32p_trial_05/build/intel/mpich/nodebug/nothreads/mct /N/project/MSB_Project/E3SMv2.1_original/E3SM/externals/kokkos

CMake Error: Unknown argument --cxxflags=-include stdint.h
CMake Error: Run 'cmake --help' for all supported options.
ERROR: CMake Error: Unknown argument --cxxflags=-include stdint.h
CMake Error: Run 'cmake --help' for all supported options

I've looked at my E3SM/externals/kokkos/cmake/intel.cmake, and it looks like:

FUNCTION(kokkos_set_intel_flags full_standard int_standard)
  STRING(APPEND CXXFLAGS " -include stdint.h")
  STRING(TOLOWER ${full_standard} FULL_LC_STANDARD)
  STRING(TOLOWER ${int_standard} INT_LC_STANDARD)
  # The following three blocks of code were copied from
  # /Modules/Compiler/Intel-CXX.cmake from CMake 3.18.1 and then modified.
  IF(CMAKE_CXX_SIMULATE_ID STREQUAL MSVC)
    SET(_std -Qstd)
    SET(_ext c++)
  ELSE()
    SET(_std -std)
    SET(_ext gnu++)
  ENDIF()
  SET(KOKKOS_CXX_STANDARD_FLAG             "${_std}=c++${FULL_LC_STANDARD}" PARENT_SCOPE)
  SET(KOKKOS_CXX_INTERMDIATE_STANDARD_FLAG "${_std}=${_ext}${INT_LC_STANDARD}" PARENT_SCOPE)
ENDFUNCTION()

You'll notice there's a space before the -include which makes me think the error message is referring to a different place where I set CXXFLAGS. But I can't find anywhere in the source code or my cime directory where the string "-include stdint.h" is used.

Any help would be greatly appreciated. Thanks

[bartgol]

The Macros.make file in your case dir must contain that odd flag in the KOKKOS_OPTIONS settings. This must come from the cmake_macro/compiler_mach.cmake file. You could try to hack share/build/buildlib.kokkos to print a bit more info regarding the Macros.make file content...

[pgoddard08]

Hi, thank you for your help.

You are correct. In the case dir/case_scripts the Macros.make has the line KOKKOS_OPTIONS := --with-serial --cxxflags='-include stdint.h'

However, I'm not sure I follow the rest of your suggestion. Would you mind explaining further where I can change this flag? Thanks!

[bartgol]

Forget the last part of my post, it makes no sense. @jgfouca may know how Macros.make gets created.

Btw, since this is v2.1, things may be quite different from current master, so it's a bit hard to come up with good debugging ideas...

[rljacob]

What case were you trying to build and what version of the intel compiler are you using?

[pgoddard08]

Hi,

I was trying to build from compset WCYCLSSP370 and I am using intel 2025.2.

I did find in .cime/intel_BigRed200.cmake where I was setting those options:
set(KOKKOS_OPTIONS "--with-serial --cxxflags='-include stdint.h'")

However, if I comment out this line, I get a whole list of errors during the build.

Just FYI, I run v2.0 just fine. It's only with v2.1 that I get this KOKKOS error.

Thanks!

[rljacob]

We test 2.1 with ifort v20.0.0. The versions of kokkos look to be the same from 2.0 to 2.1. What is your cmake version?

[pgoddard08]

Hi - I am using cmake version 4.1.0.

The suggestion by @jgfouca below worked for me.

[jgfouca]

@pgoddard08 , try this

string(APPEND KOKKOS_OPTIONS " -DKokkos_ENABLE_SERIAL=On -DCMAKE_CXX_FLAGS='-include stdint.h'")

[pgoddard08]

Hi,

Which file should I add that to,
E3SM/externals/kokkos/cmake/intel.cmake
or
.cime/intel_BigRed200.cmake ?

Do I keep set(KOKKOS_OPTIONS "--with-serial --cxxflags='-include stdint.h'") in .cime/intel_BigRed200.cmake ? Because if I comment out this line of code, I get all sorts of errors.

Thanks!

[jgfouca]

You should take the line I gave you and replace the one in BigRed.cmake that sets the KOKKOS_OPTIONS.

[pgoddard08]

Thanks - that worked!!