[patch] gromacs-2021-cuda-detection.patch

gromacs-2021-cuda-detection.patch (text/plain), 21.34 KB, created by Pacho Ramos on 2023-03-07 17:10:37 UTC

--- gromacs-2021.7/cmake/gmxManageNvccConfig.cmake	2023-01-31 12:45:45.000000000 +0100
+++ gromacs-2022.5/cmake/gmxManageNvccConfig.cmake	2023-02-03 12:53:34.000000000 +0100
@@ -1,11 +1,9 @@
 #
 # This file is part of the GROMACS molecular simulation package.
 #
-# Copyright (c) 2012,2013,2014,2015,2016 by the GROMACS development team.
-# Copyright (c) 2017,2018,2019,2020,2021, by the GROMACS development team, led by
-# Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
-# and including many others, as listed in the AUTHORS file in the
-# top-level source directory and at http://www.gromacs.org.
+# Copyright 2012- The GROMACS Authors
+# and the project initiators Erik Lindahl, Berk Hess and David van der Spoel.
+# Consult the AUTHORS/COPYING files and https://www.gromacs.org for details.
 #
 # GROMACS is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public License
@@ -19,7 +17,7 @@
 #
 # You should have received a copy of the GNU Lesser General Public
 # License along with GROMACS; if not, see
-# http://www.gnu.org/licenses, or write to the Free Software Foundation,
+# https://www.gnu.org/licenses, or write to the Free Software Foundation,
 # Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
 #
 # If you want to redistribute modifications to GROMACS, please
@@ -28,10 +26,10 @@
 # consider code for inclusion in the official distribution, but
 # derived work must not be called official GROMACS. Details are found
 # in the README & COPYING files - if they are missing, get the
-# official version at http://www.gromacs.org.
+# official version at https://www.gromacs.org.
 #
 # To help us fund GROMACS development, we humbly ask that you cite
-# the research papers on the package. Check out http://www.gromacs.org.
+# the research papers on the package. Check out https://www.gromacs.org.
 
 # Manage CUDA nvcc compilation configuration, try to be smart to ease the users'
 # pain as much as possible:
@@ -51,7 +49,7 @@
 # glibc source shows that _FORCE_INLINES is only used in this string.h
 # feature and performance of memcpy variants is unimportant for CUDA
 # code in GROMACS. So this workaround is good enough to keep problems
-# away from users installing GROMACS. See Issue #1942.
+# away from users installing GROMACS. See Issue #1982.
 function(work_around_glibc_2_23)
     try_compile(IS_GLIBC_2_23_OR_HIGHER ${CMAKE_BINARY_DIR} ${CMAKE_SOURCE_DIR}/cmake/TestGlibcVersion.cpp)
     if(IS_GLIBC_2_23_OR_HIGHER)
@@ -83,67 +81,158 @@
     mark_as_advanced(CUDA_HOST_COMPILER CUDA_HOST_COMPILER_OPTIONS)
 endif()
 
+# We would like to be helpful and reject the host compiler with a
+# clear error message at configure time, rather than let nvcc
+# later reject the host compiler as not supported when the first
+# CUDA source file is built. We've implemented that for current
+# nvcc running on Unix-like systems, but e.g. changes to nvcc
+# will further affect the limited portability of this checking
+# code. Set the CMake variable GMX_NVCC_WORKS on if you want to
+# bypass this check.
+if((_cuda_nvcc_executable_or_flags_changed OR CUDA_HOST_COMPILER_CHANGED OR NOT GMX_NVCC_WORKS) AND NOT WIN32)
+    message(STATUS "Check for working NVCC/C++ compiler combination with nvcc '${CUDA_NVCC_EXECUTABLE}'")
+    execute_process(COMMAND ${CUDA_NVCC_EXECUTABLE} --compiler-bindir=${CUDA_HOST_COMPILER} -c ${CUDA_NVCC_FLAGS} ${CUDA_NVCC_FLAGS_${_build_type}} ${CMAKE_SOURCE_DIR}/cmake/TestCUDA.cu
+        RESULT_VARIABLE _cuda_test_res
+        OUTPUT_VARIABLE _cuda_test_out
+        ERROR_VARIABLE  _cuda_test_err
+        OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+    if(${_cuda_test_res})
+        message(STATUS "Check for working NVCC/C compiler combination - broken")
+        message(STATUS "${CUDA_NVCC_EXECUTABLE} standard output: '${_cuda_test_out}'")
+        message(STATUS "${CUDA_NVCC_EXECUTABLE} standard error:  '${_cuda_test_err}'")
+        if(${_cuda_test_err} MATCHES "nsupported")
+            message(FATAL_ERROR "NVCC/C++ compiler combination does not seem to be supported. CUDA frequently does not support the latest versions of the host compiler, so you might want to try an earlier C++ compiler version and make sure your CUDA compiler and driver are as recent as possible. Set the GMX_NVCC_WORKS CMake cache variable to bypass this check if you know what you are doing.")
+        elseif(CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_EQUAL 11.2 AND CUDA_VERSION VERSION_GREATER 11.4 AND CUDA_VERSION VERSION_LESS 11.7) # Issue #4574, #4641
+            # Above, we should be checking for VERSION_LESS 11.6.2, but CUDA_VERSION is only "major.minor"
+            message(FATAL_ERROR "CUDA versions 11.5-11.6.1 are known to be incompatible with some GCC 11.x. Use a different GCC or update your CUDA installation to at least CUDA 11.6.2")
+        else()
+            message(FATAL_ERROR "CUDA compiler does not seem to be functional or is not compatible with the host compiler. Set the GMX_NVCC_WORKS CMake cache variable to bypass this check if you know what you are doing.")
+        endif()
+    elseif(NOT GMX_CUDA_TEST_COMPILER_QUIETLY)
+        message(STATUS "Check for working NVCC/C++ compiler combination - works")
+        set(GMX_NVCC_WORKS TRUE CACHE INTERNAL "Nvcc can compile a trivial test program")
+    endif()
+endif() # GMX_CHECK_NVCC
+
+# Tests a single flag to use with nvcc.
+#
+# If the flags are accepted, they are appended to the variable named
+# in the first argument. The cache variable named in the second
+# argument is used to avoid rerunning the check in future invocations
+# of cmake. The list of flags to check follows these two required
+# arguments.
+#
+# Note that a space-separated string of flags, or a flag-value pair
+# separated by spaces will not work. Use the single-argument forms
+# accepted by nvcc, like "--arg=value".
+#
+# As this code is not yet tested on Windows, it always accepts the
+# flags in that case.
+function(gmx_add_nvcc_flag_if_supported _output_variable_name_to_append_to _flags_cache_variable_name)
+    # If the check has already been run, do not re-run it
+    if (NOT ${_flags_cache_variable_name} AND NOT WIN32)
+        message(STATUS "Checking if nvcc accepts flags ${ARGN}")
+        # See detailed comment about gcc 7 below
+        if (CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 8)
+            set(_cache_variable_value TRUE)
+            message(STATUS "Checking if nvcc accepts flags ${ARGN} - Assuming success when using gcc 7")
+        else()
+            if(NOT(CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 11))
+              set(CCBIN "--compiler-bindir=${CUDA_HOST_COMPILER}")
+            endif()
+            execute_process(
+                COMMAND ${CUDA_NVCC_EXECUTABLE} ${ARGN} ${CCBIN} "${CMAKE_SOURCE_DIR}/cmake/TestCUDA.cu"
+                RESULT_VARIABLE _cuda_success
+                OUTPUT_QUIET
+                ERROR_QUIET
+                )
+            # Convert the success value to a boolean and report status
+            if (_cuda_success EQUAL 0)
+                set(_cache_variable_value TRUE)
+                message(STATUS "Checking if nvcc accepts flags ${ARGN} - Success")
+            else()
+                set(_cache_variable_value FALSE)
+                message(STATUS "Checking if nvcc accepts flags ${ARGN} - Failed")
+            endif()
+        endif()
+        set(${_flags_cache_variable_name} ${_cache_variable_value} CACHE BOOL "Whether NVCC supports flag(s) ${ARGN}")
+    endif()
+    # Append the flags to the output variable if they have been tested to work
+    if (${_flags_cache_variable_name} OR WIN32)
+        list(APPEND ${_output_variable_name_to_append_to} ${ARGN})
+        set(${_output_variable_name_to_append_to} ${${_output_variable_name_to_append_to}} PARENT_SCOPE)
+    endif()
+endfunction()
+
+# Versions of gcc 7 have differing behavior when executing
+#
+#  nvcc $args --compiler-bindir=gcc TestCUDA.cu
+#
+# and would need e.g. adding -lstdc++ to the command line so that
+# linking of a C++/CUDA object by the C-compiler flavor of gcc works.
+# This means we can't reliably test compiler flags in this case
+# without risking creating other problems. Instead we assume (above)
+# that all compiler flags will work, and issue this warning.
+# We also want to skip this warning during GROMACS CI testing.
+if (CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 8
+    AND NOT DEFINED ENV{GITLAB_CI})
+    message(WARNING "You are using gcc version 7 with the CUDA compiler nvcc. GROMACS cannot reliably test compiler arguments for this combination, so if you later experience errors in building GROMACS, please use a more recent version of gcc.")
+endif()
+
 # If any of these manual override variables for target CUDA GPU architectures
 # or virtual architecture is set, parse the values and assemble the nvcc
 # command line for these. Otherwise use our defaults.
 # Note that the manual override variables require a semicolon separating
 # architecture codes.
+set(GMX_CUDA_NVCC_GENCODE_FLAGS)
 if (GMX_CUDA_TARGET_SM OR GMX_CUDA_TARGET_COMPUTE)
-    set(GMX_CUDA_NVCC_GENCODE_FLAGS)
     set(_target_sm_list ${GMX_CUDA_TARGET_SM})
     foreach(_target ${_target_sm_list})
-        list(APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_${_target},code=sm_${_target}")
+        gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_${_target} "--generate-code=arch=compute_${_target},code=sm_${_target}")
+        if (NOT NVCC_HAS_GENCODE_COMPUTE_AND_SM_${_target} AND NOT WIN32)
+            message(FATAL_ERROR "Your choice of ${_target} in GMX_CUDA_TARGET_SM was not accepted by nvcc, please choose a target that it accepts")
+        endif()
     endforeach()
     set(_target_compute_list ${GMX_CUDA_TARGET_COMPUTE})
     foreach(_target ${_target_compute_list})
-        list(APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_${_target},code=compute_${_target}")
+        gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_${_target} --generate-code=arch=compute_${_target},code=compute_${_target})
+        if (NOT NVCC_HAS_GENCODE_COMPUTE_${_target} AND NOT WIN32)
+            message(FATAL_ERROR "Your choice of ${_target} in GMX_CUDA_TARGET_COMPUTE was not accepted by nvcc, please choose a target that it accepts")
+        endif()
     endforeach()
 else()
     # Set the CUDA GPU architectures to compile for:
-    # - with CUDA >=9.0         CC 7.0 is supported and CC 2.0 is no longer supported
-    #     => compile sm_30, sm_35, sm_37, sm_50, sm_52, sm_60, sm_61, sm_70 SASS, and compute_35, compute_70 PTX
-    # - with CUDA >=10.0        CC 7.5 is supported
-    #     => compile sm_30, sm_35, sm_37, sm_50, sm_52, sm_60, sm_61, sm_70, sm_75 SASS, and compute_35, compute_75 PTX
     # - with CUDA >=11.0        CC 8.0 is supported
     #     => compile sm_35, sm_37, sm_50, sm_52, sm_60, sm_61, sm_70, sm_75, sm_80 SASS, and compute_35, compute_80 PTX
 
     # First add flags that trigger SASS (binary) code generation for physical arch
-    if(CUDA_VERSION VERSION_LESS "11.0")
-        list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_30,code=sm_30")
-    endif()
-    list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_35,code=sm_35")
-    list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_37,code=sm_37")
-    list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_50,code=sm_50")
-    list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_52,code=sm_52")
-    list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_60,code=sm_60")
-    list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_61,code=sm_61")
-    list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_70,code=sm_70")
-    if(NOT CUDA_VERSION VERSION_LESS "10.0")
-        list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_75,code=sm_75")
-    endif()
-    if(NOT CUDA_VERSION VERSION_LESS "11.0")
-        list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_80,code=sm_80")
-        # Requesting sm or compute 35, 37, or 50 triggers deprecation messages with
-        # nvcc 11.0, which we need to suppress for use in CI
-        list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-Wno-deprecated-gpu-targets")
-    endif()
-    if(NOT CUDA_VERSION VERSION_LESS "11.1")
-        list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_86,code=sm_86")
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_35 --generate-code=arch=compute_35,code=sm_35)
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_37 --generate-code=arch=compute_37,code=sm_37)
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_50 --generate-code=arch=compute_50,code=sm_50)
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_52 --generate-code=arch=compute_52,code=sm_52)
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_60 --generate-code=arch=compute_60,code=sm_60)
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_61 --generate-code=arch=compute_61,code=sm_61)
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_70 --generate-code=arch=compute_70,code=sm_70)
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_75 --generate-code=arch=compute_75,code=sm_75)
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_80 --generate-code=arch=compute_80,code=sm_80)
+    # Don't attempt to add newest architectures with old GNU compiler, to avoid issues in CI
+    # related to being unable to test which flags are supported
+    if (NOT (CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 8))
+        gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_86 --generate-code=arch=compute_86,code=sm_86)
+        gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_89 --generate-code=arch=compute_89,code=sm_89)
+        gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_AND_SM_90 --generate-code=arch=compute_90,code=sm_90)
     endif()
+    # Requesting sm or compute 35, 37, or 50 triggers deprecation messages with
+    # nvcc 11.0, which we need to suppress for use in CI
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_WARNING_NO_DEPRECATED_GPU_TARGETS -Wno-deprecated-gpu-targets)
 
     # Next add flags that trigger PTX code generation for the
     # newest supported virtual arch that's useful to JIT to future architectures
     # as well as an older one suitable for JIT-ing to any rare intermediate arch
     # (like that of Jetson / Drive PX devices)
-    list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_35,code=compute_35")
-    if(CUDA_VERSION VERSION_LESS "11.0")
-        list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_32,code=compute_32")
-    else()
-        list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_53,code=compute_53")
-    endif()
-    if(NOT CUDA_VERSION VERSION_LESS "11.0")
-        list (APPEND GMX_CUDA_NVCC_GENCODE_FLAGS "-gencode;arch=compute_80,code=compute_80")
-    endif()
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_53 --generate-code=arch=compute_53,code=sm_53)
+    gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_GENCODE_FLAGS NVCC_HAS_GENCODE_COMPUTE_80 --generate-code=arch=compute_80,code=sm_80)
 endif()
 
 if (GMX_CUDA_TARGET_SM)
@@ -158,27 +247,20 @@
 # FindCUDA.cmake is unaware of the mechanism used by cmake to embed
 # the compiler flag for the required C++ standard in the generated
 # build files, so we have to pass it ourselves
-if (CUDA_VERSION VERSION_LESS 11.0)
-    # CUDA doesn't formally support C++17 until version 11.0, so for
-    # now host-side code that compiles with CUDA is restricted to
-    # C++14. This needs to be expressed formally for older CUDA
-    # version.
+
+# gcc-7 pre-dated C++17, so uses the -std=c++1z compiler flag for it,
+# which modern nvcc does not recognize. So we work around that by
+# compiling in C++14 mode. Clang doesn't have this problem because nvcc
+# only supports version of clang that already understood -std=c++17
+if (CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 8)
     list(APPEND GMX_CUDA_NVCC_FLAGS "${CMAKE_CXX14_STANDARD_COMPILE_OPTION}")
 else()
-    # gcc-7 pre-dated C++17, so uses the -std=c++1z compiler flag for it,
-    # which modern nvcc does not recognize. So we work around that by
-    # compiling in C++14 mode. Clang doesn't have this problem because nvcc
-    # only supports version of clang that already understood -std=c++17
-    if (CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 8)
-        list(APPEND GMX_CUDA_NVCC_FLAGS "${CMAKE_CXX14_STANDARD_COMPILE_OPTION}")
-    else()
-        list(APPEND GMX_CUDA_NVCC_FLAGS "${CMAKE_CXX17_STANDARD_COMPILE_OPTION}")
-    endif()
+    list(APPEND GMX_CUDA_NVCC_FLAGS "${CMAKE_CXX17_STANDARD_COMPILE_OPTION}")
 endif()
 
 # assemble the CUDA flags
 list(APPEND GMX_CUDA_NVCC_FLAGS "${GMX_CUDA_NVCC_GENCODE_FLAGS}")
-list(APPEND GMX_CUDA_NVCC_FLAGS "-use_fast_math")
+gmx_add_nvcc_flag_if_supported(GMX_CUDA_NVCC_FLAGS NVCC_HAS_USE_FAST_MATH -use_fast_math)
 
 # assemble the CUDA host compiler flags
 list(APPEND GMX_CUDA_NVCC_FLAGS "${CUDA_HOST_COMPILER_OPTIONS}")
@@ -187,12 +269,18 @@
     # CUDA header cuda_runtime_api.h in at least CUDA 10.1 uses 0
     # where nullptr would be preferable. GROMACS can't fix these, so
     # must suppress them.
-    GMX_TEST_CXXFLAG(CXXFLAGS_NO_ZERO_AS_NULL_POINTER_CONSTANT "-Wno-zero-as-null-pointer-constant" NVCC_CLANG_SUPPRESSIONS_CXXFLAGS)
+    GMX_TEST_CXXFLAG(HAS_WARNING_NO_ZERO_AS_NULL_POINTER_CONSTANT "-Wno-zero-as-null-pointer-constant" NVCC_CLANG_SUPPRESSIONS_CXXFLAGS)
 
     # CUDA header crt/math_functions.h in at least CUDA 10.x and 11.1
     # used throw() specifications that are deprecated in more recent
     # C++ versions. GROMACS can't fix these, so must suppress them.
-    GMX_TEST_CXXFLAG(CXXFLAGS_NO_DEPRECATED_DYNAMIC_EXCEPTION_SPEC "-Wno-deprecated-dynamic-exception-spec" NVCC_CLANG_SUPPRESSIONS_CXXFLAGS)
+    GMX_TEST_CXXFLAG(HAS_WARNING_NO_DEPRECATED_DYNAMIC_EXCEPTION_SPEC "-Wno-deprecated-dynamic-exception-spec" NVCC_CLANG_SUPPRESSIONS_CXXFLAGS)
+
+    # CUDA headers cuda_runtime.h and channel_descriptor.h in at least
+    # CUDA 11.0 uses many C-style casts, which are ncessary for this
+    # header to work for C. GROMACS can't fix these, so must suppress
+    # the warnings they generate
+    GMX_TEST_CXXFLAG(HAS_WARNING_NO_OLD_STYLE_CAST "-Wno-old-style-cast" NVCC_CLANG_SUPPRESSIONS_CXXFLAGS)
 
     # Add these flags to those used for the host compiler. The
     # "-Xcompiler" prefix directs nvcc to only use them for host
@@ -205,37 +293,6 @@
 string(TOUPPER "${CMAKE_BUILD_TYPE}" _build_type)
 gmx_check_if_changed(_cuda_nvcc_executable_or_flags_changed CUDA_NVCC_EXECUTABLE CUDA_NVCC_FLAGS CUDA_NVCC_FLAGS_${_build_type})
 
-# We would like to be helpful and reject the host compiler with a
-# clear error message at configure time, rather than let nvcc
-# later reject the host compiler as not supported when the first
-# CUDA source file is built. We've implemented that for current
-# nvcc running on Unix-like systems, but e.g. changes to nvcc
-# will further affect the limited portability of this checking
-# code. Set the CMake variable GMX_NVCC_WORKS on if you want to
-# bypass this check.
-if((_cuda_nvcc_executable_or_flags_changed OR CUDA_HOST_COMPILER_CHANGED OR NOT GMX_NVCC_WORKS) AND NOT WIN32)
-    message(STATUS "Check for working NVCC/C++ compiler combination with nvcc '${CUDA_NVCC_EXECUTABLE}'")
-    execute_process(COMMAND ${CUDA_NVCC_EXECUTABLE} -ccbin ${CUDA_HOST_COMPILER} -c ${CUDA_NVCC_FLAGS} ${CUDA_NVCC_FLAGS_${_build_type}} ${CMAKE_SOURCE_DIR}/cmake/TestCUDA.cu
-        RESULT_VARIABLE _cuda_test_res
-        OUTPUT_VARIABLE _cuda_test_out
-        ERROR_VARIABLE  _cuda_test_err
-        OUTPUT_STRIP_TRAILING_WHITESPACE)
-
-    if(${_cuda_test_res})
-        message(STATUS "Check for working NVCC/C compiler combination - broken")
-        message(STATUS "${CUDA_NVCC_EXECUTABLE} standard output: '${_cuda_test_out}'")
-        message(STATUS "${CUDA_NVCC_EXECUTABLE} standard error:  '${_cuda_test_err}'")
-        if(${_cuda_test_err} MATCHES "nsupported")
-            message(FATAL_ERROR "NVCC/C++ compiler combination does not seem to be supported. CUDA frequently does not support the latest versions of the host compiler, so you might want to try an earlier C++ compiler version and make sure your CUDA compiler and driver are as recent as possible.")
-        else()
-            message(FATAL_ERROR "CUDA compiler does not seem to be functional.")
-        endif()
-    elseif(NOT GMX_CUDA_TEST_COMPILER_QUIETLY)
-        message(STATUS "Check for working NVCC/C++ compiler combination - works")
-        set(GMX_NVCC_WORKS TRUE CACHE INTERNAL "Nvcc can compile a trivial test program")
-    endif()
-endif() # GMX_CHECK_NVCC
-
 
 # The flags are set as local variables which shadow the cache variables. The cache variables
 # (can be set by the user) are appended. This is done in a macro to set the flags when all