Merge branch 'backport-cuda-default-runtime' into cuda-default-runtime

Help/command/try_compile.rst

@@ -135,6 +135,7 @@ If set, the following variables are passed in to the generated
 try_compile CMakeLists.txt to initialize compile target properties with
 default values:
 
+* :variable:`CMAKE_CUDA_RUNTIME_LIBRARY`
 * :variable:`CMAKE_ENABLE_EXPORTS`
 * :variable:`CMAKE_LINK_SEARCH_START_STATIC`
 * :variable:`CMAKE_LINK_SEARCH_END_STATIC`

Help/prop_tgt/CUDA_RUNTIME_LIBRARY.rst

@@ -10,8 +10,8 @@ The allowed case insensitive values are:
 Contents of ``CUDA_RUNTIME_LIBRARY`` may use
 :manual:`generator expressions <cmake-generator-expressions(7)>`.
 
-If this property is not set then CMake uses the default value
-``Static`` to select the CUDA runtime library.
+If that property is not set then CMake uses an appropriate default
+value based on the compiler to select the CUDA runtime library.
 
 .. note::
 

Help/variable/CMAKE_CUDA_RUNTIME_LIBRARY.rst

@@ -1,7 +1,7 @@
 CMAKE_CUDA_RUNTIME_LIBRARY
 --------------------------
 
-Select the CUDA runtime library for use by compilers targeting the MSVC ABI.
+Select the CUDA runtime library for use when compiling and linking CUDA.
 This variable is used to initialize the :prop_tgt:`CUDA_RUNTIME_LIBRARY`
 property on all targets as they are created.
 
@@ -14,7 +14,8 @@ Contents of ``CMAKE_CUDA_RUNTIME_LIBRARY`` may use
 
 If this variable is not set then the :prop_tgt:`CUDA_RUNTIME_LIBRARY` target
 property will not be set automatically.  If that property is not set then
-CMake uses the default value ``Static`` to select the CUDA runtime library.
+CMake uses an appropriate default value based on the compiler to select the
+CUDA runtime library.
 
 .. note::
 

Modules/CMakeCUDACompiler.cmake.in

@@ -54,6 +54,8 @@ set(CMAKE_CUDA_IMPLICIT_LINK_LIBRARIES "@CMAKE_CUDA_IMPLICIT_LINK_LIBRARIES@")
 set(CMAKE_CUDA_IMPLICIT_LINK_DIRECTORIES "@CMAKE_CUDA_IMPLICIT_LINK_DIRECTORIES@")
 set(CMAKE_CUDA_IMPLICIT_LINK_FRAMEWORK_DIRECTORIES "@CMAKE_CUDA_IMPLICIT_LINK_FRAMEWORK_DIRECTORIES@")
 
+@_SET_CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT@
+
 set(CMAKE_LINKER "@CMAKE_LINKER@")
 set(CMAKE_AR "@CMAKE_AR@")
 set(CMAKE_MT "@CMAKE_MT@")

Modules/CMakeDetermineCUDACompiler.cmake

@@ -112,6 +112,20 @@ if(${CMAKE_GENERATOR} MATCHES "Visual Studio")
   set(CMAKE_CUDA_HOST_IMPLICIT_LINK_LIBRARIES "")
   set(CMAKE_CUDA_HOST_IMPLICIT_LINK_DIRECTORIES "")
   set(CMAKE_CUDA_HOST_IMPLICIT_LINK_FRAMEWORK_DIRECTORIES "")
+
+  # We do not currently detect CMAKE_CUDA_HOST_IMPLICIT_LINK_LIBRARIES but we
+  # do need to detect CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT from the compiler by
+  # looking at which cudart library exists in the implicit link libraries passed
+  # to the host linker.
+  if(CMAKE_CUDA_COMPILER_PRODUCED_OUTPUT MATCHES "link\\.exe [^\n]*cudart_static\\.lib")
+    set(CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT "STATIC")
+  elseif(CMAKE_CUDA_COMPILER_PRODUCED_OUTPUT MATCHES "link\\.exe [^\n]*cudart\\.lib")
+    set(CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT "SHARED")
+  else()
+    set(CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT "NONE")
+  endif()
+  set(_SET_CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT
+    "set(CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT \"${CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT}\")")
 elseif(CMAKE_CUDA_COMPILER_ID STREQUAL "Clang")
   # Parse default CUDA architecture.
   if(NOT CMAKE_CUDA_ARCHITECTURES)
@@ -232,6 +246,20 @@ elseif(CMAKE_CUDA_COMPILER_ID STREQUAL "NVIDIA")
                                    log
                                    "${CMAKE_CUDA_IMPLICIT_OBJECT_REGEX}")
 
+    # Detect CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT from the compiler by looking at which
+    # cudart library exists in the implicit link libraries passed to the host linker.
+    # This is required when a project sets the cuda runtime library as part of the
+    # initial flags.
+    if(";${CMAKE_CUDA_HOST_IMPLICIT_LINK_LIBRARIES};" MATCHES [[;cudart_static(\.lib)?;]])
+      set(CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT "STATIC")
+    elseif(";${CMAKE_CUDA_HOST_IMPLICIT_LINK_LIBRARIES};" MATCHES [[;cudart(\.lib)?;]])
+      set(CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT "SHARED")
+    else()
+      set(CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT "NONE")
+    endif()
+    set(_SET_CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT
+      "set(CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT \"${CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT}\")")
+
     file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
       "Parsed CUDA nvcc implicit link information from above output:\n${_nvcc_log}\n${log}\n\n")
   else()

Modules/CMakeDetermineCompilerId.cmake

@@ -381,7 +381,11 @@ Id flags: ${testflags} ${CMAKE_${lang}_COMPILER_ID_FLAGS_ALWAYS}
       if(CMAKE_VS_PLATFORM_NAME STREQUAL x64)
         set(id_ItemDefinitionGroup_entry "<CudaCompile><TargetMachinePlatform>64</TargetMachinePlatform><AdditionalOptions>%(AdditionalOptions)-v</AdditionalOptions></CudaCompile>")
       endif()
-      set(id_Link_AdditionalDependencies "<AdditionalDependencies>cudart.lib</AdditionalDependencies>")
+      if(CMAKE_CUDA_FLAGS MATCHES "(^| )-cudart +shared( |$)")
+        set(id_Link_AdditionalDependencies "<AdditionalDependencies>cudart.lib</AdditionalDependencies>")
+      else()
+        set(id_Link_AdditionalDependencies "<AdditionalDependencies>cudart_static.lib</AdditionalDependencies>")
+      endif()
     endif()
     configure_file(${CMAKE_ROOT}/Modules/CompilerId/VS-${v}.${ext}.in
       ${id_dir}/CompilerId${lang}.${ext} @ONLY)

Modules/Compiler/NVIDIA-CUDA.cmake

@@ -59,7 +59,6 @@ set(CMAKE_CUDA_DEVICE_COMPILER_WRAPPER_FLAG_SEP ",")
 set(CMAKE_CUDA_DEVICE_LINKER_WRAPPER_FLAG "-Xlinker=")
 set(CMAKE_CUDA_DEVICE_LINKER_WRAPPER_FLAG_SEP ",")
 
-set(CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT "STATIC")
 set(CMAKE_CUDA_RUNTIME_LIBRARY_LINK_OPTIONS_STATIC  "cudadevrt;cudart_static")
 set(CMAKE_CUDA_RUNTIME_LIBRARY_LINK_OPTIONS_SHARED  "cudadevrt;cudart")
 set(CMAKE_CUDA_RUNTIME_LIBRARY_LINK_OPTIONS_NONE    "")

Modules/Platform/Windows-NVIDIA-CUDA.cmake

@@ -69,7 +69,6 @@ else()
 endif()
 unset(_cmp0092)
 
-set(CMAKE_CUDA_RUNTIME_LIBRARY_DEFAULT "STATIC")
 set(CMAKE_CUDA_RUNTIME_LIBRARY_LINK_OPTIONS_STATIC  "cudadevrt;cudart_static")
 set(CMAKE_CUDA_RUNTIME_LIBRARY_LINK_OPTIONS_SHARED  "cudadevrt;cudart")
 set(CMAKE_CUDA_RUNTIME_LIBRARY_LINK_OPTIONS_NONE    "")

Source/cmCoreTryCompile.cxx

@@ -44,6 +44,8 @@ static std::string const kCMAKE_CUDA_ARCHITECTURES =
   "CMAKE_CUDA_ARCHITECTURES";
 static std::string const kCMAKE_CUDA_COMPILER_TARGET =
   "CMAKE_CUDA_COMPILER_TARGET";
+static std::string const kCMAKE_CUDA_RUNTIME_LIBRARY =
+  "CMAKE_CUDA_RUNTIME_LIBRARY";
 static std::string const kCMAKE_ENABLE_EXPORTS = "CMAKE_ENABLE_EXPORTS";
 static std::string const kCMAKE_LINK_SEARCH_END_STATIC =
   "CMAKE_LINK_SEARCH_END_STATIC";
@@ -717,6 +719,7 @@ int cmCoreTryCompile::TryCompileCode(std::vector<std::string> const& argv,
       vars.insert(kCMAKE_CXX_COMPILER_TARGET);
       vars.insert(kCMAKE_CUDA_ARCHITECTURES);
       vars.insert(kCMAKE_CUDA_COMPILER_TARGET);
+      vars.insert(kCMAKE_CUDA_RUNTIME_LIBRARY);
       vars.insert(kCMAKE_ENABLE_EXPORTS);
       vars.insert(kCMAKE_LINK_SEARCH_END_STATIC);
       vars.insert(kCMAKE_LINK_SEARCH_START_STATIC);

Tests/CudaOnly/CMakeLists.txt

@@ -9,6 +9,8 @@ ADD_TEST_MACRO(CudaOnly.Toolkit CudaOnlyToolkit)
 ADD_TEST_MACRO(CudaOnly.WithDefs CudaOnlyWithDefs)
 
 if(CMake_TEST_CUDA AND NOT CMake_TEST_CUDA STREQUAL "Clang")
+  ADD_TEST_MACRO(CudaOnly.SharedRuntimeViaCUDAFlags CudaOnlySharedRuntimeViaCUDAFlags)
+
   # Separable compilation is currently only supported on NVCC. Disable tests
   # using it for other compilers.
   ADD_TEST_MACRO(CudaOnly.CircularLinkLine CudaOnlyCircularLinkLine)

Tests/CudaOnly/SharedRuntimeViaCUDAFlags/CMakeLists.txt

@@ -0,0 +1,15 @@
+cmake_minimum_required(VERSION 3.17)
+project(SharedRuntimeViaCUDAFlags NONE)
+
+set(CMAKE_CUDA_FLAGS "")
+string(APPEND CMAKE_CUDA_FLAGS "-cudart shared")
+
+enable_language(CUDA)
+
+add_executable(CudaOnlySharedRuntimeViaCUDAFlags main.cu)
+
+if(UNIX)
+  # Help the shared cuda runtime find libcudart as it is not located
+  # in a default system searched location
+  set_property(TARGET CudaOnlySharedRuntimeViaCUDAFlags PROPERTY BUILD_RPATH ${CMAKE_CUDA_IMPLICIT_LINK_DIRECTORIES})
+endif()

Tests/CudaOnly/SharedRuntimeViaCUDAFlags/main.cu

@@ -0,0 +1,5 @@
+
+int main()
+{
+  return 0;
+}