WIP Enable JIT compilation of CUDA code with root.exe

[LukasBreitwieser]

Working prototype of JIT compilation of CUDA code with bin/root.exe using the following test script:

.rawInput 1
__global__ void Kernel(int *out) { *out = 42; }
.rawInput 0
int *deviceOutput;
int hostOutput = 0;
cudaMalloc((void **) &deviceOutput, sizeof(int));
Kernel<<<1,1>>>(deviceOutput);
cudaGetLastError();
cudaDeviceSynchronize();
cudaMemcpy(&hostOutput, deviceOutput, sizeof(int), cudaMemcpyDeviceToHost);
std::cout << "Test " << (hostOutput == 42 ? "passed" : "FAILED") << std::endl;
.q

Remaining Issues

ROOT build without cpp modules

libcomplexDict.rootmap issue

Search for the root cause of the following error:

cling-ptx: Forward declarations from /home/lukas/sft/ws/root-project/build/Debug-no-modules/lib/libcomplexDict.rootmap:2:19: error: explicit specialization of undeclared template 
class 'complex'
template <> class complex<float>;
                  ^      ~~~~~~~
cling-ptx: Forward declarations from /home/lukas/sft/ws/root-project/build/Debug-no-modules/lib/libcomplexDict.rootmap:3:19: error: explicit specialization of non-template class '
complex'
template <> class complex<double>;

Quick fix: manually remove the following lines from libcomplexDict.rootmap

template <> class complex<float>;
template <> class complex<double>;
template <typename T> class _root_std_complex;

TClass error:

Processing hsimple.C...
cling-ptx: In file included from input_line_8:1:
In file included from /home/lukas/sft/ws/root-project/build/Debug-no-modules/include/TFile.h:28:
In file included from /home/lukas/sft/ws/root-project/build/Debug-no-modules/include/TDirectoryFile.h:25:
In file included from /home/lukas/sft/ws/root-project/build/Debug-no-modules/include/TDirectory.h:24:
In file included from /home/lukas/sft/ws/root-project/build/Debug-no-modules/include/TNamed.h:25:
In file included from /home/lukas/sft/ws/root-project/build/Debug-no-modules/include/TObject.h:18:
/home/lukas/sft/ws/root-project/build/Debug-no-modules/include/TStorage.h:85:4: error: incomplete type 'TClass' named in nested name specifier
   ClassDef(TStorage,0)  //Storage manager class

ROOT build with cpp modules

Fix wrong order of including headers:

cling: In file included from <built-in>:1:
In file included from /home/lukas/sft/ws/root-project/build/Debug/etc//cling/lib/clang/18/include/__clang_cuda_runtime_wrapper.h:157:
/home/lukas/sft/ws/root-project/build/Debug/etc//cling/lib/clang/18/include/__clang_cuda_device_functions.h:51:18: error: static declaration of '__cosf' follows non-static declarat
ion
__DEVICE__ float __cosf(float __a) { return __nv_fast_cosf(__a); }
                 ^
cling: /usr/include/x86_64-linux-gnu/bits/mathcalls.h:62:1: note: previous declaration is here
__MATHCALL_VEC (cos,, (_Mdouble_ __x));

TODOs:

• Solve remaining issues described above
• Add test script to roottest
• Solve quick fixes in the code in a more fundamental way
• Write more test cases

[github-actions]

Test Results

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0 suites  0 💤
0 files    0 ❌

Results for commit a60c2de.