atomics detection is broken #141
Comments
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Once |
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The code below from CMakeLists.txt seems to be broken using the latest OSes, compilers, ... Ideally we would like to replace the code above and use a proper CMake module for libatomic. This did not exist a few years ago, but according to ChatGPT we could now potentially use: # If atomic 64-bit code fails to compile then we
# need to add libatomic to the linker flags.
if(NOT atomic64)
find_package(LibAtomic REQUIRED)
set(LIBATOMIC ${LibAtomic_LIBRARIES})
message(STATUS "Found libatomic: ${LIBATOMIC}")
endif()instead of: if(NOT atomic64)
find_library(ATOMIC NAMES atomic libatomic.so.1)
if(ATOMIC)
set(LIBATOMIC ${ATOMIC})
message(STATUS "Found libatomic: ${LIBATOMIC}")
else()
check_cxx_source_compiles("
#include <atomic>
#include <stdint.h>
int main() {
std::atomic<int32_t> x;
x = 1;
x--;
return (int) x;
}"
atomic32)
if(atomic32)
message(FATAL_ERROR "Failed to find libatomic!")
endif()
endif()
endif()I have not tested this yet, if it works there is a high risk that it will only work on newer OSes. |
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I am pretty sure extension should not be added to a library name in the check. Also on Mac is will be |
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Another option that would likely fix the problem and work well on old OSes is: if(NOT atomic64)
find_library(ATOMIC NAMES atomic libatomic.so.1)
if(ATOMIC)
set(LIBATOMIC ${ATOMIC})
message(STATUS "Found libatomic: ${LIBATOMIC}")
else()
# Try -latomic as a fallback if our code fails to detect libatomic
set(LIBATOMIC atomic)
message(STATUS "Found libatomic: ${LIBATOMIC}")
endif()
endif() |
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@kimwalisch Something like this should work: pghysels/STRUMPACK@be6d1f6 See also: https://github.com/grpc/grpc/pull/21341/files P. S. I should open an issue with CMake upstream, this has to be really implemented with CMake to begin with. |
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@barracuda156 Can you please let me know where libatomic is located on your PC and how it is named? I have found another code snippet online that I think is superior to the solutions I have seen so far: https://github.com/agroal/pgagroal/blob/master/cmake/FindLibatomic.cmake#L6. It is similar to the code used in primesieve but it includes hints to a list of paths where libatomic cloud potentially be located if the compiler/linker cannot find it in the default path. |
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@barracuda156 Could you please try if the following fix works on your PC? Add instead of: In the |
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I was able to partially reproduce your issue on macOS 14.2 with homebrew GCC 13.2. I tried all of the potential solutions discussed in this thread, in the end the only solution that worked was adding -latomic to the linker options. So I have added this method as a fallback (https://github.com/kimwalisch/primesieve/blob/master/cmake/libatomic.cmake#L39) in case our other methods fail to find libatomic. Could you please try if the latest code from the master branch works fine on your PC? |
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@kimwalisch Sorry, it was a busy day, I am off the machine now. I can verify tomorrow, but passing |
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Closing, I assume I have fixed this. |
This is GCC, so obviously
libatomicis there. The check is not looking for it at all however:Of course it will not work without passing
-latomicflag.The text was updated successfully, but these errors were encountered: