GH-131296: fix clang-cl warning in tracemalloc.c #131374
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| @@ -53,7 +53,8 @@ typedef struct tracemalloc_traceback traceback_t; | |||
| /* The maximum number of frames is either: | |||
| - The maximum number of frames we can store in `traceback_t.nframe` | |||
| - The maximum memory size_t we can allocate */ | |||
| static const unsigned long MAX_NFRAME = Py_MIN(UINT16_MAX, ((SIZE_MAX - sizeof(traceback_t)) / sizeof(frame_t) + 1)); | |||
| static const unsigned long MAX_NFRAME = (unsigned long)Py_MIN( | |||
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Fix warning implicit conversion from 'unsigned long long' to 'const unsigned long' changes value from 1537228672809129300 to 1431655764 [-Wconstant-conversion]
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I'm not sure that this change is needed. It should return UINT16_MAX which fits into unsigned long. IMO this code is too complicated, it's not worth it. I wrote a simpler but different fix: #131514 (note: I'm the author of this code ;-)).
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Oh, much simpler. Didn't dare to do it, since there might be some weird targets where unsigned long is only 16 bit, but those are most probably not existing these days anymore :)
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Right, I merged my PR. Thanks anyway!
This one is really interesting. Only clang-cl issues it - not clang or GCC on Linux: https://godbolt.org/z/57oaaTcbT
Interestingly enough, clang-cl even emits this warning without any options given (i.e. the default warning level), on the not taken branch in
Py_MIN(x, y) (((x) > (y)) ? (y) : (x)).I had to use C++ on godbolt, because clang-cl is not available as C compiler, but I get the same error for that file when compiling the C file
tracemalloc.clocally.The fix is easy, although seeming very unneeded :(