Fix some undefined behavior from casting in dt_arith.c#6456
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jhendersonHDF wants to merge 1 commit into
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Fix some undefined behavior from casting in dt_arith.c#6456jhendersonHDF wants to merge 1 commit into
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Review ChecklistThis PR touches the following areas. Each needs at least one
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brtnfld
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brtnfld
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| float f; | ||
| memcpy(&f, src_buf + idx * sizeof(float), sizeof(float)); | ||
| aligned = (long long)f; | ||
| if (f > (float)(LLONG_MAX)) |
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There are possibly some comparison issues here with certain types due to rounding in specific compilers, but this is currently just matching the logic in the library so the testing passes
brtnfld
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| aligned = (unsigned char)f16; | ||
| if (f16 > (H5__Float16)(UCHAR_MAX)) | ||
| aligned = UCHAR_MAX; | ||
| else if (f16 < (H5__Float16)0) |
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Don't you also need this for to_ushort/to_uint/to_ulong/to_ullong
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In this case no, because the conversion logic in the library doesn't perform any checks since we're guaranteed that an f16 will fit into ushort and larger
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Fixes some more undefined behavior in dt_arith.c due to casting floating-point type values into integer types that can't represent the values. Emulates what the library is doing internally in conversion routines. There is still some remaining undefined behavior in the library itself (exposed by dt_arith.c) from not checking for NaN values before casting them to integer types.