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Showing content with the highest reputation on 01/14/2017 in all areas

  1. 1 point
    The regression suite, files systemc-regressions-2.3.1a/tests/systemc/datatypes/fx/constructors/array.cpp systemc-regressions-2.3.1a/tests/systemc/datatypes/fx/fast_constructors/array.cpp systemc-regressions-2.3.1a/tests/systemc/datatypes/misc/test02/test02.cpp invoke undefined behaviour by converting out-of-range doubles to unsigned integers directly. This is undefined in the C++ standard See http://stackoverflow.com/a/4752947/1763356 for further information. This happens multiple most prominently in the code sc_fxval *b = new sc_fxval[4]; b[0] = (ushort)-1; for (i = 1; i < 4; ++i) b[i] = (ushort)(b[i-1] * i * -1); where negative doubles are converted to unsigned shorts, because sc_fxval only has conversions to double. It is unclear whether the test is correct and sc_fxval wrong, or vice-versa. If the later, one can avoid undefined behaviour by indirecting through a sufficiently large signed type. sc_fxval *b = new sc_fxval[4]; b[0] = (ushort)-1; for (i = 1; i < 4; ++i) b[i] = (ushort)(int64)(b[i-1] * i * -1); I was caught by this issue when testing a build of SystemC for AArch64, as part of a port I am making. As an aside, how (and where) should I attempt to upstream my port when it is ready?