From 2e48c8dd317819645581058f662f1e8cb6e35d6e Mon Sep 17 00:00:00 2001 From: Vasyl Gello Date: Mon, 20 Jul 2020 20:18:02 +0300 Subject: [PATCH] tests: Check for both quiet and signaling NaN on mipsel/hppa (#6029) MIPSEL, MIPS64EL and HP-PA architectures have quiet and signaling NaNs swapped. The test assumes correct values for i386 / amd64 but obviously fails on these architectures. It is documented in many places, like https://software.llnl.gov/yorick-doc/stdlib/ieee.html : Warning-- apparently there is no universal standard for what constitutes signalling versus quiet NaN on MIPS and HPPA architectures, qNaN and sNaN are reversed https://gcc.gnu.org/onlinedocs/gcc/MIPS-Options.html : -mnan=2008 -mnan=legacy These options control the encoding of the special not-a-number (NaN) IEEE 754 floating-point data. The -mnan=legacy option selects the legacy encoding. In this case quiet NaNs (qNaNs) are denoted by the first bit of their trailing significand field being 0, whereas signaling NaNs (sNaNs) are denoted by the first bit of their trailing significand field being 1. The -mnan=2008 option selects the IEEE 754-2008 encoding. In this case qNaNs are denoted by the first bit of their trailing significand field being 1, whereas sNaNs are denoted by the first bit of their trailing significand field being 0. The default is -mnan=legacy unless GCC has been configured with --with-nan=2008. The behavior mentioned above causes FTBFS in Debian starting with 1.12.0: https://buildd.debian.org/status/fetch.php?pkg=flatbuffers&arch=mips64el&ver=1.12.1%7Egit20200711.33e2d80%2Bdfsg1-0.1&stamp=1594830681&raw=0 https://buildd.debian.org/status/fetch.php?pkg=flatbuffers&arch=mipsel&ver=1.12.1%7Egit20200711.33e2d80%2Bdfsg1-0.1&stamp=1594832647&raw=0 https://buildd.debian.org/status/fetch.php?pkg=flatbuffers&arch=hppa&ver=1.12.1%7Egit20200711.33e2d80%2Bdfsg1-0.1&stamp=1594830726&raw=0 For HP-PA (PA-RISC) there is no way to override the reversal, and for MIPSEL/MIPS64EL there is no macro defining the '-mnan' choice, so both variants were added with OR boolean operator. Signed-off-by: Vasyl Gello --- tests/test.cpp | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/tests/test.cpp b/tests/test.cpp index de86f02..b4a358c 100644 --- a/tests/test.cpp +++ b/tests/test.cpp @@ -678,12 +678,23 @@ template bool is_quiet_nan_impl(T v) { std::memcpy(&b, &v, sizeof(T)); return ((b & qnan_base) == qnan_base); } +#if defined(__mips__) || defined(__hppa__) +static bool is_quiet_nan(float v) { + return is_quiet_nan_impl(v) || + is_quiet_nan_impl(v); +} +static bool is_quiet_nan(double v) { + return is_quiet_nan_impl(v) || + is_quiet_nan_impl(v); +} +#else static bool is_quiet_nan(float v) { return is_quiet_nan_impl(v); } static bool is_quiet_nan(double v) { return is_quiet_nan_impl(v); } +#endif void TestMonsterExtraFloats() { TEST_EQ(is_quiet_nan(1.0), false); -- 2.7.4