The return value is now -NaN. This fixes a bug in the mingw-w64 code that was imported into Cygwin. The fix is consistent with Posix and Linux. It is also consistent with the current mingw-w64 code, with one exception: The mingw-w64 code sets errno to EDOM if the input is -NaN, but this appears to differ from Posix and Linux.
Addresses: https://cygwin.com/pipermail/cygwin/2020-October/246606.html --- winsup/cygwin/math/sqrt.def.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/winsup/cygwin/math/sqrt.def.h b/winsup/cygwin/math/sqrt.def.h index cf8b5cbe6..3d1a00908 100644 --- a/winsup/cygwin/math/sqrt.def.h +++ b/winsup/cygwin/math/sqrt.def.h @@ -73,8 +73,11 @@ __FLT_ABI (sqrt) (__FLT_TYPE x) if (x_class == FP_ZERO) return __FLT_CST (-0.0); + if (x_class == FP_NAN) + return x; + errno = EDOM; - return x; + return -__FLT_NAN; } else if (x_class == FP_ZERO) return __FLT_CST (0.0); -- 2.28.0
