The bug is in the same area as https://bugs.launchpad.net/qemu/+bug/1821444 but in another branch of 'uint64_t helper_todouble(uint32_t arg=0x1)'.
-- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1821515 Title: qemu-ppc (user) incorrectly converts float(nan)->double(non-nan) Status in QEMU: New Bug description: Noticed on qemu-3.1.0 on GHC test suite where float32 comparisons didn't work on NaNs. Here is the minimal reproducer: ```c // cat a.c #include <stdio.h> #include <math.h> #include <stdint.h> int main() { volatile float f1 = NAN; volatile float f2 = NAN; printf ("f1 (%e, %#x) >= f2 (%e, %#x): %s\n", f1, *(volatile uint32_t*)&f1, f2, *(volatile uint32_t*)&f2, (f1 >= f2) ? "True" : "False"); volatile double d = f1; printf ("d (%e, %#llx)\n", d, *(volatile uint64_t*)&d); } ``` ``` # incorrect execution: $ powerpc-unknown-linux-gnu-gcc -O2 a.c -o a -static && qemu-ppc ./a f1 (5.104236e+38, 0x7fc00000) >= f2 (5.104236e+38, 0x7fc00000): True d (5.104236e+38, 0x47f8000000000000) # correct execution $ scp a timberdoodle.ppc64.dev.gentoo.org:~/; ssh timberdoodle.ppc64.dev.gentoo.org ./a f1 (nan, 0x7fc00000) >= f2 (nan, 0x7fc00000): False d (nan, 0x7ff8000000000000) ``` Note: qemu-ppc handled float32 extension as it was not a NaN (exp=111..1111) but a normalized number. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1821515/+subscriptions
