On Mon, 7 Oct 2024 15:11:52 +0200 Christian Franke wrote: > $ gcc -o sigtest -O2 sigtest.c > > $ ./sigtest > out.txt > (press ^C 42x :-) > > $ sort out.txt | uniq -c > 3 x = 0x1.23456789p+0, y = -nan, d = -nan > 6 x = 0x1.23456789p+0, y = 0x1.23456789p+0, d = -nan > 33 x = 0x1.23456789p+0, y = 0x1.23456789p+0, d = 0x0p+0 > > The problem also occurs if compiled without -O2, but less often. No > problem occurs if compiled with -DWORKS which suggests that only 'long > double' is affected.
Thanks for the report. I looked into this problem and might find the cause. It seems due to a bug of scripts/gendef. It generates signal handler caller (sigfe.s) which stores/restores the registers. In sigdelayed, control word is stored/restored by fnstcw/fldcw instruction, however, fninit instruction destroys some status registers in FPU (x87). I think we shold use fnstenv/fldenv rather than fnstcw/fldcw and fninit. However, I'm not familiar with x87 instructions, so I may overlook something. Could anyone expert of x87 instructions and sigfe stuff give some comments? -- Takashi Yano <takashi.y...@nifty.ne.jp> -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
