STM CircleOS forum / floating point bugg?

sima · 2009-03-14 14:55:16

What's happening here?

float x, y, z;

x = 843314856.53262618491243641555602;
y = 1.0/536870912.0;

z = x*y;

I see the following values in the debugger window (using SIM-ARM):

x = 8.43315e+08
y = 1.86265e-09
z = 6.70968e-39 <----- Error, should eveluete to 1.57080068475000

Francis · 2009-03-15 11:27:54

we'll check. At a first sight, it would be a bug in the instruction- set simulator. Because the hw debug is quite powewrfull with the Cortex-M3, we generally recommend not using the softwware simulator.

sima · 2009-03-15 19:25:30

I tried some floating point functions at home where I don't have any hardware (this was when I saw the bug). I'll try the code in hardware tomorrow.

sima · 2009-03-16 07:43:11

It worked when I debugged the code in hardware today.

# 1 2009-03-14 14:55:16 floating point bugg?

floating point bugg?

# 2 2009-03-15 11:27:54 floating point bugg?

Re: floating point bugg?

# 3 2009-03-15 19:25:30 floating point bugg?

Re: floating point bugg?

# 4 2009-03-16 07:43:11 floating point bugg?

Re: floating point bugg?

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