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mips/mipsel linux user float division problem
Hi,
I tested the following with the qemu git HEAD as of 2013-09-30 on Debian stable and testing. My host runs amd64 but I also tried this out inside a i386 chroot with the same result. The problem occurs for mips and mipsel. Given the following program:
#include <stdio.h>
int main(int argc, char **argv)
{
int a = 1;
double d = a/2.0;
printf("%f\n", d);
return 0;
}
Instead of printing 0.5, it will print 2.0 if executed in qemu user mode.
$ mipsel-linux-gnu-gcc mipstest.c
$ ~/qemu/mipsel-linux-user/qemu-mipsel ./a.out
2.0
Expecting this to be a problem with my cross compiler (gcc-4.4 from emdebian) I ran a fully emulated debian squeeze environment inside qemu. There, I compiled the same program natively with gcc and as expected got 0.5 as the output. I also copied the cross compiled binary inside the emulated environment and also got 0.5 when I ran it. So the same mips/mipsel binary produces different output depending on whether it is run in a fully emulated environment or qemu user mode.
Can anybody else reproduce this problem?
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