Re: What is wrong with Bugzilla? [Was: Re: GCC and Floating-Point]

[Haren Visavadia <themis_hv at yahoo dot co dot uk>]

--- Robert Dewar wrote:
> And so? Why would you expect this particular example
> to give an assertion error. I would not expect an
> assert error here. In unoptimized mode, you
> certainly
> do not expect it, and in optimized mode, I would
> expect the register tracker to know that a and x are
> in the same register at the point of assertion (and
> perhaps even eliminate the comparison entirely).
> 

The previous posted case only adds few new lines of
insignificant line of code from:


test-case.c:
#include <assert,h>
volatile float x = 3;
int main()
{
float a = 1 / x;
x = a;
assert(a == x);
}


to

test.c:
#include <assert.h>
#include <stdio.h>

volatile float x = 3;

int main()
{
	float a = 1 / x;
	x = a;
	assert(a == x);
	printf("a has value of %g \n",a);
	printf("x has value of %g  \n",x);
	assert((int)a == 0);
	assert((int)x == 0);
	return 0;
}


I would expect the seem behaviour for both cases.

test-case.c cause an assertion failure with
{-O1,-O2,-O3} but test.c does not all.

The first few lines of both case are pretty simalar.














	
	
		
___________________________________________________________ 
Yahoo! Messenger - NEW crystal clear PC to PC calling worldwide with voicemail http://uk.messenger.yahoo.com