[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [avr-gcc-list] Re: WinAVR 20050214 (gcc 3.4.3) and optimizer bug.

From: E. Weddington
Subject: Re: [avr-gcc-list] Re: WinAVR 20050214 (gcc 3.4.3) and optimizer bug.
Date: Sun, 08 May 2005 21:30:26 -0600
User-agent: Mozilla Thunderbird 1.0 (Windows/20041206)

Vesa Jääskeläinen wrote:

Joerg Wunsch wrote:

As Vesa Jääskeläinen wrote:

I have been debugging why Ethernut brakes in certain situations with
gcc. And found an optimizer bug.

In this clause:
        if (ppv && (*ppv != 0)) {

We are missing code for (ppv != 0), but code for *ppv != 0 is found. And
 if I pass NULL to this function it makes compare to incorrect memory

Regardless of whether there is a compiler bug, the above is incorrect C. You are NEVER supposed to rely on the fact that a NULL pointer is equal to zero, because, technically, it can be defined as something else. You should always directly compare a pointer to NULL as such:

if(ppv != NULL && (*ppv != 0))


reply via email to

[Prev in Thread] Current Thread [Next in Thread]