Re: [3.3 branch] IA64 bootstrap failure

["H. J. Lu" <hjl at lucon dot org>]

On Tue, Jul 08, 2003 at 03:53:38PM -0700, Jim Wilson wrote:
> Andreas Schwab wrote:
> >Running the same (stage2) compiler command on the command line produces
> >output that is the same as the output from the stage1 compiler.  So it
> >indeed looks like it's dependent on the environment size.
> 
> I've debugged problems like this before.  You vary the environment size 
> until you can reproduce the problem, and then you debug two compilers in 
> parallel with different environment sizes until you figure out why they 
> emit different code.  Probably an uninitialized variable or a 
> stray/out-of-bounds memory reference somewhere.  Another possibly is 
> that addresses are being used (e.g. in a hash table) and there is a 
> latent bug in the code.
> 

A few things I noticed:

1. It doesn't happen with -da.
2. It doesn't happen with debug is off.
3. It doesn't happen with preprocessed input.
3. It is very sensitive to input. Removing a few lines or adding
"#if 0/#endif" will make it to go away.

I have been working on Intel IA64 intrinsics. Since the compiler is not
miscompiled, I will go back to take another look after I finish my
intrinsics work.

H.J.