Re: stack alignment bug in gcc 2.95.2

[David Ronis <ronis at ronispc dot chem dot mcgill dot ca>]

Jeffrey Law wrote:

     >Alignment can only be preserved if the OS & dld arrange to
     provide main
     >with an aligned stack.
     >
     >If it's mis-aligned  when main is called, there's little
     we're going
     >to be able to do about the problem.

Steven G. Johnson answered:


     I've modified my test program slightly to check whether the
     stack is
     aligned in main() (see below).  It is.  Then, in the
     subroutine "blah", it
     is misaligned.  So, it really seems like a bug in gcc's stack
     alignment.
     Can you suggest anything else to try?


Could someone post a few words on just where this misalignment is
creeping in.  It clearly shouldn't be gcc's
startup files' job to fix a sloppy loader  or worse OS (but it might be
the quickest way to fix the problem).

I'm running linux-2.2.13; should I be talking to the linux developers?
The ld-so folks?   The glibc2 folks?

It may be my imagination, but lots of things seem to be running slower
since upgrading from libc5 to glibc-2.1.2, but I don't
want to draw any conclusions...


David