[Flac-dev] Segfaults on K7

[Matt Zimmerman]

On Tue, Oct 16, 2001 at 06:34:38PM -0700, Josh Coalson wrote:

> --- Asheesh Laroia <PaulProteus at technologist.com> wrote:
> > This K7 doesn't segfault on flac as provided by the .debs.  (See
> > /proc/cpuinfo at end of message.)  If there are any particular
> > circumstances you want me to test, feel free to ask.
> 
> My hunch is that it's related either to the SSE or 3DNOW
> asm routines.  I thought that the 3DNOW implementation
> was turned off by default in 1.0 since I couldn't test
> it myself.  SSE needs OS support to work and the patch
> to determine support at runtime came after 1.0.  In 1.0,
> I think it is turned off unless you pass a flag to
> configure.

The segfault occurs immediately at startup, even when no operations are
specified (i.e., only the help would have been displayed).  Assuming the
detection code is always run at startup (I haven't checked), it may be
that code itself which is causing the crash.

The backtrace is useless:

Program received signal SIGSEGV, Segmentation fault.
0x4000960c in ?? ()
(gdb) bt
#0  0x4000960c in ?? ()
#1  0x40003728 in ?? ()
#2  0x4000d179 in ?? ()
#3  0x4000250e in ?? ()
#4  0x4000247f in ?? ()

If I compile with --disable-shared to statically link in libFLAC, the
problem goes away.  If I set a breakpoint for entry to 'main', the
problem still happens, before the breakpoint(!).

-- 
 - mdz