Subject: Re: bug#17598: Emacs pretest 24.3.91 - AIX - SIGSEV when customize

From: Dmitry Antipov <[email-masked]>
Date: Tue, 03 Jun 2014 18:01:47 +0400

On 06/03/2014 09:28 AM, Gilles PION wrote:

> Could you suggest sensible configure options to rebuilt
> a definitive version and to confirm everything is OK now?

Hm...here is what I can suggest for trunk on AIX.

1. Choose the compiler.
    IIUC gcc can't create 64-bit binaries on AIX, but xlc can (-q64).
    Note build with gcc is far more well tested, and I have no ideas
    whether unexec will work for 64-bit XCOFF binary.

2. Choose CFLAGS.
    If you don't want to debug, just use '-O2' for both gcc and xlc.
    If you want to debug, add '-g3' for gcc and up to '-g9' for xlc
    (for the latter, please report your results!).
    If you want to fight for 1% with the very unexpected results, try:
      for gcc:
         - determine CPU type with 'prtconf | grep -i "Processor Type"'
           ==> Processor Type: PowerPC_POWERX (where X is Power core
           generation) and use CFLAGS='-O3 -mcpu=powerX -mtune=powerX'
      for xlc, try '-O5'.

3. Choose configuration options.

    For some weird reasons, you can't link without -lXpm (probably some
    other library from vendor's X requires it). So use:
      --without-all --with-xpm
    to get the bare minimum executable with X support. This is pretty
    enough to do basic programming tasks (i.e. editing source code).

    If you want more features, look through 'configure --help' output,
    choose the features you want, install required external libraries,
    and then try '--without-all --with-FEATURE'. Note that just
    'configure' (with no options) means the most feature-rich configuration
    which may be compiled with installed headers and libraries.

Dmitry