21.5-b28 strange behaviour: buffer modification flag set, even though I can't remember having changed anything, patch for configure on aix

[Stephen J. Turnbull]

Thomas Mittelstaedt writes:

Thanks for following up!  BTW, is the buffer modification problem gone?

 > Just built xemacs without -pthread (or -mthreads) and it runs. The gcc 
 > 4.2.2 man page says about -mthreads that it's needed
 > for multi-threaded exception handling on mingw.

That looks like an irrelevancy to me, since mingw is a GCC runtime
environment for Microsoft Windows.  I suspect that some other AIX
compiler (possibly obsolete) does need -mthreads, which has semantics
specific to that compiler.

Don't feel you *need* to dig, but if you do find any references or
conversation at an AIX user group or whatever, we'd greatly appreciate
an update!

 > We use -pthread to link with the correct, multi-threaded version of
 > the libstdc++ library, which on aix 5.2 are in separate directories:

pthreads should be irrelevant to XEmacs, even with --xemacs-compiler=c++.

 > tmstaedt at buildaix3$ find /opt/gcc-4.2.2/lib -name libstdc++*
 > /opt/gcc-4.2.2/lib/gcc/powerpc-ibm-aix5.2.0.0/4.2.2/pthread/ppc64/libstdc++.a
 > /opt/gcc-4.2.2/lib/gcc/powerpc-ibm-aix5.2.0.0/4.2.2/pthread/ppc64/libstdc++.la
 > /opt/gcc-4.2.2/lib/gcc/powerpc-ibm-aix5.2.0.0/4.2.2/pthread/libstdc++.a
 > /opt/gcc-4.2.2/lib/gcc/powerpc-ibm-aix5.2.0.0/4.2.2/pthread/libstdc++.la
 > /opt/gcc-4.2.2/lib/gcc/powerpc-ibm-aix5.2.0.0/4.2.2/ppc64/libstdc++.a
 > tmstaedt at buildaix3$ gcc -v
 > Using built-in specs.
 > Target: powerpc-ibm-aix5.2.0.0
 > Configured with: ../gcc-4.2.2/configure 
 > --enable-version-specific-runtime-libs --enable-static --enable-shared 
 > --enable-threads --with-as=/usr/bin/as --without-gnu-ld 
 > --with-ld=/usr/bin/ld --prefix=/opt/gcc-4.2.2 --disable-nls --with-pic 
 > --disable-symvers --enable-symvers=no --enable-languages=c,c++,objc
 > Thread model: aix
 > gcc version 4.2.2

Thank you!