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+Subject: HERE IS AIX-NOTES
+From: Manus Hand <Manus.Hand@evolving.com>
+To: Guido van Rossum <guido@CNRI.Reston.VA.US>
+Cc: Vladimir.Marangozov@imag.fr
+Date: Thu, 8 Aug 1996 16:11:10 -0600 (MDT)
+
+==============================================================================
+                              COMPILER INFORMATION
+------------------------------------------------------------------------------
+
+(1) A problem has been reported with "make test" failing because of "weird
+    indentation."  Searching the comp.lang.python newsgroup reveals several
+    threads on this subject, and it seems to be a compiler bug in an old
+    version of the AIX CC compiler.  However, the compiler/OS combination
+    which has this problem is not identified.  In preparation for the 1.4
+    release, Vladimir Marangozov (Vladimir.Marangozov@imag.fr) and Manus Hand
+    (mhand@csn.net) reported no such troubles for the following compilers and
+    operating system versions:
+       AIX C compiler version 3.1.2 on AIX 4.1.3 and AIX 4.1.4
+       AIX C compiler version 1.3.0 on AIX 3.2.5
+    If you have this problem, please report the compiler/OS version.
+
+(2) Stefan Esser (se@MI.Uni-Koeln.DE), in work done to compile Python
+    1.0.0 on AIX 3.2.4, reports that AIX compilers don't like the LANG
+    environment varaiable set to European locales.  This makes the compiler
+    generate floating point constants using "," as the decimal seperator,
+    which the assembler doesn't understand (or perhaps it is the other way
+    around, with the assembler expecting, but not getting "," in float
+    numbers).  "LANG=C; export LANG" solves the problem, as does
+    "LANG=C $(MAKE) ..." in the master Makefile.
+
+(3) The cc (or xlc) compiler considers "Python/ceval.c" too complex to
+    optimize, except when invoked with "-qmaxmem=4000"
+
+(4) Some problems (due to _AIX not being #defined) when python 1.0.0 was
+    compiled using 'gcc -ansi' were reported by Stefan Esser, but were not
+    investigated.
+
+(5) The cc compiler has internal variables named "__abs" and "__div".  These
+    names are reserved and may not be used as program variables in compiled
+    source.  (As an anecdote in support of this, the implementation of
+    Python/operator.c had this problem in the 1.4 beta releases, and the
+    solution was to re#define some core-source variables having these names,
+    to give these python variables different names if the build is being done
+    on AIX.)
+
+(6) As mentioned in the README, builds done immediately after previous builds
+    (without "make clean" or "make clobber") sometimes fail for mysterious
+    reasons.  There are some unpredictable results when the configuration
+    is changed (that is, if you "configure" with different parameters) or if
+    intermediate changes are made to some files.  Performing "make clean" or
+    "make clobber" resolves the problems.
+
+==============================================================================
+                                THREAD SUPPORT
+------------------------------------------------------------------------------
+
+AIX uses pthreads.  However, as of AIX version 4, there are two (incompatible)
+types of pthreads on AIX:
+        a)  AIX DCE pthreads (on AIX 3.2.5)
+        b)  AIX 4 pthreads (on AIX 4.1 and up)
+Support has been added to Python to handle the distinction.
+
+The cc and gcc compilers do not initialize pthreads properly. The only
+compilers that can initialize pthreads properly are IBM *_r* compilers,
+which use the crt0_r.o module, and which invoke ld with the reentrant
+version of libc (libc_r).
+
+In order to enable thread support, follow these steps:
+   1.  Uncomment the thread module in Modules/Setup
+   2.  configure --without-gcc --with-thread ...
+   3.  make CC="cc_r" OPT="-O -qmaxmem=4000"
+
+For example, to make with both threads and readline, use:
+  ./configure --without-gcc --with-thread --with-readline=/usr/local/lib
+  make CC=cc_r OPT="-O2 -qmaxmem=4000"
+
+If the "make" which is used ignores the "CC=cc_r" directive, one could alias
+the cc command to cc_r (for example, in C-shell, perform an "alias cc cc_r").
+
+Vladimir Marangozov (Vladimir.Marangozov@imag.fr) provided this information,
+and he reports that a cc_r build initializes threads properly and that all
+demos on threads run okay with cc_r.
+
+==============================================================================
+                            SHARED LIBRARY SUPPORT
+------------------------------------------------------------------------------
+
+AIX shared library support was added to Python in the 1.4 release by Manus
+Hand (mhand@csn.net) and Vladimir Marangozov (Vladimir.Marangozov@imag.fr).
+
+Python modules may now be built as shared libraries on AIX using the normal 
+process of uncommenting the "*noconfig*" line in Modules/Setup.in before the
+build.  There is one additional step required, and that is to also uncomment
+the line in Modules/Setup.in which reads
+    LINKCC= makexp_aix python.exp "" $(MYLIBS) $(ADDOBJS) ; $(CC)
+
+AIX shared libraries require that an "export" and "import" file be provided
+at compile time to list all extern symbols which may be shared between
+modules.  The effect of uncommenting the LINKCC line in Modules/Setup.in is
+to create the "export" file for the modules and the libraries that belong to
+the Python core.  This is done by the "makexp_aix" script, which creates a
+file named python.exp before performing the link of the python binary.
+
+When shared library modules (.so files) are made, a second shell script
+is invoked.  This script is named "ld_so_aix" and is also provided with
+the distribution in the Modules subdirectory.  This script acts as an "ld"
+wrapper which hides the explicit management of "export" and "import" files;
+it adds the appropriate arguments (in the appropriate order) to the link
+command that creates the shared module.  Among other things, it specifies
+that the "python.exp" file is an "import" file for the shared module.
+
+A default python.exp file is provided with the distribution.  It will be
+overwritten (by the action of the makexp_aix script) if you build with shared
+libraries.  The python.exp file which comes with the distribution contains
+all extern symbols of a completely statically build python executable.
+Any python.exp file which is created from a build of python with some of the
+modules linked as shared modules will obviously not list symbols from the now
+dynamic modules.  The distributed python.exp is provided so that, with
+assistance from the ld_so_aix and makexp_aix scripts, shared extension
+modules may be added to an otherwise completely static python build.
+
+At the time of this writing, neither the python.exp file nor the makexp_aix
+or ld_so_aix scripts are installed by the make procedure, so you should
+remember to keep these and/or copy them to a different location for
+safekeeping if you wish to use them to add shared extension modules to
+python.  However, if the make process has been updated since this writing,
+these files MAY have been installed for you during the make by the
+LIBAINSTALL rule, in which case the need to make safe copies is obviated.
+
+If you wish to add a shared extension module to the language, you would follow
+the steps given in the example below (the example adds the shared extension
+module "spam" to python):
+    1.  Make sure that "ld_so_aix" and "makexp_aix" are in your path.
+    2.  The "python.exp" file should be in the current directory.
+    3.  Issue the following commands or include them in your Makefile:
+            cc -c spammodule.c
+            ld_so_aix cc spammodule.o -o spammodule.so
+
+For more detailed information on the shared library support, examine the
+contents of the "ld_so_aix" and "makexp_aix" scripts or refer to the AIX
+documentation.
+
+==============================================================================