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author | Brett Cannon <bcannon@gmail.com> | 2011-01-19 23:08:44 (GMT) |
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committer | Brett Cannon <bcannon@gmail.com> | 2011-01-19 23:08:44 (GMT) |
commit | 41c4da704da893db6c2cc2ccac35ecb38d6e773d (patch) | |
tree | d6a7a751a242fccd2020ca6f4fe14d3a5f43c1f5 /Misc/README.AIX | |
parent | ecdd63f56c7d2e890a5182f6d47aa29e4ec95022 (diff) | |
download | cpython-41c4da704da893db6c2cc2ccac35ecb38d6e773d.zip cpython-41c4da704da893db6c2cc2ccac35ecb38d6e773d.tar.gz cpython-41c4da704da893db6c2cc2ccac35ecb38d6e773d.tar.bz2 |
Rename AIX-NOTES to something that follows the convention in Misc.
Diffstat (limited to 'Misc/README.AIX')
-rw-r--r-- | Misc/README.AIX | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/Misc/README.AIX b/Misc/README.AIX new file mode 100644 index 0000000..d928f53 --- /dev/null +++ b/Misc/README.AIX @@ -0,0 +1,155 @@ +Subject: AIX - Misc/AIX-NOTES +From: Vladimir Marangozov <Vladimir.Marangozov@imag.fr> +To: guido@CNRI.Reston.Va.US (Guido van Rossum) +Date: Wed, 6 Aug 1997 11:41:00 +0200 (EET) + +============================================================================== + 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 separator, + 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 +------------------------------------------------------------------------------ + +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 "*shared*" line in Modules/Setup before the +build. + +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 "export" file (named python.exp) for the modules and the +libraries that belong to the Python core is created by the "makexp_aix" +script before performing the link of the python binary. It lists all global +symbols (exported during the link) of the modules and the libraries that +make up the python executable. + +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. + +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. + +NOTE: If the extension module is written in C++ and contains templates, + an alternative to "ld_so_aix" is the /usr/lpp/xlC/bin/makeC++SharedLib + script. Chris Myers (myers@TC.Cornell.EDU) reports that ld_so_aix + works well for some C++ (including the C++ that is generated + automatically by the Python SWIG package [SWIG can be found at + http://www.cs.utah.edu/~beazley/SWIG/swig.html]). However, it is not + known whether makeC++SharedLib can be used as a complete substitute + for ld_so_aix. + +According to Gary Hook from IBM, the format of the export file changed +in AIX 4.2. For AIX 4.2 and later, a period "." is required on the +first line after "#!". If python crashes while importing a shared +library, you can try modifying the LINKCC variable in the Makefile. +It probably looks like this: + + LINKCC= $(srcdir)/Modules/makexp_aix Modules/python.exp \"\" $(LIBRARY); $(PURIFY) $(CXX) + +You should modify the \"\" to be a period: + + LINKCC= $(srcdir)/Modules/makexp_aix Modules/python.exp . $(LIBRARY); $(PURIFY) $(CXX) + +Using a period fixed the problem in the snake farm. YMMV. +This fix has been incorporated into Python 2.3. + +============================================================================== |