Construct a correct value of PYTHONHOME from the interpreter

running SCons, make it into a sticky option that can be
overridden at build time, and set it up before the interpreter
is started.  Also, fix the code that turns sticky options into
config/*.hh so that it works with types other than bool.

--HG--
extra : convert_revision : 602398b35d4da4e813f78865678ed348fdea7270

SConstruct

@@ -347,7 +347,10 @@ sticky_opts.AddOptions(
     ('CC', 'C compiler', os.environ.get('CC', env['CC'])),
     ('CXX', 'C++ compiler', os.environ.get('CXX', env['CXX'])),
     BoolOption('BATCH', 'Use batch pool for build and tests', False),
-    ('BATCH_CMD', 'Batch pool submission command name', 'qdo')
+    ('BATCH_CMD', 'Batch pool submission command name', 'qdo'),
+    ('PYTHONHOME',
+     'Override the default PYTHONHOME for this system (use with caution)',
+     '%s:%s' % (sys.prefix, sys.exec_prefix))
     )
 
 # Non-sticky options only apply to the current build.
@@ -359,7 +362,7 @@ nonsticky_opts.AddOptions(
 # These options get exported to #defines in config/*.hh (see src/SConscript).
 env.ExportOptions = ['FULL_SYSTEM', 'ALPHA_TLASER', 'USE_FENV', \
                      'USE_MYSQL', 'NO_FAST_ALLOC', 'SS_COMPATIBLE_FP', \
-                     'USE_CHECKER']
+                     'USE_CHECKER', 'PYTHONHOME']
 
 # Define a handy 'no-op' action
 def no_action(target, source, env):
@@ -399,8 +402,13 @@ def config_emitter(target, source, env):
     option = str(target[0])
     # True target is config header file
     target = os.path.join('config', option.lower() + '.hh')
-    # Force value to 0/1 even if it's a Python bool
-    val = int(eval(str(env[option])))
+    val = env[option]
+    if isinstance(val, bool):
+        # Force value to 0/1
+        val = int(val)
+    elif isinstance(val, str):
+        val = '"' + val + '"'
+        
     # Sources are option name & value (packaged in SCons Value nodes)
     return ([target], [Value(option), Value(val)])
 

src/sim/main.cc

@@ -55,6 +55,7 @@
 #include "base/statistics.hh"
 #include "base/str.hh"
 #include "base/time.hh"
+#include "config/pythonhome.hh"
 #include "cpu/base.hh"
 #include "cpu/smt.hh"
 #include "mem/mem_object.hh"
@@ -145,6 +146,11 @@ main(int argc, char **argv)
     if (setenv("PYTHONPATH", pythonpath.c_str(), true) == -1)
         fatal("setenv: %s\n", strerror(errno));
 
+    char *python_home = getenv("PYTHONHOME");
+    if (!python_home)
+        python_home = PYTHONHOME;
+    Py_SetPythonHome(python_home);
+
     // initialize embedded Python interpreter
     Py_Initialize();
     PySys_SetArgv(argc, argv);