python3: Fix pyc-only related runtime exceptions

Python3 changes the pyc lookup strategy, ignoring the
__pycache__ directory if the .py file is missing. Change
install location to enable use of .pyc without their parent .py

See http://www.python.org/dev/peps/pep-3147

Signed-off-by: Daniel Nelson <daniel@sigpwr.com>

Index: b/configure.ac
===================================================================
--- a/configure.ac
+++ b/configure.ac
@@ -352,6 +352,23 @@
 AC_SUBST(FRAMEWORKUNIXTOOLSPREFIX)
 AC_SUBST(FRAMEWORKINSTALLAPPSPREFIX)
 
+STDLIB_CACHE_FLAGS=
+AC_MSG_CHECKING(for --enable-old-stdlib-cache)
+AC_ARG_ENABLE(old-stdlib-cache,
+    AS_HELP_STRING([--enable-old-stdlib-cache], [enable pre-pep3147 stdlib cache]),
+[
+    if test "$enableval" = "yes"
+    then
+        STDLIB_CACHE_FLAGS="-b"
+    else
+        STDLIB_CACHE_FLAGS="" 
+    fi
+],
+[
+    STDLIB_CACHE_FLAGS="" 
+])
+AC_SUBST(STDLIB_CACHE_FLAGS)
+
 ##AC_ARG_WITH(dyld,
 ##            AS_HELP_STRING([--with-dyld],
 ##                           [Use (OpenStep|Rhapsody) dynamic linker]))
Index: b/Makefile.pre.in
===================================================================
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -162,6 +162,9 @@
 # Options to enable prebinding (for fast startup prior to Mac OS X 10.3)
 OTHER_LIBTOOL_OPT=@OTHER_LIBTOOL_OPT@
 
+# Option to enable old-style precompiled stdlib
+STDLIB_CACHE_FLAGS=@STDLIB_CACHE_FLAGS@
+
 # Environment to run shared python without installed libraries
 RUNSHARED=       @RUNSHARED@
 
@@ -1246,21 +1249,21 @@
 	fi
 	-PYTHONPATH=$(DESTDIR)$(LIBDEST)  $(RUNSHARED) \
 		$(PYTHON_FOR_BUILD) -Wi $(DESTDIR)$(LIBDEST)/compileall.py \
-		-d $(LIBDEST) -f \
+		-d $(LIBDEST) -f $(STDLIB_CACHE_FLAGS) \
 		-x 'bad_coding|badsyntax|site-packages|lib2to3/tests/data' \
 		$(DESTDIR)$(LIBDEST)
 	-PYTHONPATH=$(DESTDIR)$(LIBDEST) $(RUNSHARED) \
 		$(PYTHON_FOR_BUILD) -Wi -O $(DESTDIR)$(LIBDEST)/compileall.py \
-		-d $(LIBDEST) -f \
+		-d $(LIBDEST) -f $(STDLIB_CACHE_FLAGS) \
 		-x 'bad_coding|badsyntax|site-packages|lib2to3/tests/data' \
 		$(DESTDIR)$(LIBDEST)
 	-PYTHONPATH=$(DESTDIR)$(LIBDEST)  $(RUNSHARED) \
 		$(PYTHON_FOR_BUILD) -Wi $(DESTDIR)$(LIBDEST)/compileall.py \
-		-d $(LIBDEST)/site-packages -f \
+		-d $(LIBDEST)/site-packages -f $(STDLIB_CACHE_FLAGS) \
 		-x badsyntax $(DESTDIR)$(LIBDEST)/site-packages
 	-PYTHONPATH=$(DESTDIR)$(LIBDEST) $(RUNSHARED) \
 		$(PYTHON_FOR_BUILD) -Wi -O $(DESTDIR)$(LIBDEST)/compileall.py \
-		-d $(LIBDEST)/site-packages -f \
+		-d $(LIBDEST)/site-packages -f $(STDLIB_CACHE_FLAGS) \
 		-x badsyntax $(DESTDIR)$(LIBDEST)/site-packages
 	-PYTHONPATH=$(DESTDIR)$(LIBDEST) $(RUNSHARED) \
 		$(PYTHON_FOR_BUILD) -m lib2to3.pgen2.driver $(DESTDIR)$(LIBDEST)/lib2to3/Grammar.txt