diff --git a/Include/pythonrun.h b/Include/pythonrun.h
index 94413768110..6c6117bfe49 100644
--- a/Include/pythonrun.h
+++ b/Include/pythonrun.h
@@ -42,6 +42,8 @@ object *run_file PROTO((FILE *, char *, int, object *, object *));
 object *run_err_node PROTO((int, struct _node *, char *, object *, object *));
 object *run_node PROTO((struct _node *, char *, object *, object *));
 
+object *compile_string PROTO((char *, char *, int));
+
 void print_error PROTO((void));
 
 void goaway PROTO((int));
diff --git a/Objects/frameobject.c b/Objects/frameobject.c
index 85c89f6562a..aa2979577e7 100644
--- a/Objects/frameobject.c
+++ b/Objects/frameobject.c
@@ -38,7 +38,7 @@ static struct memberlist frame_memberlist[] = {
 	{"f_code",	T_OBJECT,	OFF(f_code)},
 	{"f_globals",	T_OBJECT,	OFF(f_globals)},
 	{"f_locals",	T_OBJECT,	OFF(f_locals)},
-	{"f_fastlocals",T_OBJECT,	OFF(f_fastlocals)},
+/*	{"f_fastlocals",T_OBJECT,	OFF(f_fastlocals)}, /* XXX Unsafe */
 	{"f_localmap",	T_OBJECT,	OFF(f_localmap)},
 	{"f_lasti",	T_INT,		OFF(f_lasti)},
 	{"f_lineno",	T_INT,		OFF(f_lineno)},
diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index 8fd12e41927..b74b9cc0282 100644
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -35,6 +35,8 @@ OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #include "pythonrun.h"
 #include "ceval.h"
 #include "modsupport.h"
+#include "compile.h"
+#include "eval.h"
 
 static object *
 builtin_abs(self, v)
@@ -106,6 +108,29 @@ builtin_coerce(self, args)
 	return res;
 }
 
+static object *
+builtin_compile(self, args)
+	object *self;
+	object *args;
+{
+	char *str;
+	char *filename;
+	char *startstr;
+	int start;
+	if (!getargs(args, "(sss)", &str, &filename, &startstr))
+		return NULL;
+	if (strcmp(startstr, "exec") == 0)
+		start = file_input;
+	else if (strcmp(startstr, "eval") == 0)
+		start = eval_input;
+	else {
+		err_setstr(ValueError,
+			   "compile() mode must be 'exec' or 'eval'");
+		return NULL;
+	}
+	return compile_string(str, filename, start);
+}
+
 static object *
 builtin_dir(self, v)
 	object *self;
@@ -168,23 +193,26 @@ exec_eval(v, start)
 	char *s;
 	int n;
 	if (v != NULL) {
-		if (is_stringobject(v))
-			str = v;
-		else if (is_tupleobject(v) &&
+		if (is_tupleobject(v) &&
 				((n = gettuplesize(v)) == 2 || n == 3)) {
 			str = gettupleitem(v, 0);
 			globals = gettupleitem(v, 1);
 			if (n == 3)
 				locals = gettupleitem(v, 2);
 		}
+		else
+			str = v;
 	}
-	if (str == NULL || !is_stringobject(str) ||
+	if (str == NULL || (!is_stringobject(str) && !is_codeobject(str)) ||
 			globals != NULL && !is_dictobject(globals) ||
 			locals != NULL && !is_dictobject(locals)) {
 		err_setstr(TypeError,
-		    "exec/eval arguments must be string[,dict[,dict]]");
+		    "exec/eval arguments must be (string|code)[,dict[,dict]]");
 		return NULL;
 	}
+	if (is_codeobject(str))
+		return eval_code((codeobject *) str, globals, locals,
+				 (object *)NULL);
 	s = getstringvalue(str);
 	if (strlen(s) != getstringsize(str)) {
 		err_setstr(ValueError, "embedded '\\0' in string arg");
@@ -305,6 +333,17 @@ builtin_hasattr(self, args)
 	return newintobject(1L);
 }
 
+static object *
+builtin_id(self, args)
+	object *self;
+	object *args;
+{
+	object *v;
+	if (!getargs(args, "O", &v))
+		return NULL;
+	return newintobject((long)v);
+}
+
 static object *
 builtin_setattr(self, args)
 	object *self;
@@ -713,6 +752,7 @@ static struct methodlist builtin_methods[] = {
 	{"chr",		builtin_chr},
 	{"cmp",		builtin_cmp},
 	{"coerce",	builtin_coerce},
+	{"compile",	builtin_compile},
 	{"dir",		builtin_dir},
 	{"divmod",	builtin_divmod},
 	{"eval",	builtin_eval},
@@ -723,6 +763,7 @@ static struct methodlist builtin_methods[] = {
 	{"hasattr",	builtin_hasattr},
 	{"hash",	builtin_hash},
 	{"hex",		builtin_hex},
+	{"id",		builtin_id},
 	{"input",	builtin_input},
 	{"int",		builtin_int},
 	{"len",		builtin_len},
diff --git a/Python/ceval.c b/Python/ceval.c
index 45d0a6ac41b..cdd71a89d9c 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -45,6 +45,9 @@ OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #define CHECKEXC 1	/* Double-check exception checking */
 #endif
 
+#define DEBUG
+
+
 /* Forward declarations */
 
 #ifdef LLTRACE
@@ -82,6 +85,7 @@ static object *cmp_outcome PROTO((int, object *, object *));
 static int import_from PROTO((object *, object *, object *));
 static object *build_class PROTO((object *, object *));
 static void locals_2_fast PROTO((frameobject *, int));
+static void fast_2_locals PROTO((frameobject *));
 
 
 /* Pointer to current frame, used to link new frames to */
@@ -178,6 +182,7 @@ eval_code(co, globals, locals, arg)
 	object *trace = NULL;	/* Trace function or NULL */
 	object *retval;		/* Return value iff why == WHY_RETURN */
 	char *name;		/* Name used by some instructions */
+	int needmerge = 0;
 #ifdef LLTRACE
 	int lltrace = dictlookup(globals, "__lltrace__") != NULL;
 #endif
@@ -217,6 +222,18 @@ eval_code(co, globals, locals, arg)
 #define POP()		BASIC_POP()
 #endif
 
+	if (globals == NULL) {
+		globals = getglobals();
+		if (locals == NULL) {
+			locals = getlocals();
+			needmerge = 1;
+		}
+	}
+	else {
+		if (locals == NULL)
+			locals = globals;
+	}
+
 	f = newframeobject(
 			current_frame,		/*back*/
 			co,			/*code*/
@@ -1328,11 +1345,17 @@ eval_code(co, globals, locals, arg)
 			why = WHY_EXCEPTION;
 		}
 	}
+
+	if (fastlocals && (f->ob_refcnt > 1 || f->f_locals->ob_refcnt > 2))
+		fast_2_locals(f);
 	
 	/* Restore previous frame and release the current one */
 	
 	current_frame = f->f_back;
 	DECREF(f);
+
+	if (needmerge)
+		locals_2_fast(current_frame, 1);
 	
 	return retval;
 }
@@ -1417,7 +1440,9 @@ call_trace(p_trace, p_newtrace, f, msg, arg)
 	INCREF(arg);
 	settupleitem(arglist, 2, arg);
 	tracing++;
+	fast_2_locals(f);
 	res = call_object(*p_trace, arglist);
+	locals_2_fast(f, 1);
 	tracing--;
  cleanup:
 	XDECREF(arglist);
@@ -1447,24 +1472,25 @@ call_trace(p_trace, p_newtrace, f, msg, arg)
 	}
 }
 
-object *
-getlocals()
-{
-	/* Merge f->f_fastlocals into f->f_locals, then return the latter */
+static void
+fast_2_locals(f)
 	frameobject *f;
+{
+	/* Merge f->f_fastlocals into f->f_locals */
 	object *locals, *fast, *map;
+	object *error_type, *error_value;
 	int i;
-	f = current_frame;
 	if (f == NULL)
-		return NULL;
+		return;
 	locals = f->f_locals;
 	fast = f->f_fastlocals;
 	map = f->f_localmap;
 	if (locals == NULL || fast == NULL || map == NULL)
-		return locals;
+		return;
 	if (!is_dictobject(locals) || !is_listobject(fast) ||
 	    !is_dictobject(map))
-		return locals;
+		return;
+	err_get(&error_type, &error_value);
 	i = getdictsize(map);
 	while (--i >= 0) {
 		object *key;
@@ -1488,7 +1514,7 @@ getlocals()
 				err_clear();
 		}
 	}
-	return locals;
+	err_setval(error_type, error_value);
 }
 
 static void
@@ -1538,6 +1564,15 @@ mergelocals()
 	locals_2_fast(current_frame, 1);
 }
 
+object *
+getlocals()
+{
+	if (current_frame == NULL)
+		return NULL;
+	fast_2_locals(current_frame);
+	return current_frame->f_locals;
+}
+
 object *
 getglobals()
 {
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index c387c629966..98008b4b9ba 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -263,7 +263,7 @@ object *
 run_string(str, start, globals, locals)
 	char *str;
 	int start;
-	/*dict*/object *globals, *locals;
+	object *globals, *locals;
 {
 	node *n;
 	int err;
@@ -276,7 +276,7 @@ run_file(fp, filename, start, globals, locals)
 	FILE *fp;
 	char *filename;
 	int start;
-	/*dict*/object *globals, *locals;
+	object *globals, *locals;
 {
 	node *n;
 	int err;
@@ -289,7 +289,7 @@ run_err_node(err, n, filename, globals, locals)
 	int err;
 	node *n;
 	char *filename;
-	/*dict*/object *globals, *locals;
+	object *globals, *locals;
 {
 	if (err != E_DONE) {
 		err_input(err);
@@ -302,25 +302,9 @@ object *
 run_node(n, filename, globals, locals)
 	node *n;
 	char *filename;
-	/*dict*/object *globals, *locals;
+	object *globals, *locals;
 {
-	object *res;
-	int needmerge = 0;
-	if (globals == NULL) {
-		globals = getglobals();
-		if (locals == NULL) {
-			locals = getlocals();
-			needmerge = 1;
-		}
-	}
-	else {
-		if (locals == NULL)
-			locals = globals;
-	}
-	res = eval_node(n, filename, globals, locals);
-	if (needmerge)
-		mergelocals();
-	return res;
+	return eval_node(n, filename, globals, locals);
 }
 
 object *
@@ -341,6 +325,25 @@ eval_node(n, filename, globals, locals)
 	return v;
 }
 
+object *
+compile_string(str, filename, start)
+	char *str;
+	char *filename;
+	int start;
+{
+	node *n;
+	int err;
+	codeobject *co;
+	err = parse_string(str, start, &n);
+	if (err != E_DONE) {
+		err_input(err);
+		return NULL;
+	}
+	co = compile(n, filename);
+	freetree(n);
+	return (object *)co;
+}
+
 /* Simplified interface to parsefile */
 
 int