diff -rupN ruby-1.8.7-p334.orig/common.mk ruby-1.8.7-p334/common.mk
--- ruby-1.8.7-p334.orig/common.mk	2011-04-12 15:28:51.099921336 -0700
+++ ruby-1.8.7-p334/common.mk	2011-04-12 15:25:22.224376846 -0700
@@ -55,6 +55,7 @@ OBJS	      = array.$(OBJEXT) \
 		string.$(OBJEXT) \
 		struct.$(OBJEXT) \
 		time.$(OBJEXT) \
+		tracer.$(OBJEXT) \
 		util.$(OBJEXT) \
 		variable.$(OBJEXT) \
 		version.$(OBJEXT) \
@@ -85,9 +86,9 @@ prog: $(PROGRAM) $(WPROGRAM)
 
 miniruby$(EXEEXT): config.status $(LIBRUBY_A) $(MAINOBJ) $(MINIOBJS) $(OBJS) $(DMYEXT)
 
-$(PROGRAM): $(LIBRUBY) $(MAINOBJ) $(OBJS) $(EXTOBJS) $(SETUP) $(PREP)
+$(PROGRAM): $(LIBRUBY) $(MAINOBJ) $(OBJS) $(EXTOBJS) $(DTRACE_OBJS) $(SETUP) $(PREP)
 
-$(LIBRUBY_A):	$(OBJS) $(DMYEXT) $(ARCHFILE)
+$(LIBRUBY_A):	$(OBJS) $(DMYEXT) $(ARCHFILE) $(DTRACE_OBJS)
 
 $(LIBRUBY_SO):	$(OBJS) $(DLDOBJS) $(LIBRUBY_A) $(PREP) $(LIBRUBY_SO_UPDATE)
 
@@ -280,7 +281,7 @@ clear-installed-list:
 
 clean: clean-ext clean-local
 clean-local::
-	@$(RM) $(OBJS) $(MINIOBJS) $(MAINOBJ) $(LIBRUBY_A) $(LIBRUBY_SO) $(LIBRUBY) $(LIBRUBY_ALIASES)
+	@$(RM) $(OBJS) $(DTRACE_OBJS) $(MINIOBJS) $(MAINOBJ) $(LIBRUBY_A) $(LIBRUBY_SO) $(LIBRUBY) $(LIBRUBY_ALIASES)
 	@$(RM) $(PROGRAM) $(WPROGRAM) miniruby$(EXEEXT) dmyext.$(OBJEXT) $(ARCHFILE) .*.time
 	@$(RM) y.tab.c y.output
 clean-ext:
diff -rupN ruby-1.8.7-p334.orig/configure.in ruby-1.8.7-p334/configure.in
--- ruby-1.8.7-p334.orig/configure.in	2011-04-12 15:28:51.101489810 -0700
+++ ruby-1.8.7-p334/configure.in	2011-04-12 15:43:06.096160692 -0700
@@ -524,6 +524,11 @@ AC_CHECK_HEADERS(stdlib.h string.h unist
 		 sys/mkdev.h sys/utime.h netinet/in_systm.h float.h ieeefp.h pthread.h \
 		 ucontext.h intrinsics.h time.h)
 
+AC_CHECK_HEADER(sys/sdt.h)
+if test "$ac_cv_header_sys_sdt_h" == "yes"; then
+	AC_DEFINE(HAVE_SDT_H)
+fi
+
 dnl Check additional types.
 AC_CHECK_SIZEOF(rlim_t, 0, [
   #ifdef HAVE_SYS_TYPES_H
@@ -698,6 +703,18 @@ if test "$use_setreuid" = yes; then
     AC_DEFINE(USE_SETREUID)
     AC_DEFINE(USE_SETREGID)
 fi
+
+AC_ARG_ENABLE(dtrace,
+	[  --enable-dtrace         enable DTrace support.],
+	[enable_dtrace=$enableval])
+if test "$enable_dtrace" == "yes" -a "$ac_cv_header_sys_sdt_h" == "yes"; then
+	AC_DEFINE(ENABLE_DTRACE)
+	DTRACE_OBJS="dtrace.o"
+else
+	DTRACE_OBJS=""
+fi
+AC_SUBST(DTRACE_OBJS)
+
 AC_STRUCT_TIMEZONE
 AC_CACHE_CHECK(for struct tm.tm_gmtoff, rb_cv_member_struct_tm_tm_gmtoff,
   [AC_TRY_COMPILE([#include <time.h>],
@@ -1207,7 +1224,7 @@
 	 		       LDFLAGS="$LDFLAGS -Wl,-E"
 			   fi
 			else
-			   : ${LDSHARED='ld -G'}
+			   : ${LDSHARED='$(CC) -G'}
 			fi
 			rb_cv_dlopen=yes;;
 	sunos*) 	: ${LDSHARED='ld -assert nodefinitions'}
diff -rupN ruby-1.8.7-p334.orig/dtrace.d ruby-1.8.7-p334/dtrace.d
--- ruby-1.8.7-p334.orig/dtrace.d	1969-12-31 16:00:00.000000000 -0800
+++ ruby-1.8.7-p334/dtrace.d	2011-04-12 15:25:22.224285683 -0700
@@ -0,0 +1,26 @@
+/* -*- Mode: C -*- */
+
+provider ruby {
+    probe function__entry(char*, char*, char*, int);
+    probe function__return(char*, char*, char*, int);
+    probe raise(char*, char*, int);
+    probe rescue(char*, int);
+    probe line(char*, int);
+
+    /* gc probes */
+    probe gc__begin();
+    probe gc__end();
+
+    /* Some initial memory type probes */
+    probe object__create__start(char*, char*, int);
+    probe object__create__done(char*, char*, int);
+    probe object__free(char*);
+
+    probe ruby__probe(char*, char*);
+};
+
+#pragma D attributes Evolving/Evolving/Common provider ruby provider
+#pragma D attributes Private/Private/Common provider ruby module
+#pragma D attributes Private/Private/Common provider ruby function
+#pragma D attributes Evolving/Evolving/Common provider ruby name
+#pragma D attributes Evolving/Evolving/Common provider ruby args
diff -rupN ruby-1.8.7-p334.orig/dtrace.h ruby-1.8.7-p334/dtrace.h
--- ruby-1.8.7-p334.orig/dtrace.h	1969-12-31 16:00:00.000000000 -0800
+++ ruby-1.8.7-p334/dtrace.h	2011-04-12 15:25:22.224323302 -0700
@@ -0,0 +1,85 @@
+/*
+ * Generated by dtrace(1M).
+ */
+
+#ifndef	_DTRACE_H
+#define	_DTRACE_H
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+#define	RUBY_FUNCTION_ENTRY(arg0, arg1, arg2, arg3) \
+	__dtrace_ruby___function__entry(arg0, arg1, arg2, arg3)
+#define	RUBY_FUNCTION_ENTRY_ENABLED() \
+	__dtraceenabled_ruby___function__entry()
+#define	RUBY_FUNCTION_RETURN(arg0, arg1, arg2, arg3) \
+	__dtrace_ruby___function__return(arg0, arg1, arg2, arg3)
+#define	RUBY_FUNCTION_RETURN_ENABLED() \
+	__dtraceenabled_ruby___function__return()
+#define	RUBY_GC_BEGIN() \
+	__dtrace_ruby___gc__begin()
+#define	RUBY_GC_BEGIN_ENABLED() \
+	__dtraceenabled_ruby___gc__begin()
+#define	RUBY_GC_END() \
+	__dtrace_ruby___gc__end()
+#define	RUBY_GC_END_ENABLED() \
+	__dtraceenabled_ruby___gc__end()
+#define	RUBY_LINE(arg0, arg1) \
+	__dtrace_ruby___line(arg0, arg1)
+#define	RUBY_LINE_ENABLED() \
+	__dtraceenabled_ruby___line()
+#define	RUBY_OBJECT_CREATE_DONE(arg0, arg1, arg2) \
+	__dtrace_ruby___object__create__done(arg0, arg1, arg2)
+#define	RUBY_OBJECT_CREATE_DONE_ENABLED() \
+	__dtraceenabled_ruby___object__create__done()
+#define	RUBY_OBJECT_CREATE_START(arg0, arg1, arg2) \
+	__dtrace_ruby___object__create__start(arg0, arg1, arg2)
+#define	RUBY_OBJECT_CREATE_START_ENABLED() \
+	__dtraceenabled_ruby___object__create__start()
+#define	RUBY_OBJECT_FREE(arg0) \
+	__dtrace_ruby___object__free(arg0)
+#define	RUBY_OBJECT_FREE_ENABLED() \
+	__dtraceenabled_ruby___object__free()
+#define	RUBY_RAISE(arg0, arg1, arg2) \
+	__dtrace_ruby___raise(arg0, arg1, arg2)
+#define	RUBY_RAISE_ENABLED() \
+	__dtraceenabled_ruby___raise()
+#define	RUBY_RESCUE(arg0, arg1) \
+	__dtrace_ruby___rescue(arg0, arg1)
+#define	RUBY_RESCUE_ENABLED() \
+	__dtraceenabled_ruby___rescue()
+#define	RUBY_RUBY_PROBE(arg0, arg1) \
+	__dtrace_ruby___ruby__probe(arg0, arg1)
+#define	RUBY_RUBY_PROBE_ENABLED() \
+	__dtraceenabled_ruby___ruby__probe()
+
+
+extern void __dtrace_ruby___function__entry(char *, char *, char *, int);
+extern int __dtraceenabled_ruby___function__entry(void);
+extern void __dtrace_ruby___function__return(char *, char *, char *, int);
+extern int __dtraceenabled_ruby___function__return(void);
+extern void __dtrace_ruby___gc__begin(void);
+extern int __dtraceenabled_ruby___gc__begin(void);
+extern void __dtrace_ruby___gc__end(void);
+extern int __dtraceenabled_ruby___gc__end(void);
+extern void __dtrace_ruby___line(char *, int);
+extern int __dtraceenabled_ruby___line(void);
+extern void __dtrace_ruby___object__create__done(char *, char *, int);
+extern int __dtraceenabled_ruby___object__create__done(void);
+extern void __dtrace_ruby___object__create__start(char *, char *, int);
+extern int __dtraceenabled_ruby___object__create__start(void);
+extern void __dtrace_ruby___object__free(char *);
+extern int __dtraceenabled_ruby___object__free(void);
+extern void __dtrace_ruby___raise(char *, char *, int);
+extern int __dtraceenabled_ruby___raise(void);
+extern void __dtrace_ruby___rescue(char *, int);
+extern int __dtraceenabled_ruby___rescue(void);
+extern void __dtrace_ruby___ruby__probe(char *, char *);
+extern int __dtraceenabled_ruby___ruby__probe(void);
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif	/* _DTRACE_H */
diff -rupN ruby-1.8.7-p334.orig/eval.c ruby-1.8.7-p334/eval.c
--- ruby-1.8.7-p334.orig/eval.c	2011-04-12 15:28:51.209420258 -0700
+++ ruby-1.8.7-p334/eval.c	2011-04-12 15:25:22.224969993 -0700
@@ -226,6 +226,10 @@ int _setjmp(), _longjmp();
 
 #include <sys/stat.h>
 
+#ifdef ENABLE_DTRACE
+#include "dtrace.h"
+#endif
+
 VALUE rb_cProc;
 VALUE rb_cBinding;
 static VALUE proc_invoke _((VALUE,VALUE,VALUE,VALUE));
@@ -3059,12 +3063,22 @@ rb_eval(self, n)
 
       case NODE_IF:
 	if (RTEST(rb_eval(self, node->nd_cond))) {
+	    #ifdef ENABLE_DTRACE
+	    if (RUBY_LINE_ENABLED())
+		if (ruby_current_node && ruby_current_node->nd_file)
+		    RUBY_LINE(ruby_current_node->nd_file, nd_line(ruby_current_node));
+	    #endif
 	    EXEC_EVENT_HOOK(RUBY_EVENT_LINE, node, self,
 			    ruby_frame->last_func,
 			    ruby_frame->last_class);
 	    node = node->nd_body;
 	}
 	else {
+	    #ifdef ENABLE_DTRACE
+	    if (RUBY_LINE_ENABLED())
+		if (ruby_current_node && ruby_current_node->nd_file)
+		    RUBY_LINE(ruby_current_node->nd_file, nd_line(ruby_current_node));
+	    #endif
 	    EXEC_EVENT_HOOK(RUBY_EVENT_LINE, node, self,
 			    ruby_frame->last_func,
 			    ruby_frame->last_class);
@@ -3079,6 +3093,11 @@ rb_eval(self, n)
 	    if (nd_type(node) != NODE_WHEN) goto again;
 	    tag = node->nd_head;
 	    while (tag) {
+		#ifdef ENABLE_DTRACE
+		if (RUBY_LINE_ENABLED())
+		    if (ruby_current_node && ruby_current_node->nd_file)
+			RUBY_LINE(ruby_current_node->nd_file, nd_line(ruby_current_node));
+		#endif
 		EXEC_EVENT_HOOK(RUBY_EVENT_LINE, tag, self,
 				ruby_frame->last_func,
 				ruby_frame->last_class);
@@ -3120,6 +3139,11 @@ rb_eval(self, n)
 		}
 		tag = node->nd_head;
 		while (tag) {
+		    #ifdef ENABLE_DTRACE
+		    if (RUBY_LINE_ENABLED())
+		        if (ruby_current_node && ruby_current_node->nd_file)
+			    RUBY_LINE(ruby_current_node->nd_file, nd_line(ruby_current_node));
+		    #endif
 		    EXEC_EVENT_HOOK(RUBY_EVENT_LINE, tag, self,
 				    ruby_frame->last_func,
 				    ruby_frame->last_class);
@@ -3340,6 +3364,11 @@ rb_eval(self, n)
 		rescuing = -1;
 		while (resq) {
 		    ruby_current_node = resq;
+		    #ifdef ENABLE_DTRACE
+		    if (RUBY_RESCUE_ENABLED())
+		        if (ruby_current_node && ruby_current_node->nd_file)
+			RUBY_RESCUE(ruby_current_node->nd_file, nd_line(ruby_current_node));
+		    #endif
 		    if (handle_rescue(self, resq)) {
 			state = 0;
 			rescuing = 1;
@@ -4160,6 +4189,11 @@ rb_eval(self, n)
 	break;
 
       case NODE_NEWLINE:
+	#ifdef ENABLE_DTRACE
+	if (RUBY_LINE_ENABLED())
+	    if (ruby_current_node && ruby_current_node->nd_file)
+		RUBY_LINE(ruby_current_node->nd_file, nd_line(ruby_current_node));
+	#endif
 	EXEC_EVENT_HOOK(RUBY_EVENT_LINE, node, self, 
 			ruby_frame->last_func,
 			ruby_frame->last_class);
@@ -4638,6 +4672,10 @@ rb_longjmp(tag, mesg)
 
     rb_trap_restore_mask();
     if (tag != TAG_FATAL) {
+	#ifdef ENABLE_DTRACE
+	if (RUBY_RAISE_ENABLED())
+	    RUBY_RAISE(rb_obj_classname(ruby_errinfo), ruby_sourcefile, ruby_sourceline);
+	#endif
 	EXEC_EVENT_HOOK(RUBY_EVENT_RAISE, ruby_current_node,
 			ruby_frame->self,
 			ruby_frame->last_func,
@@ -5909,6 +5947,13 @@ rb_call0(klass, recv, id, oid, argc, arg
 		rb_bug("bad argc (%d) specified for `%s(%s)'",
 		       len, rb_class2name(klass), rb_id2name(id));
 	    }
+    	    #ifdef ENABLE_DTRACE
+	    if (RUBY_FUNCTION_ENTRY_ENABLED()) {
+	    	    char *classname = rb_class2name(klass), *methodname = rb_id2name(id);
+		    if (ruby_current_node && ruby_current_node->nd_file && classname && methodname)
+			RUBY_FUNCTION_ENTRY(classname, methodname, ruby_current_node->nd_file, nd_line(ruby_current_node));
+	    }
+	    #endif
 	    if (event_hooks) {
 		int state;
 
@@ -5927,6 +5972,13 @@ rb_call0(klass, recv, id, oid, argc, arg
 	    else {
 		result = call_cfunc(body->nd_cfnc, recv, len, argc, argv);
 	    }
+	    #ifdef ENABLE_DTRACE
+    	    if (RUBY_FUNCTION_RETURN_ENABLED()) {
+	        char *classname = rb_class2name(klass), *methodname = rb_id2name(id);
+	        if (ruby_current_node && ruby_current_node->nd_file && classname && methodname)
+	            RUBY_FUNCTION_RETURN(classname, methodname, ruby_current_node->nd_file, nd_line(ruby_current_node));			
+	    }
+	    #endif
 	}
 	break;
 
@@ -5954,12 +6006,26 @@ rb_call0(klass, recv, id, oid, argc, arg
 
       case NODE_BMETHOD:
 	ruby_frame->flags |= FRAME_DMETH;
+	#ifdef ENABLE_DTRACE
+	if (RUBY_FUNCTION_ENTRY_ENABLED()) {
+		char *classname = rb_class2name(klass), *methodname = rb_id2name(id);
+		if (ruby_current_node && ruby_current_node->nd_file && classname && methodname)
+	            RUBY_FUNCTION_ENTRY(classname, methodname, ruby_current_node->nd_file, nd_line(ruby_current_node));
+	 }
+	#endif
 	if (event_hooks) {
 	    struct BLOCK *data;
 	    Data_Get_Struct(body->nd_cval, struct BLOCK, data);
 	    EXEC_EVENT_HOOK(RUBY_EVENT_CALL, data->body, recv, id, klass);
 	}
 	result = proc_invoke(body->nd_cval, rb_ary_new4(argc, argv), recv, klass);
+	#ifdef ENABLE_DTRACE
+	 if (RUBY_FUNCTION_RETURN_ENABLED()) {
+	    char *classname = rb_class2name(klass), *methodname = rb_id2name(id);
+	    if (ruby_current_node && ruby_current_node->nd_file && classname && methodname)
+	        RUBY_FUNCTION_RETURN(classname, methodname, ruby_current_node->nd_file, nd_line(ruby_current_node));
+	}
+	#endif
 	if (event_hooks) {
 	    EXEC_EVENT_HOOK(RUBY_EVENT_RETURN, ruby_current_node, recv, id, klass);
 	}
@@ -6073,6 +6139,13 @@ rb_call0(klass, recv, id, oid, argc, arg
 		    }
 		    ruby_frame->argc = i;
 		}
+		#ifdef ENABLE_DTRACE
+		if (RUBY_FUNCTION_ENTRY_ENABLED()) {
+			char *classname = rb_class2name(klass), *methodname = rb_id2name(id);
+			if (ruby_current_node && ruby_current_node->nd_file && classname && methodname)
+		            RUBY_FUNCTION_ENTRY(classname, methodname, ruby_current_node->nd_file, nd_line(ruby_current_node));
+		 }
+		#endif
 		if (event_hooks) {
 		    EXEC_EVENT_HOOK(RUBY_EVENT_CALL, b2, recv, id, klass);
 		}
@@ -6083,6 +6156,13 @@ rb_call0(klass, recv, id, oid, argc, arg
 		state = 0;
 	    }
 	    POP_TAG();
+	    #ifdef ENABLE_DTRACE
+	     if (RUBY_FUNCTION_RETURN_ENABLED()) {
+		char *classname = rb_class2name(klass), *methodname = rb_id2name(id);
+		if (ruby_current_node && ruby_current_node->nd_file && classname && methodname)
+	 	    RUBY_FUNCTION_RETURN(classname, methodname, ruby_current_node->nd_file, nd_line(ruby_current_node));
+	    }
+	    #endif
 	    if (event_hooks) {
 		EXEC_EVENT_HOOK(RUBY_EVENT_RETURN, ruby_current_node, recv, id, klass);
 	    }
diff -rupN ruby-1.8.7-p334.orig/gc.c ruby-1.8.7-p334/gc.c
--- ruby-1.8.7-p334.orig/gc.c	2011-04-12 15:28:51.239680123 -0700
+++ ruby-1.8.7-p334/gc.c	2011-04-12 15:25:22.225120360 -0700
@@ -30,6 +30,11 @@
 #include <sys/resource.h>
 #endif
 
+#ifdef ENABLE_DTRACE
+#include <sys/sdt.h>
+#include "dtrace.h"
+#endif
+
 #if defined _WIN32 || defined __CYGWIN__
 #include <windows.h>
 #endif
@@ -1264,6 +1269,11 @@ obj_free(obj)
 	break;
     }
 
+   #ifdef ENABLE_DTRACE
+   if (RUBY_OBJECT_FREE_ENABLED())
+      RUBY_OBJECT_FREE(rb_class2name(CLASS_OF(obj)));
+   #endif
+
     if (FL_TEST(obj, FL_EXIVAR)) {
 	rb_free_generic_ivar((VALUE)obj);
     }
@@ -1430,6 +1440,12 @@ garbage_collect()
 {
     struct gc_list *list;
     struct FRAME * volatile frame; /* gcc 2.7.2.3 -O2 bug??  */
+
+    #ifdef ENABLE_DTRACE
+    if (RUBY_GC_BEGIN_ENABLED())
+       RUBY_GC_BEGIN();
+    #endif
+
     jmp_buf save_regs_gc_mark;
     SET_STACK_END;
 
@@ -1522,6 +1538,11 @@ garbage_collect()
     } while (!MARK_STACK_EMPTY);
 
     gc_sweep();
+
+    #ifdef ENABLE_DTRACE
+    if (RUBY_GC_END_ENABLED())
+	RUBY_GC_END();
+    #endif
 }
 
 void
diff -rupN ruby-1.8.7-p334.orig/inits.c ruby-1.8.7-p334/inits.c
--- ruby-1.8.7-p334.orig/inits.c	2011-04-12 15:28:51.287011653 -0700
+++ ruby-1.8.7-p334/inits.c	2011-04-12 14:50:21.714050708 -0700
@@ -46,6 +46,7 @@ void Init_Struct _((void));
 void Init_Time _((void));
 void Init_var_tables _((void));
 void Init_version _((void));
+void Init_Tracer _((void));
 
 void
 rb_call_inits()
@@ -83,4 +84,5 @@ rb_call_inits()
     Init_Enumerator();
     Init_marshal();
     Init_version();
+    Init_Tracer();
 }
diff -rupN ruby-1.8.7-p334.orig/Makefile.in ruby-1.8.7-p334/Makefile.in
--- ruby-1.8.7-p334.orig/Makefile.in	2011-04-12 15:27:29.001372251 -0700
+++ ruby-1.8.7-p334/Makefile.in	2011-04-12 15:33:29.186318522 -0700
@@ -88,6 +88,7 @@ ASFLAGS       = @ASFLAGS@
 
 OBJEXT        = @OBJEXT@
 MANTYPE	      = @MANTYPE@
+DTRACE_OBJS   = @DTRACE_OBJS@
 
 INSTALLED_LIST= .installed.list
 #### End of variables
@@ -103,11 +104,11 @@ all:
 
 miniruby$(EXEEXT):
 		@$(RM) $@
-		$(PURIFY) $(CC) $(LDFLAGS) $(XLDFLAGS) $(MAINLIBS) $(MAINOBJ) $(MINIOBJS) $(LIBRUBY_A) $(LIBS) $(OUTFLAG)$@
+		$(PURIFY) $(CC) $(LDFLAGS) $(XLDFLAGS) $(MAINLIBS) $(MAINOBJ) $(MINIOBJS) $(LIBRUBY_A) $(DTRACE_OBJS) $(LIBS) $(OUTFLAG)$@
 
 $(PROGRAM):
 		@$(RM) $@
-		$(PURIFY) $(CC) $(LDFLAGS) $(XLDFLAGS) $(MAINLIBS) $(MAINOBJ) $(EXTOBJS) $(LIBRUBYARG) $(LIBS) $(OUTFLAG)$@
+		$(PURIFY) $(CC) $(LDFLAGS) $(XLDFLAGS) $(MAINLIBS) $(MAINOBJ) $(EXTOBJS) $(DTRACE_OBJS) gc.o eval.o tracer.o $(LIBRUBYARG) $(LIBS) $(OUTFLAG)$@
 
 # We must `rm' the library each time this rule is invoked because "updating" a
 # MAB library on Apple/NeXT (see --enable-fat-binary in configure) is not
@@ -119,7 +120,7 @@ $(LIBRUBY_A):
 
 $(LIBRUBY_SO):
 		@-$(PRE_LIBRUBY_UPDATE)
-		$(LDSHARED) $(DLDFLAGS) $(OBJS) $(DLDOBJS) $(SOLIBS) $(OUTFLAG)$@
+		$(LDSHARED) $(DLDFLAGS) $(OBJS) $(DLDOBJS) $(DTRACE_OBJS) $(SOLIBS) $(OUTFLAG)$@
 		@-$(MINIRUBY) -e 'ARGV.each{|link| File.delete link if File.exist? link; \
 						  File.symlink "$(LIBRUBY_SO)", link}' \
 				$(LIBRUBY_ALIASES) || true
@@ -194,6 +195,9 @@ distclean-local::
 ext/extinit.$(OBJEXT): ext/extinit.c $(SETUP)
 	$(CC) $(CFLAGS) $(XCFLAGS) $(CPPFLAGS) $(OUTFLAG)$@ -c ext/extinit.c
 
+dtrace.@OBJEXT@: dtrace.d $(OBJS) $(MAINOBJ)
+	/usr/sbin/dtrace -G -o $@ -s dtrace.d $(OBJS)
+
 update-rubyspec: 
 	if [ -d $(srcdir)/rubyspec ]; then \
 	  cd $(srcdir)/rubyspec/mspec; \
diff -rupN ruby-1.8.7-p334.orig/object.c ruby-1.8.7-p334/object.c
--- ruby-1.8.7-p334.orig/object.c	2011-04-12 15:28:51.288940374 -0700
+++ ruby-1.8.7-p334/object.c	2011-04-12 15:25:22.224228022 -0700
@@ -20,6 +20,12 @@
 #include <ctype.h>
 #include <math.h>
 
+#ifdef ENABLE_DTRACE
+#include "dtrace.h"
+#include "node.h"
+NODE* ruby_current_node;
+#endif
+
 VALUE rb_mKernel;
 VALUE rb_cObject;
 VALUE rb_cModule;
@@ -1603,7 +1609,25 @@ rb_obj_alloc(klass)
     if (FL_TEST(klass, FL_SINGLETON)) {
 	rb_raise(rb_eTypeError, "can't create instance of virtual class");
     }
+
+    #ifdef ENABLE_DTRACE
+    if (RUBY_OBJECT_CREATE_START_ENABLED()) {
+	char *file = ruby_current_node == NULL ? "" : ruby_current_node->nd_file;
+	int   line = ruby_current_node == NULL ? 0  : nd_line(ruby_current_node);
+	RUBY_OBJECT_CREATE_START(rb_class2name(klass), file, line);
+    }
+    #endif
+
     obj = rb_funcall(klass, ID_ALLOCATOR, 0, 0);
+
+    #ifdef ENABLE_DTRACE
+    if (RUBY_OBJECT_CREATE_DONE_ENABLED()) {
+	char *file = ruby_current_node == NULL ? "" : ruby_current_node->nd_file;
+	int   line = ruby_current_node == NULL ? 0  : nd_line(ruby_current_node);
+	RUBY_OBJECT_CREATE_DONE(rb_class2name(klass), file, line);
+    }
+    #endif
+
     if (rb_obj_class(obj) != rb_class_real(klass)) {
 	rb_raise(rb_eTypeError, "wrong instance allocation");
     }
diff -rupN ruby-1.8.7-p334.orig/tracer.c ruby-1.8.7-p334/tracer.c
--- ruby-1.8.7-p334.orig/tracer.c	1969-12-31 16:00:00.000000000 -0800
+++ ruby-1.8.7-p334/tracer.c	2011-04-12 14:53:16.013377766 -0700
@@ -0,0 +1,64 @@
+#include "ruby.h"
+
+#ifdef ENABLE_DTRACE
+#include "dtrace.h"
+#endif
+
+VALUE rb_mDtrace;
+
+static VALUE
+ruby_dtrace_fire(argc, argv, klass)
+  int argc;
+  VALUE *argv;
+  VALUE klass;
+{
+	int args;
+	VALUE name, data, ret;
+	char *probe_data;
+	char *probe_name;
+	char *start_probe;
+	char *end_probe;
+	
+	#ifdef ENABLE_DTRACE
+
+	args = rb_scan_args(argc, argv, "11", &name, &data);
+	probe_data = args == 2 ? StringValuePtr(data) : "";
+	probe_name = StringValuePtr(name);
+
+    	if (rb_block_given_p()) {
+		start_probe = malloc(strlen(probe_name) + 7);
+		end_probe   = malloc(strlen(probe_name) + 5);
+		
+		sprintf(start_probe, "%s-start", probe_name);
+		sprintf(end_probe, "%s-end", probe_name);
+		
+		/* Build -start and -end strings for probe names */
+		if (RUBY_RUBY_PROBE_ENABLED())
+			RUBY_RUBY_PROBE(start_probe, probe_data);
+	#endif
+	
+		ret = rb_yield(Qnil);
+	
+	#if ENABLE_DTRACE
+
+		if (RUBY_RUBY_PROBE_ENABLED())
+			RUBY_RUBY_PROBE(end_probe, probe_data);
+		
+		free(start_probe);
+		free(end_probe);
+    	} else {
+		if (RUBY_RUBY_PROBE_ENABLED())
+			RUBY_RUBY_PROBE(probe_name, probe_data);
+		ret = Qnil;
+	}
+	#endif
+    	return ret;
+}
+
+
+void Init_Tracer()
+{
+	rb_mDtrace = rb_define_module("DTracer");
+	rb_define_module_function(rb_mDtrace, "fire", ruby_dtrace_fire, -1);
+}
+
