diff --git a/byterun/Makefile b/byterun/Makefile
index 68aa02e7c..1f99d9c87 100644
--- a/byterun/Makefile
+++ b/byterun/Makefile
@@ -1,7 +1,7 @@
 include ../config/Makefile
 
 CC=$(BYTECC)
-CFLAGS=-O $(BYTECCCOMPOPTS)
+CFLAGS=-O $(BYTECCCOMPOPTS) -DBC_PROFILE
 DFLAGS=-g -DDEBUG $(BYTECCCOMPOPTS)
 
 OBJS=interp.o misc.o stacks.o fix_code.o startup.o main.o \
diff --git a/byterun/config.h b/byterun/config.h
index f93f2f444..a212b296b 100644
--- a/byterun/config.h
+++ b/byterun/config.h
@@ -36,7 +36,7 @@
 /* We use threaded code interpretation if the compiler provides labels
    as first-class values (GCC 2.x). */
 
-#if defined(__GNUC__) && __GNUC__ >= 2 && !defined(DEBUG)
+#if defined(__GNUC__) && __GNUC__ >= 2 && !defined(DEBUG) && !defined(BC_PROFILE)
 #define THREADED_CODE
 #endif
 
diff --git a/byterun/interp.c b/byterun/interp.c
index 487f849d1..0b60954bd 100644
--- a/byterun/interp.c
+++ b/byterun/interp.c
@@ -173,6 +173,12 @@ value interprete(prog, prog_size)
     Assert(sp >= stack_low);
     Assert(sp <= stack_high);
 #endif
+#if BC_PROFILE
+    {
+      extern unsigned long bc_counts [];
+      ++ bc_counts [*pc];
+    }
+#endif /* BC_PROFILE */
     switch(*pc++) {
 #endif
 
diff --git a/byterun/startup.c b/byterun/startup.c
index 1388c4a48..599eb784e 100644
--- a/byterun/startup.c
+++ b/byterun/startup.c
@@ -129,6 +129,21 @@ Algorithm:
 
 extern void init_ieee_floats();
 
+#ifdef BC_PROFILE
+unsigned long bc_counts [128];
+void savecounts ()
+{
+  char *countfilename = getenv ("CAML_BC_COUNTFILE");
+
+  if (countfilename != NULL){
+    FILE *countfile = fopen (countfilename, "w");
+    if (countfile != NULL){
+      fwrite (bc_counts, sizeof (unsigned long), 128, countfile);
+    }
+  }
+}
+#endif /* BC_PROFILE */
+
 void caml_main(argc, argv)
      int argc;
      char ** argv;
@@ -150,6 +165,22 @@ void caml_main(argc, argv)
   verbose_init = 1;
 #endif
 
+#ifdef BC_PROFILE
+  {
+    char *countfilename = getenv ("CAML_BC_COUNTFILE");
+    int i;
+
+    if (countfilename != NULL){
+      FILE *countfile = fopen (countfilename, "r");
+      for (i = 0; i < 128; i++) bc_counts [i] = 0;
+      if (countfile != NULL){
+	fread (bc_counts, sizeof (unsigned long), 128, countfile);
+      }
+    }
+    atexit (savecounts);
+  }
+#endif /* BC_PROFILE */
+
   i = 0;
   fd = attempt_open(&argv[0], &trail, 0);