additional fields for line numbers added to data segment, codegen generates padding...
[cacao.git] / src / vm / builtin.c
index f3e516257f2749b9a2a3ffb4378274b8f6d2ab9a..aa0165bd6ac284d22195eb506b130206d625b04b 100644 (file)
@@ -34,7 +34,7 @@
    calls instead of machine instructions, using the C calling
    convention.
 
-   $Id: builtin.c 782 2003-12-15 15:47:09Z twisti $
+   $Id: builtin.c 967 2004-03-18 14:29:03Z jowenn $
 
 */
 
 
 #undef DEBUG /*define DEBUG 1*/
 
-/* XXX delete? */
-#if 0
-builtin_descriptor builtin_desc[] = {
-       {(functionptr) builtin_instanceof,                 "instanceof"},
-       {(functionptr) builtin_checkcast,                  "checkcast"},
-       {(functionptr) asm_builtin_checkcast,      "checkcast"},
-       {(functionptr) builtin_arrayinstanceof,    "arrayinstanceof"},
-#if defined(__I386__)
-       {(functionptr) asm_builtin_arrayinstanceof,"arrayinstanceof"},
-#endif
-       {(functionptr) builtin_checkarraycast,     "checkarraycast"},
-       {(functionptr) asm_builtin_checkarraycast, "checkarraycast"},
-       {(functionptr) asm_builtin_aastore,                "aastore"},
-       {(functionptr) builtin_new,                                "new"},
-       {(functionptr) builtin_newarray,       "newarray"},
-       {(functionptr) builtin_anewarray,          "anewarray"},
-#if defined(__I386__)
-       /*
-        * have 2 parameters (needs stack manipulation)
-        */
-       {(functionptr) asm_builtin_newarray,       "newarray"},
-#endif
-       {(functionptr) builtin_newarray_boolean,   "newarray_boolean"},
-       {(functionptr) builtin_newarray_char,      "newarray_char"},
-       {(functionptr) builtin_newarray_float,     "newarray_float"},
-       {(functionptr) builtin_newarray_double,    "newarray_double"},
-       {(functionptr) builtin_newarray_byte,      "newarray_byte"},
-       {(functionptr) builtin_newarray_short,     "newarray_short"},
-       {(functionptr) builtin_newarray_int,       "newarray_int"},
-       {(functionptr) builtin_newarray_long,      "newarray_long"},
-       {(functionptr) builtin_displaymethodstart, "displaymethodstart"},
-       {(functionptr) builtin_displaymethodstop,  "displaymethodstop"},
-       {(functionptr) builtin_monitorenter,       "monitorenter"},
-       {(functionptr) asm_builtin_monitorenter,   "monitorenter"},
-       {(functionptr) builtin_monitorexit,                "monitorexit"},
-       {(functionptr) asm_builtin_monitorexit,    "monitorexit"},
-#if !SUPPORT_DIVISION
-       {(functionptr) builtin_idiv,                       "idiv"},
-       {(functionptr) asm_builtin_idiv,                   "idiv"},
-       {(functionptr) builtin_irem,                       "irem"},
-       {(functionptr) asm_builtin_irem,                   "irem"},
-#endif
-       {(functionptr) builtin_ladd,                       "ladd"},
-       {(functionptr) builtin_lsub,                       "lsub"},
-       {(functionptr) builtin_lmul,                       "lmul"},
-#if !(SUPPORT_DIVISION && SUPPORT_LONG && SUPPORT_LONG_DIV)
-       {(functionptr) builtin_ldiv,                       "ldiv"},
-       {(functionptr) asm_builtin_ldiv,                   "ldiv"},
-       {(functionptr) builtin_lrem,                       "lrem"},
-       {(functionptr) asm_builtin_lrem,                   "lrem"},
-#endif
-       {(functionptr) builtin_lshl,                       "lshl"},
-       {(functionptr) builtin_lshr,                       "lshr"},
-       {(functionptr) builtin_lushr,                      "lushr"},
-       {(functionptr) builtin_land,                       "land"},
-       {(functionptr) builtin_lor,                                "lor"},
-       {(functionptr) builtin_lxor,                       "lxor"},
-       {(functionptr) builtin_lneg,                       "lneg"},
-       {(functionptr) builtin_lcmp,                       "lcmp"},
-       {(functionptr) builtin_fadd,                       "fadd"},
-       {(functionptr) builtin_fsub,                       "fsub"},
-       {(functionptr) builtin_fmul,                       "fmul"},
-       {(functionptr) builtin_fdiv,                       "fdiv"},
-       {(functionptr) builtin_frem,                       "frem"},
-       {(functionptr) builtin_fneg,                       "fneg"},
-       {(functionptr) builtin_fcmpl,                      "fcmpl"},
-       {(functionptr) builtin_fcmpg,                      "fcmpg"},
-       {(functionptr) builtin_dadd,                       "dadd"},
-       {(functionptr) builtin_dsub,                       "dsub"},
-       {(functionptr) builtin_dmul,                       "dmul"},
-       {(functionptr) builtin_ddiv,                       "ddiv"},
-       {(functionptr) builtin_drem,                       "drem"},
-       {(functionptr) builtin_dneg,                       "dneg"},
-       {(functionptr) builtin_dcmpl,                      "dcmpl"},
-       {(functionptr) builtin_dcmpg,                      "dcmpg"},
-       {(functionptr) builtin_i2l,                                "i2l"},
-       {(functionptr) builtin_i2f,                                "i2f"},
-       {(functionptr) builtin_i2d,                                "i2d"},
-       {(functionptr) builtin_l2i,                                "l2i"},
-       {(functionptr) builtin_l2f,                                "l2f"},
-       {(functionptr) builtin_l2d,                                "l2d"},
-       {(functionptr) builtin_f2i,                                "f2i"},
-       {(functionptr) builtin_f2l,                                "f2l"},
-       {(functionptr) builtin_f2d,                                "f2d"},
-       {(functionptr) builtin_d2i,                                "d2i"},
-       {(functionptr) builtin_d2l,                                "d2l"},
-#if defined(__I386__)
-       {(functionptr) asm_builtin_f2i,                    "f2i"},
-       {(functionptr) asm_builtin_f2l,                    "f2l"},
-       {(functionptr) asm_builtin_d2i,                    "d2i"},
-       {(functionptr) asm_builtin_d2l,                    "d2l"},
-#endif
-       {(functionptr) builtin_d2f,                                "d2f"},
-       {(functionptr) NULL,                                       "unknown"}
-};
-#endif
 
+THREADSPECIFIC methodinfo* _threadrootmethod = NULL;
+THREADSPECIFIC void *_thread_nativestackframeinfo=NULL;
 
 /*****************************************************************************
                                                                TYPE CHECKS
@@ -223,7 +129,6 @@ s4 builtin_isanysubclass(classinfo *sub, classinfo *super)
        return res;
 }
 
-/* XXX inline this? */
 s4 builtin_isanysubclass_vftbl(vftbl *sub,vftbl *super)
 {
        int base;
@@ -310,7 +215,6 @@ s4 builtin_checkcast(java_objectheader *obj, classinfo *class)
                        
 ******************************************************************************/
 
-/* XXX inline this? */
 static s4 builtin_descriptorscompatible(arraydescriptor *desc,arraydescriptor *target)
 {
        if (desc==target) return 1;
@@ -318,8 +222,11 @@ static s4 builtin_descriptorscompatible(arraydescriptor *desc,arraydescriptor *t
        if (desc->arraytype != ARRAYTYPE_OBJECT) return 1;
        
        /* {both arrays are arrays of references} */
-       if (desc->dimension == target->dimension)
+       if (desc->dimension == target->dimension) {
+               /* an array which contains elements of interface types is allowed to be casted to Object (JOWENN)*/
+               if ( (desc->elementvftbl->baseval<0) && (target->elementvftbl->baseval==1) ) return 1;
                return builtin_isanysubclass_vftbl(desc->elementvftbl,target->elementvftbl);
+       }
        if (desc->dimension < target->dimension) return 0;
 
        /* {desc has higher dimension than target} */
@@ -388,10 +295,23 @@ java_objectheader *builtin_throw_exception(java_objectheader *local_exceptionptr
                        }
                log_text(logtext);
        }
-       exceptionptr = local_exceptionptr;
+       *exceptionptr = local_exceptionptr;
        return local_exceptionptr;
 }
 
+void builtin_reset_exceptionptr()
+{
+#if defined(USE_THREADS) && defined(NATIVE_THREADS)
+#ifdef HAVE___THREAD
+       _exceptionptr = NULL;
+#else
+       ((nativethread*) pthread_getspecific(tkey_exceptionptr))->_exceptionptr = 0;
+#endif
+#else
+       panic("builtin_reset_exceptionptr should not be used in this configuration");
+#endif
+}
+
 
 /******************* function: builtin_canstore *******************************
 
@@ -512,7 +432,6 @@ s4 builtin_canstore_onedim (java_objectarray *a, java_objectheader *o)
 
 /* This is an optimized version where a is guaranteed to be a
  * one-dimensional array of a class type */
-/* XXX this could be inlined by the code generator */
 s4 builtin_canstore_onedim_class(java_objectarray *a, java_objectheader *o)
 {
        vftbl *elementvftbl;
@@ -567,8 +486,21 @@ s4 builtin_canstore_onedim_class(java_objectarray *a, java_objectheader *o)
 java_objectheader *builtin_new(classinfo *c)
 {
        java_objectheader *o;
-
-       class_init(c);
+/*DEBUGING - NOT THREAD SAFE*/
+/*     static long depth=0;
+       depth++;
+       printf("Entering builtin_new:depth(%ld)",depth);*/
+
+       if (!c->initialized) {
+               if (initverbose) {
+                       char logtext[MAXLOGTEXT];
+                       sprintf(logtext, "Initialize class ");
+                       utf_sprint(logtext + strlen(logtext), c->name);
+                       sprintf(logtext + strlen(logtext), " (from builtin_new)");
+                       log_text(logtext);
+               }
+               class_init(c);
+       }
 
 #ifdef SIZE_FROM_CLASSINFO
        c->alignedsize = align_size(c->instancesize);
@@ -576,12 +508,20 @@ java_objectheader *builtin_new(classinfo *c)
 #else
        o = heap_allocate(c->instancesize, true, c->finalizer);
 #endif
-       if (!o) return NULL;
+       if (!o) {
+               /*DEBUGING - NOT THREAD SAFE*/
+               /*printf("Leaving builtin_new: depth(%ld): NULL",depth);
+               depth--;*/
+               return NULL;
+       }
        
        memset(o, 0, c->instancesize);
 
        o->vftbl = c->vftbl;
 
+       /*DEBUGING - NOT THREAD SAFE*/
+       /* printf("Leaving builtin_new: depth(%ld): object",depth);
+       depth--;*/
        return o;
 }
 
@@ -605,7 +545,7 @@ java_arrayheader *builtin_newarray(s4 size, vftbl *arrayvftbl)
        s4 actualsize;
 
        if (size<0) {
-               exceptionptr=native_new_and_init(loader_load(utf_new_char("java/lang/NegativeArraySizeException")));
+               *exceptionptr=native_new_and_init(loader_load(utf_new_char("java/lang/NegativeArraySizeException")));
                return NULL;
        }
 #ifdef SIZE_FROM_CLASSINFO
@@ -615,7 +555,7 @@ java_arrayheader *builtin_newarray(s4 size, vftbl *arrayvftbl)
 #endif
 
        if (((u4)actualsize)<((u4)size)) { /* overflow */
-               exceptionptr = native_new_and_init(loader_load(utf_new_char("java/lang/OutOfMemoryError")));
+               *exceptionptr = native_new_and_init(loader_load(utf_new_char("java/lang/OutOfMemoryError")));
                return NULL;
        }
        a = heap_allocate(actualsize,
@@ -652,6 +592,12 @@ java_arrayheader *builtin_newarray(s4 size, vftbl *arrayvftbl)
 
 java_objectarray *builtin_anewarray(s4 size, classinfo *component)
 {
+/*
+       printf("builtin_anewarray: classvftbl: %d\n",component->classvftbl);
+       printf("builtin_anewarray: baseval: %d\n",component->vftbl->baseval);
+       utf_display(component->vftbl->class->name);
+       printf("\nbuiltin_anewarray: linked: %d\n",component->linked);
+       utf_display(component->super->name);*/
        return (java_objectarray*) builtin_newarray(size, class_array_of(component)->vftbl);
 }
 
@@ -801,8 +747,10 @@ java_arrayheader *builtin_nmultianewarray (int n, vftbl *arrayvftbl, long *dims)
 
        /* get the vftbl of the components to create */
        componentvftbl = arrayvftbl->arraydesc->componentvftbl;
-       if (!componentvftbl) /* XXX the verifier could check this */
-               panic ("multianewarray with too many dimensions");
+
+       /* The verifier guarantees this. */
+       /* if (!componentvftbl) */
+       /*      panic ("multianewarray with too many dimensions"); */
 
        /* create the component arrays */
        for (i = 0; i < size; i++) {
@@ -824,21 +772,27 @@ java_arrayheader *builtin_nmultianewarray (int n, vftbl *arrayvftbl, long *dims)
        
 *****************************************************************************/
 
-
 u4 methodindent = 0;
 
-java_objectheader *builtin_trace_exception(java_objectheader *exceptionptr,
+java_objectheader *builtin_trace_exception(java_objectheader *_exceptionptr,
                                                                                   methodinfo *method, int *pos, 
+                                                                                  int line,
                                                                                   int noindent)
 {
-       if (!noindent)
-               methodindent--;
-       if (verbose || runverbose) {
-               printf("Exception ");
-               if (exceptionptr) {
-                       utf_display (exceptionptr->vftbl->class->name);
-               }
-               else {
+       if (!noindent) {
+               if (methodindent)
+                       methodindent--;
+               else
+                       log_text("WARNING: unmatched methodindent--");
+       }
+       if (verbose || runverbose || verboseexception) {
+               if (_exceptionptr) {
+                       printf("Exception ");
+                       utf_display(_exceptionptr->vftbl->class->name);
+
+               } else {
+                       printf("Some Throwable");
+/*
                        printf("Error: <Nullpointer instead of exception>");
                        if (!proto_java_lang_ClassCastException) printf("%s","proto_java_lang_ClassCastException==0");
                        if (!proto_java_lang_NullPointerException) printf("%s","proto_java_lang_NullPointerException==0");
@@ -850,24 +804,36 @@ java_objectheader *builtin_trace_exception(java_objectheader *exceptionptr,
                        if (!proto_java_lang_ArrayStoreException) printf("%s","proto_java_lang_ArrayStoreException==0");
                        if (!proto_java_lang_ThreadDeath) printf("%s","proto_java_lang_ThreadDeath==0");
                        if (!proto_java_lang_ThreadDeath) printf("%s","proto_java_lang_ThreadDeath==0");
-
+                       */
                }
                printf(" thrown in ");
+
                if (method) {
-                       utf_display (method->class->name);
+                       utf_display_classname(method->class->name);
                        printf(".");
-                       utf_display (method->name);
+                       utf_display(method->name);
                        if (method->flags & ACC_SYNCHRONIZED)
-                               printf("(SYNC)");
+                               printf("(SYNC");
                        else
-                               printf("(NOSYNC)");
-                       printf("(%p) at position %p\n", method->entrypoint, pos);
-               }
-               else
+                               printf("(NOSYNC");
+                       if (method->flags & ACC_NATIVE) {
+                               printf(",NATIVE");
+                               printf(")(%p) at position %p\n", method->entrypoint, pos);
+                       } else {
+                               printf(")(%p) at position %p (",method->entrypoint,pos);
+                               if (method->class->sourcefile==NULL)
+                                       printf("<NO CLASSFILE INFORMATION>");
+                               else
+                                       utf_display(method->class->sourcefile);
+                               printf(":%d)\n",line);
+                       }
+
+               } else
                        printf("call_java_method\n");
                fflush (stdout);
        }
-       return exceptionptr;
+
+       return _exceptionptr;
 }
 
 
@@ -882,18 +848,33 @@ void builtin_trace_args(s8 a0, s8 a1, s8 a2, s8 a3, s8 a4, s8 a5,
        char logtext[MAXLOGTEXT];
        for (i = 0; i < methodindent; i++)
                logtext[i] = '\t';
+
        sprintf(logtext + methodindent, "called: ");
        utf_sprint(logtext + strlen(logtext), method->class->name);
        sprintf(logtext + strlen(logtext), ".");
        utf_sprint(logtext + strlen(logtext), method->name);
        utf_sprint(logtext + strlen(logtext), method->descriptor);
+
+       if ( method->flags & ACC_PUBLIC )       sprintf (logtext + strlen(logtext)," PUBLIC");
+       if ( method->flags & ACC_PRIVATE )      sprintf (logtext + strlen(logtext)," PRIVATE");
+       if ( method->flags & ACC_PROTECTED )    sprintf (logtext + strlen(logtext)," PROTECTED");
+       if ( method->flags & ACC_STATIC )       sprintf (logtext + strlen(logtext)," STATIC");
+       if ( method->flags & ACC_FINAL )        sprintf (logtext + strlen(logtext)," FINAL");
+       if ( method->flags & ACC_SYNCHRONIZED ) sprintf (logtext + strlen(logtext)," SYNCHRONIZED");
+       if ( method->flags & ACC_VOLATILE )     sprintf (logtext + strlen(logtext)," VOLATILE");
+       if ( method->flags & ACC_TRANSIENT )    sprintf (logtext + strlen(logtext)," TRANSIENT");
+       if ( method->flags & ACC_NATIVE )       sprintf (logtext + strlen(logtext)," NATIVE");
+       if ( method->flags & ACC_INTERFACE )    sprintf (logtext + strlen(logtext)," INTERFACE");
+       if ( method->flags & ACC_ABSTRACT )     sprintf (logtext + strlen(logtext)," ABSTRACT");
+       
+
        sprintf(logtext + strlen(logtext), "(");
 
        switch (method->paramcount) {
        case 0:
                break;
 
-#if defined(__I386__)
+#if defined(__I386__) || defined(__POWERPC__)
        case 1:
                sprintf(logtext+strlen(logtext), "%llx", a0);
                break;
@@ -993,7 +974,8 @@ void builtin_trace_args(s8 a0, s8 a1, s8 a2, s8 a3, s8 a4, s8 a5,
 #endif
 #endif
        }
-       sprintf (logtext+strlen(logtext), ")");
+
+       sprintf(logtext + strlen(logtext), ")");
        log_text(logtext);
 
        methodindent++;
@@ -1010,6 +992,19 @@ void builtin_displaymethodstart(methodinfo *method)
        sprintf(logtext + strlen(logtext), ".");
        utf_sprint(logtext + strlen(logtext), method->name);
        utf_sprint(logtext + strlen(logtext), method->descriptor);
+
+       if ( method->flags & ACC_PUBLIC )       sprintf (logtext + strlen(logtext)," PUBLIC");
+       if ( method->flags & ACC_PRIVATE )      sprintf (logtext + strlen(logtext)," PRIVATE");
+       if ( method->flags & ACC_PROTECTED )    sprintf (logtext + strlen(logtext)," PROTECTED");
+       if ( method->flags & ACC_STATIC )       sprintf (logtext + strlen(logtext)," STATIC");
+       if ( method->flags & ACC_FINAL )        sprintf (logtext + strlen(logtext)," FINAL");
+       if ( method->flags & ACC_SYNCHRONIZED ) sprintf (logtext + strlen(logtext)," SYNCHRONIZED");
+       if ( method->flags & ACC_VOLATILE )     sprintf (logtext + strlen(logtext)," VOLATILE");
+       if ( method->flags & ACC_TRANSIENT )    sprintf (logtext + strlen(logtext)," TRANSIENT");
+       if ( method->flags & ACC_NATIVE )       sprintf (logtext + strlen(logtext)," NATIVE");
+       if ( method->flags & ACC_INTERFACE )    sprintf (logtext + strlen(logtext)," INTERFACE");
+       if ( method->flags & ACC_ABSTRACT )     sprintf (logtext + strlen(logtext)," ABSTRACT");
+
        log_text(logtext);
        methodindent++;
 }
@@ -1021,7 +1016,11 @@ void builtin_displaymethodstop(methodinfo *method, s8 l, double d, float f)
        char logtext[MAXLOGTEXT];
        for (i = 0; i < methodindent; i++)
                logtext[i] = '\t';
-       methodindent--;
+       if (methodindent)
+               methodindent--;
+       else
+               log_text("WARNING: unmatched methodindent--");
+
        sprintf(logtext + methodindent, "finished: ");
        utf_sprint(logtext + strlen(logtext), method->class->name);
        sprintf(logtext + strlen(logtext), ".");
@@ -1032,23 +1031,27 @@ void builtin_displaymethodstop(methodinfo *method, s8 l, double d, float f)
        case TYPE_INT:
                sprintf(logtext + strlen(logtext), "->%d", (s4) l);
                break;
+
        case TYPE_LONG:
-#if defined(__I386__)
+#if defined(__I386__) || defined(__POWERPC__)
                sprintf(logtext + strlen(logtext), "->%lld", (s8) l);
 #else
                sprintf(logtext + strlen(logtext), "->%ld", (s8) l);
 #endif
                break;
+
        case TYPE_ADDRESS:
-#if defined(__I386__)
+#if defined(__I386__) || defined(__POWERPC__)
                sprintf(logtext + strlen(logtext), "->%p", (u1*) ((s4) l));
 #else
                sprintf(logtext + strlen(logtext), "->%p", (u1*) l);
 #endif
                break;
+
        case TYPE_FLOAT:
                sprintf(logtext + strlen(logtext), "->%g", f);
                break;
+
        case TYPE_DOUBLE:
                sprintf(logtext + strlen(logtext), "->%g", d);
                break;
@@ -1081,7 +1084,7 @@ void builtin_displaymethodexception(methodinfo *method)
  */
 void internal_lock_mutex_for_object(java_objectheader *object)
 {
-#ifdef USE_THREADS
+#if defined(USE_THREADS) && !defined(NATIVE_THREADS)
        mutexHashEntry *entry;
        int hashValue;
 
@@ -1131,7 +1134,7 @@ void internal_lock_mutex_for_object(java_objectheader *object)
  */
 void internal_unlock_mutex_for_object (java_objectheader *object)
 {
-#ifdef USE_THREADS
+#if defined(USE_THREADS) && !defined(NATIVE_THREADS)
        int hashValue;
        mutexHashEntry *entry;
 
@@ -1163,9 +1166,11 @@ void internal_unlock_mutex_for_object (java_objectheader *object)
 
 void builtin_monitorenter(java_objectheader *o)
 {
-#ifdef USE_THREADS
+#if defined(USE_THREADS) && !defined(NATIVE_THREADS)
        int hashValue;
 
+       /*log_text("Monitor enter");*/
+
        assert(blockInts == 0);
 
        ++blockInts;
@@ -1186,9 +1191,12 @@ void builtin_monitorenter(java_objectheader *o)
 
 void builtin_monitorexit (java_objectheader *o)
 {
-#ifdef USE_THREADS
+
+#if defined(USE_THREADS) && !defined(NATIVE_THREADS)
        int hashValue;
 
+       /* log_text("Monitor leave"); */
+
        assert(blockInts == 0);
 
        ++blockInts;
@@ -1806,6 +1814,45 @@ java_arrayheader *builtin_clone_array(void *env, java_arrayheader *o)
        return (java_arrayheader *) Java_java_lang_VMObject_clone(0, 0, (java_lang_Cloneable *) o);
 }
 
+s4 builtin_dummy()
+{
+       panic("Internal error: builtin_dummy called (native function is missing)");
+       return 0; /* for the compiler */
+}
+
+
+inline methodinfo *builtin_asm_get_threadrootmethod() {
+        return *threadrootmethod;
+}
+
+
+inline void* 
+builtin_asm_get_stackframeinfo(){
+/*log_text("builtin_asm_get_stackframeinfo()");*/
+#if defined(USE_THREADS) && defined(NATIVE_THREADS)
+#ifdef HAVE___THREAD
+        return &_thread_nativestackframeinfo; /*support for __thread attribute*/
+#else
+    return &((nativethread*) pthread_getspecific(tkey_stackframeinfo))->_stackframeinfo /*copied from exception handling, is that really */
+        /*old pthread*/
+#endif
+#else
+#warning FIXME FOR OLD THREAD IMPL (jowenn)
+        return &_thread_nativestackframeinfo; /* no threading, at least no native*/
+#endif
+}
+
+stacktraceelement *builtin_stacktrace_copy(stacktraceelement **el,stacktraceelement *begin, stacktraceelement *end) {
+/*     stacktraceelement *el;*/
+       size_t s;
+       s=(end-begin);
+       /*printf ("begin: %p, end: %p, diff: %ld, size :%ld\n",begin,end,s,s*sizeof(stacktraceelement));*/
+       *el=GCNEW(stacktraceelement,s+1);
+       memcpy(*el,begin,(end-begin)*sizeof(stacktraceelement));
+       (*el)[s].method=0;
+       (*el)[s].linenumber=0;
+       return *el;
+}
 
 /*
  * These are local overrides for various environment variables in Emacs.