--- a/Object.st	Fri May 16 17:04:58 1997 +0200
+++ b/Object.st	Tue May 20 15:54:52 1997 +0200
@@ -1759,90 +1759,65 @@
     int flags;
 
     sz = __qSize(self);
-
-    __PROTECT__(self);
-    __qNew(theCopy, sz);
-    __UNPROTECT__(slf);
-    if (theCopy) {
-	spc = __qSpace(theCopy);
-
-	theCopy->o_class = cls = __qClass(slf); __STORE_SPC(theCopy, cls, spc);
-
-	sz = sz - OHDR_SIZE;
-	if (sz) {
-	    char *src, *dst;
-
-	    src = (char *)(__InstPtr(slf)->i_instvars);
-	    dst = (char *)(__InstPtr(theCopy)->i_instvars);
+    cls = __qClass(self);
+    flags = __intVal(__ClassInstPtr(cls)->c_flags);
+
+    /*
+     * bail out for special objects ..
+     */
+    if (((flags & ~ARRAYMASK) == 0)
+     && ((flags & ARRAYMASK) != WKPOINTERARRAY)) {
+	__PROTECT2__(self, cls);
+	__qNew(theCopy, sz);
+	__UNPROTECT2__(cls, slf);
+	if (theCopy) {
+	    spc = __qSpace(theCopy);
+
+	    theCopy->o_class = cls; __STORE_SPC(theCopy, cls, spc);
+
+	    sz = sz - OHDR_SIZE;
+	    if (sz) {
+		char *src, *dst;
+
+		src = (char *)(__InstPtr(slf)->i_instvars);
+		dst = (char *)(__InstPtr(theCopy)->i_instvars);
 #ifdef bcopy4
-	    {
-                /* care for odd-number of longs */
-                int nW = sz >> 2;
-
-                if (sz & 3) {
-		    nW++;
+		{
+		    /* care for odd-number of longs */
+		    int nW = sz >> 2;
+
+		    if (sz & 3) {
+			nW++;
+		    }
+
+		    bcopy4(src, dst, nW);
 		}
-
-                bcopy4(src, dst, nW);
-            }
 #else
-	    bcopy(src, dst, sz);
+		bcopy(src, dst, sz);
 #endif
 
-	    flags = __intVal(__ClassInstPtr(cls)->c_flags) & ARRAYMASK;
-	    if ((flags == POINTERARRAY) || (flags == WKPOINTERARRAY)) {
-	        ninsts = __BYTES2OBJS__(sz);
-	    } else {
-	        ninsts = __intVal(__ClassInstPtr(cls)->c_ninstvars);
+		flags &= ARRAYMASK;
+		if ((flags == POINTERARRAY) || (flags == WKPOINTERARRAY)) {
+		    ninsts = __BYTES2OBJS__(sz);
+		} else {
+		    ninsts = __intVal(__ClassInstPtr(cls)->c_ninstvars);
+		}
+		if (ninsts) {
+		    do {
+			OBJ el;
+
+			el = __InstPtr(theCopy)->i_instvars[ninsts-1];
+			__STORE_SPC(theCopy, el, spc);
+		    } while (--ninsts);
+		}
 	    }
-	    if (ninsts) {
-	        do {
-		    OBJ el;
-
-		    el = __InstPtr(theCopy)->i_instvars[ninsts-1];
-		    __STORE_SPC(theCopy, el, spc);
-	        } while (--ninsts);
-	    }
+	    RETURN (theCopy);
 	}
-	RETURN (theCopy);
     }
 %}.
-    "
-     memory allocation failed.
-     When we arrive here, there was no memory, even after
-     a garbage collect. 
-     This means, that the VM wanted to get some more memory from the 
-     Operatingsystem, which was not kind enough to give it.
-     Bad luck - you should increase the swap space on your machine.
-    "
-    ^ ObjectMemory allocationFailureSignal raise.
-
-"/
-"/ the above is equivalent to the code below (but much faster) ...
-"/
-"/    |myClass aCopy 
-"/     sz "{ Class: SmallInteger }" |
-"/
-"/    myClass := self class.
-"/    myClass isVariable ifTrue:[
-"/        sz := self basicSize.
-"/        aCopy := myClass basicNew:sz.
-"/
-"/        "copy the indexed variables"
-"/        1 to:sz do:[:i | 
-"/            aCopy basicAt:i put:(self basicAt:i) 
-"/        ]
-"/    ] ifFalse:[
-"/        aCopy := myClass basicNew
-"/    ].
-"/
-"/    "copy the instance variables"
-"/    sz := myClass instSize.
-"/    1 to:sz do:[:i | 
-"/        aCopy instVarAt:i put:(self instVarAt:i) 
-"/    ].
-"/
-"/    ^ aCopy
+    "/ fallBack for special objects & memoryAllocation failure case
+
+    ^ self slowShallowCopy
 
 !
 
@@ -1895,6 +1870,36 @@
      a at:3 put:a.
      a simpleDeepCopy
     "
+!
+
+slowShallowCopy
+    "return a copy of the object with shared subobjects (a shallow copy)
+     i.e. the copy shares referenced instvars with its original.
+     This method is only invoked as a fallback from #shallowCopy."
+
+    |myClass aCopy 
+     sz "{ Class: SmallInteger }" |
+
+    myClass := self class.
+    myClass isVariable ifTrue:[
+	sz := self basicSize.
+	aCopy := myClass basicNew:sz.
+
+	"copy the indexed variables"
+	1 to:sz do:[:i | 
+	    aCopy basicAt:i put:(self basicAt:i) 
+	]
+    ] ifFalse:[
+	aCopy := myClass basicNew
+    ].
+
+    "copy the instance variables"
+    sz := myClass instSize.
+    1 to:sz do:[:i | 
+	aCopy instVarAt:i put:(self instVarAt:i) 
+    ].
+
+    ^ aCopy
 ! !
 
 !Object methodsFor:'debugging'!
@@ -5979,6 +5984,6 @@
 !Object class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/Object.st,v 1.191 1997-05-14 14:44:23 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/Object.st,v 1.192 1997-05-20 13:54:52 cg Exp $'
 ! !
 Object initialize!