diff --git a/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/MIExpressions.java b/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/MIExpressions.java
index 931e85728ce..64c4783f289 100644
--- a/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/MIExpressions.java
+++ b/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/MIExpressions.java
@@ -234,6 +234,25 @@ public class MIExpressions extends AbstractDsfService implements IMIExpressions,
 		public void setChildCountLimit(int newLimit) {
 			this.childCountLimit = newLimit;
 		}
+		
+		/**
+		 * @return if this expression is part of the memory space or not.
+		 *         If it not part of the memory space, it won't have an address.
+		 * @since 4.2
+		 */
+		public boolean inMemory() {
+			// Registers and convenience variables which both start with $
+			// are not part of memory.  We care about the top-most parent
+			// as it is the only one that can be a register or convenience var.
+			if (getParent() == null) {
+				if (getRelExpr().startsWith("$")) { //$NON-NLS-1$			
+					return false;
+				}
+				return true;
+			}
+			
+			return getParent().inMemory();
+		}
 	}
 	
     /**
@@ -1066,9 +1085,12 @@ public class MIExpressions extends AbstractDsfService implements IMIExpressions,
         
     	if (dmc instanceof MIExpressionDMC) {
     		MIExpressionDMC miDMC = (MIExpressionDMC) dmc;
-    		if (miDMC.getExpressionInfo().hasDynamicAncestor()) {
+    		if (miDMC.getExpressionInfo().hasDynamicAncestor() ||
+    			!miDMC.getExpressionInfo().inMemory()) {
     			// For children of dynamic varobjs, there is no full expression that gdb
-    			// could evaluate in order to provide address and size. 
+    			// could evaluate in order to provide address and size.
+    			// Also, if an expression is not in memory, such as a register
+    			// or a GDB convenience variable, there is no address to return
 				rm.setData(new InvalidDMAddress());
 				rm.done();
 				return;
diff --git a/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/MIMemory.java b/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/MIMemory.java
index 67cc4f3da5f..be7fa3dc801 100644
--- a/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/MIMemory.java
+++ b/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/MIMemory.java
@@ -518,18 +518,20 @@ public class MIMemory extends AbstractDsfService implements IMemory, ICachingSer
 					protected void handleSuccess() {
 						// Figure out which memory area was modified
 						IExpressionDMAddress expression = getData();
-						final int count = expression.getSize();
 						IAddress expAddress = expression.getAddress();
-						final Addr64 address;
-						if (expAddress instanceof Addr64)
-							address = (Addr64) expAddress;
-						else
-							address = new Addr64(expAddress.getValue());
+						if (expAddress != IExpressions.IExpressionDMLocation.INVALID_ADDRESS) {
+							final int count = expression.getSize();
+							final Addr64 address;
+							if (expAddress instanceof Addr64)
+								address = (Addr64) expAddress;
+							else
+								address = new Addr64(expAddress.getValue());
 
-						final IMemoryDMContext memoryDMC = DMContexts.getAncestorOfType(context, IMemoryDMContext.class);
-						getMemoryCache(memoryDMC).refreshMemory(memoryDMC, address, 0, 1, count, true,
-								new RequestMonitor(getExecutor(), null));
+							final IMemoryDMContext memoryDMC = DMContexts.getAncestorOfType(context, IMemoryDMContext.class);
+							getMemoryCache(memoryDMC).refreshMemory(memoryDMC, address, 0, 1, count, true,
+									new RequestMonitor(getExecutor(), null));
 						}
+					}
 			});
 		}
 	}