Fix potential NPE due to use of an uninitialized child node in LookupAttributeInMRONode

steve-s · steve-s · commit 4f3661c16be9 · 2020-07-15T17:40:59.000+02:00
diff --git a/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/attributes/LookupAttributeInMRONode.java b/graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/attributes/LookupAttributeInMRONode.java
@@ -268,7 +268,7 @@ protected Object lookupConstantMRO(@SuppressWarnings("unused") Object klass,
     @Specialization(replaces = {"lookupConstantMROCached", "lookupConstantMRO"})
     protected Object lookup(Object klass,
                     @Cached("createForceType()") ReadAttributeFromObjectNode readAttrNode) {
-        return lookupSlow(klass, key, getMroNode, readAttrNode, skipPythonClasses);
+        return lookupSlow(klass, key, ensureGetMroNode(), readAttrNode, skipPythonClasses);
     }
 
     protected GetMroStorageNode ensureGetMroNode() {

Original file line number	Diff line number	Diff line change
`@@ -268,7 +268,7 @@ protected Object lookupConstantMRO(@SuppressWarnings("unused") Object klass,`
`268`	`268`	`@Specialization(replaces = {"lookupConstantMROCached", "lookupConstantMRO"})`
`269`	`269`	`protected Object lookup(Object klass,`
`270`	`270`	`@Cached("createForceType()") ReadAttributeFromObjectNode readAttrNode) {`
`271`		`- return lookupSlow(klass, key, getMroNode, readAttrNode, skipPythonClasses);`
	`271`	`+ return lookupSlow(klass, key, ensureGetMroNode(), readAttrNode, skipPythonClasses);`
`272`	`272`	`}`
`273`	`273`
`274`	`274`	`protected GetMroStorageNode ensureGetMroNode() {`