diff --git a/lib/checkleakautovar.cpp b/lib/checkleakautovar.cpp
index e13cda5bd..7a97acaac 100644
--- a/lib/checkleakautovar.cpp
+++ b/lib/checkleakautovar.cpp
@@ -362,8 +362,20 @@ void CheckLeakAutoVar::checkScope(const Token * const startToken,
                 VarInfo old;
                 old.swap(*varInfo);
 
-                // Conditional allocation in varInfo1
                 std::map<unsigned int, VarInfo::AllocInfo>::const_iterator it;
+
+                for (it = old.alloctype.begin(); it != old.alloctype.end(); ++it) {
+                    const unsigned int varId = it->first;
+                    if (old.conditionalAlloc.find(varId) == old.conditionalAlloc.end())
+                        continue;
+                    if (varInfo1.alloctype.find(varId) == varInfo1.alloctype.end() ||
+                        varInfo2.alloctype.find(varId) == varInfo2.alloctype.end()) {
+                        varInfo1.erase(varId);
+                        varInfo2.erase(varId);
+                    }
+                }
+
+                // Conditional allocation in varInfo1
                 for (it = varInfo1.alloctype.begin(); it != varInfo1.alloctype.end(); ++it) {
                     if (varInfo2.alloctype.find(it->first) == varInfo2.alloctype.end() &&
                         old.alloctype.find(it->first) == old.alloctype.end()) {
diff --git a/test/testleakautovar.cpp b/test/testleakautovar.cpp
index 311d50c19..3b685698c 100644
--- a/test/testleakautovar.cpp
+++ b/test/testleakautovar.cpp
@@ -98,6 +98,7 @@ private:
         TEST_CASE(return2);
         TEST_CASE(return3);
         TEST_CASE(return4);
+        TEST_CASE(return5);
 
         // General tests: variable type, allocation type, etc
         TEST_CASE(test1);
@@ -1043,6 +1044,20 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void return5() { // ticket #6397 - conditional allocation/deallocation and conditional return
+        // avoid false positives
+        check("void f(int *p, int x) {\n"
+              "    if (x != 0) {\n"
+              "        free(p);\n"
+              "    }\n"
+              "    if (x != 0) {\n"
+              "        return;\n"
+              "    }\n"
+              "    *p = 0;\n"
+              "}", true);
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void test1() { // 3809
         check("void f(double*&p) {\n"
               "    p = malloc(0x100);\n"