Fix #10976 false negative: autoVariables [inconclusive] (regression) (danmar#5044)

* Fix #10976 false negative: autoVariables [inconclusive] (regression)

* Use link()

* Use linkAt()

* Skip over [][]

Author: chrchr-github

lib/checkautovariables.cpp

@@ -309,8 +309,12 @@ bool CheckAutoVariables::checkAutoVariableAssignment(const Token *expr, bool inc
         }
         if (Token::simpleMatch(tok, "=")) {
             const Token *lhs = tok;
-            while (Token::Match(lhs->previous(), "%name%|.|*"))
-                lhs = lhs->previous();
+            while (Token::Match(lhs->previous(), "%name%|.|*|]")) {
+                if (lhs->linkAt(-1))
+                    lhs = lhs->linkAt(-1);
+                else
+                    lhs = lhs->previous();
+            }
             const Token *e = expr;
             while (e->str() != "=" && lhs->str() == e->str()) {
                 e = e->next();

test/testautovariables.cpp

@@ -617,6 +617,18 @@ class TestAutoVariables : public TestFixture {
               "    pcb->root0 = 0;\n"  // <- conditional reassign => error
               "}");
         ASSERT_EQUALS("[test.cpp:3]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
+
+        check("struct S { int *p; };\n"
+              "void g(struct S* s) {\n"
+              "    int a[10];\n"
+              "    s->p = a;\n"
+              "    a[0] = 0;\n"
+              "}\n"
+              "void f() {\n"
+              "    struct S s;\n"
+              "    g(&s);\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:4]: (error, inconclusive) Address of local auto-variable assigned to a function parameter.\n", errout.str());
     }
 
     void testinvaliddealloc() {