Fix 12606 and 12287: FP uninitvar when passing address to function (#6261)

Author: pfultz2

lib/astutils.cpp

@@ -3365,6 +3365,8 @@ ExprUsage getExprUsage(const Token* tok, int indirect, const Settings* settings)
             return ExprUsage::NotUsed;
         if (Token::simpleMatch(parent, ":") && Token::simpleMatch(parent->astParent(), "?"))
             return getExprUsage(parent->astParent(), indirect, settings);
+        if (isUsedAsBool(tok, settings))
+            return ExprUsage::NotUsed;
     }
     if (indirect == 0) {
         if (Token::Match(parent, "%cop%|%assign%|++|--") && parent->str() != "=" &&

lib/checkuninitvar.cpp

@@ -1652,14 +1652,11 @@ void CheckUninitVar::valueFlowUninit()
                     continue;
                 if (!v->subexpressions.empty() && usage == ExprUsage::PassedByReference)
                     continue;
-                bool inconclusive = false;
-                if (usage == ExprUsage::Used && v->tokvalue && tok->variable() && tok->variable()->isArgument() &&
-                    (!isVariableChangedByFunctionCall(v->tokvalue, v->indirect, mSettings, &inconclusive) || inconclusive))
-                    continue;
                 if (usage != ExprUsage::Used) {
                     if (!(Token::Match(tok->astParent(), ". %name% (|[") && uninitderef) &&
                         isVariableChanged(tok, v->indirect, mSettings))
                         continue;
+                    bool inconclusive = false;
                     if (isVariableChangedByFunctionCall(tok, v->indirect, mSettings, &inconclusive) || inconclusive)
                         continue;
                 }

test/testuninitvar.cpp

@@ -6143,7 +6143,7 @@ class TestUninitVar : public TestFixture {
                         "    increment(n);\n"
                         "    return n;\n"
                         "}\n");
-        ASSERT_EQUALS("", errout_str());
+        ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:1]: (warning) Uninitialized variable: i\n", errout_str());
 
         // #11412
         valueFlowUninit("void f(int n) {\n"
@@ -6467,6 +6467,14 @@ class TestUninitVar : public TestFixture {
                         "  if ((success == 1) && (myst.a != 0)) {}\n"
                         "}\n");
         ASSERT_EQUALS("", errout_str());
+
+        // #12606
+        valueFlowUninit("void f(int& r) { if (r) {} }\n"
+                        "void g() {\n"
+                        "    int i;\n"
+                        "    f(i);\n"
+                        "}\n");
+        ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:1]: (warning) Uninitialized variable: r\n", errout_str());
     }
 
     void valueFlowUninitBreak() { // Do not show duplicate warnings about the same uninitialized value