Fix FN uninitVar with std::array (#3707)

Author: chrchr-github

lib/checkuninitvar.cpp

@@ -137,8 +137,11 @@ void CheckUninitVar::checkScope(const Scope* scope, const std::set<std::string>
             if (tok->isStandardType() || tok->isEnumType())
                 stdtype = true;
         }
-        if (var.isArray() && !stdtype)
-            continue;
+        if (var.isArray() && !stdtype) { // std::array
+            if (!(var.isStlType() && Token::simpleMatch(var.typeStartToken(), "std :: array") && var.valueType() &&
+                  var.valueType()->containerTypeToken && var.valueType()->containerTypeToken->isStandardType()))
+                continue;
+        }
 
         while (tok && tok->str() != ";")
             tok = tok->next();

test/testuninitvar.cpp

@@ -1773,6 +1773,18 @@ class TestUninitVar : public TestFixture {
                        "  fred[1].x = 0;\n"
                        "}", "test.c");
         ASSERT_EQUALS("", errout.str());
+
+        checkUninitVar("char f() {\n"
+                       "    std::array<char, 1> a;\n"
+                       "    return a[0];\n"
+                       "}\n");
+        ASSERT_EQUALS("[test.cpp:3]: (error) Uninitialized variable: a\n", errout.str());
+
+        checkUninitVar("std::string f() {\n"
+                       "    std::array<std::string, 1> a;\n"
+                       "    return a[0];\n"
+                       "}\n");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void uninitvar_pointertoarray() {