Fix #10259 debug: SymbolDatabase couldn't resolve all user defined types (#4879)

Author: chrchr-github

lib/symboldatabase.cpp

@@ -891,6 +891,8 @@ void SymbolDatabase::createSymbolDatabaseNeedInitialization()
             for (Scope& scope : scopeList) {
                 if (!scope.isClassOrStructOrUnion())
                     continue;
+                if (scope.classDef && Token::simpleMatch(scope.classDef->previous(), ">")) // skip uninstantiated template
+                    continue;
 
                 if (!scope.definedType) {
                     mBlankTypes.emplace_back();

test/testsymboldatabase.cpp

@@ -267,6 +267,7 @@ class TestSymbolDatabase : public TestFixture {
         TEST_CASE(namespaces2);
         TEST_CASE(namespaces3);  // #3854 - unknown macro
         TEST_CASE(namespaces4);
+        TEST_CASE(needInitialization);
 
         TEST_CASE(tryCatch1);
 
@@ -2790,6 +2791,20 @@ class TestSymbolDatabase : public TestFixture {
         ASSERT_EQUALS(2U, fredAType->classDef->linenr());
     }
 
+    void needInitialization() { // #10259
+        const auto oldSettings = settings1;
+        settings1.debugwarnings = true;
+
+        GET_SYMBOL_DB("template <typename T>\n"
+                      "struct A {\n"
+                      "    using type = T;\n"
+                      "    type t_;\n"
+                      "};\n");
+        ASSERT_EQUALS("", errout.str());
+
+        settings1 = oldSettings;
+    }
+
     void tryCatch1() {
         const char str[] = "void foo() {\n"
                            "    try { }\n"