Fix 10532, 14835, 20522 by adding test cases

compiler/src/dmd/blockexit.d

@@ -155,7 +155,7 @@ int blockExit(Statement s, FuncDeclaration func, ErrorSink eSink)
                     {
                         import dmd.errorsink : DiagnosticFlag;
                         version (none) // this warning is completely useless due to insane false positive rate in real life template code
-                        if (blockExit(s, func, mustNotThrow) != BE.halt && s.hasCode() &&
+                        if (blockExit(s, func, eSink) != BE.halt && s.hasCode() &&
                             s.loc != Loc.initial) // don't emit warning for generated code
                             global.errorSink.warning(DiagnosticFlag.unreachable, s.loc, "statement is not reachable");
                     }

compiler/test/compilable/warn12809.d

@@ -71,3 +71,27 @@ void test3()
     finally foo();
     int x = 1;
 }
+
+// https://issues.dlang.org/show_bug.cgi?id=14835
+bool isEven(int i)()
+{
+    static if (i % 2)
+        return true;
+    return false;
+}
+
+enum x = isEven!0;
+
+// https://issues.dlang.org/show_bug.cgi?id=10532
+alias Seq(T...) = T;
+void f()
+{
+    foreach (e; Seq!(10, 20))
+    {
+        if (e == 10)
+            continue;
+
+        // lots of code follows..
+        auto x = 1;
+    }
+}

compiler/test/fail_compilation/test20522.d

@@ -0,0 +1,23 @@
+/*
+REQUIRED_ARGS: -w
+TEST_OUTPUT:
+---
+fail_compilation/test20522.d(19): Error: undefined identifier `non_existent`
+---
+*/
+
+// https://issues.dlang.org/show_bug.cgi?id=20522
+struct File
+{
+    ~this() {}
+}
+
+void main()
+{
+	{
+		auto test = File(); // <- Essential
+		non_existent;
+	}
+	// Warning: statement is not reachable
+	string[] is_this_unreachable_question_mark;
+}