Merge pull request #3688 from 9rnsr/fix12970

Issue 12970 - Enclosing @System attribute is precedence than postfix @safe

Author: WalterBright

src/func.c

@@ -470,6 +470,8 @@ void FuncDeclaration::semantic(Scope *sc)
         if (tf->isnogc)     sc->stc |= STCnogc;
         if (tf->isproperty) sc->stc |= STCproperty;
         if (tf->purity == PUREfwdref)   sc->stc |= STCpure;
+        if (tf->trust != TRUSTdefault)
+            sc->stc &= ~(STCsafe | STCsystem | STCtrusted);
         if (tf->trust == TRUSTsafe)     sc->stc |= STCsafe;
         if (tf->trust == TRUSTsystem)   sc->stc |= STCsystem;
         if (tf->trust == TRUSTtrusted)  sc->stc |= STCtrusted;

test/compilable/testInference.d

@@ -504,6 +504,37 @@ alias FP12704 = typeof(function() { foo12704(); });
 static assert(is(FP12704 == void function() @system));
 
 /***************************************************/
+// 12970
+
+@system { @safe void f12970a() {} }
+@system { void f12970b() @safe {} }
+static assert(is(typeof(&f12970a) == void function() @safe));
+static assert(is(typeof(&f12970b) == void function() @safe));
+
+@system { @trusted void f12970c() {} }
+@system { void f12970d() @trusted {} }
+static assert(is(typeof(&f12970c) == void function() @trusted));
+static assert(is(typeof(&f12970d) == void function() @trusted));
+
+@safe { @system void f12970e() {} }
+@safe { void f12970f() @system {} }
+static assert(is(typeof(&f12970e) == void function() @system));
+static assert(is(typeof(&f12970f) == void function() @system));
+
+@safe { @trusted void f12970g() {} }
+@safe { void f12970h() @trusted {} }
+static assert(is(typeof(&f12970g) == void function() @trusted));
+static assert(is(typeof(&f12970h) == void function() @trusted));
+
+@trusted { @safe void f12970i() {} }
+@trusted { void f12970j() @safe {} }
+static assert(is(typeof(&f12970i) == void function() @safe));
+static assert(is(typeof(&f12970j) == void function() @safe));
+
+@trusted { @system void f12970k() {} }
+@trusted { void f12970l() @system {} }
+static assert(is(typeof(&f12970k) == void function() @system));
+static assert(is(typeof(&f12970l) == void function() @system));
 
 // Add more tests regarding inferences later.