Issue 5105

DMD doesn't allow member function templates in synchronized class:
--------------------
void main()
{
 auto c = new C;
 c.foo(10); // (4)
}
synchronized shared class C
{
 void foo(T)(T a) {} // (8)
}
--------------------
test.d(8): Error: function test.C.foo!(int).foo synchronized function foo must be a member of a class
test.d(4): Error: template instance test.C.foo!(int) error instantiating
--------------------
Patch against dmd r727:
--------------------
--- src/func.c
+++ src/func.c
@@ -1551,7 +1551,8 @@ void FuncDeclaration::semantic3(Scope *sc)
 if (isSynchronized())
 { /* Wrap the entire function body in a synchronized statement
 */
- ClassDeclaration *cd = parent->isClassDeclaration();
+ AggregateDeclaration *ad = isThis();
+ ClassDeclaration *cd = ad ? ad->isClassDeclaration() : NULL;
 if (cd)
 {
 #if TARGET_WINDOS
--------------------

The patch works for a simplified test case:
void main()
{
 auto c = new C;
 c.foo(10);
}
synchronized class C
{
 void foo(T)(T a) {}
}
Since DMD2.051, the original test case hits bug 5504.

Fixed:
https://github.com/D-Programming-Language/dmd/commit/f25d6e98609259de5714b805f45f16880dd3031b 

test_case_5105.d:
void main()
{
 auto c = new C;
 c.foo(10);
}
synchronized class C
{
 void foo(T)(T a) {}
}
Fails again in DMD 2.065 or before : 
dmd test_case_5105.d 
test_case_5105.d(12): Error: template test_case_5105.C.foo cannot deduce function from argument types !()(int), candidates are:
test_case_5105.d(3): test_case_5105.C.foo(T)(T a)

The test case was invalid, shared and synchronized keywords modifies the type of object when applied on class.
synchronized class synchronized_C
{
	void foo(T)(T a) {}
}
shared class shared_C
{
 void foo(T)(T a) {}
}
synchronized shared class synchronized_shared_C
{
	void foo(T)(T a) {}
}
void main()
{
 auto c1 = new shared synchronized_C;
 c1.foo(10);
 
 auto c2 = new shared shared_C;
 c2.foo(10);
 auto c3 = new shared synchronized_shared_C;
 c3.foo(10);
}