Added hasUnalignedFields helper to check if a type has unaligned fields - as per request from fvbommel. Result is cached in TypeStruct.

dmd/mtype.c

@@ -4278,6 +4278,9 @@ TypeStruct::TypeStruct(StructDeclaration *sym)
 	: Type(Tstruct, NULL)
 {
     this->sym = sym;
+
+    // LDC
+    this->unaligned = 0;
 }
 
 char *TypeStruct::toChars()

dmd/mtype.h

@@ -542,6 +542,11 @@ struct TypeStruct : Type
     int hasPointers();
 
     type *toCtype();
+
+    // LDC
+    // cache the hasUnalignedFields check
+    // 0 = not checked, 1 = aligned, 2 = unaligned
+    int unaligned;
 };
 
 struct TypeEnum : Type