ld64 support for slidable static images -- _mh_execute_header

<rdar://problem/10280094>

--- src/ld/LinkEditClassic.hpp
+++ src/ld/LinkEditClassic.hpp
@@ -356,8 +356,9 @@ void SymbolTableAtom<A>::addGlobal(const ld::Atom* atom, StringPoolAtom* pool)
 				entry.set_n_type(N_EXT | N_SECT | N_PEXT);
 		}
 		else if ( (atom->symbolTableInclusion() == ld::Atom::symbolTableInAndNeverStrip)
-					&& (atom->section().type() == ld::Section::typeMachHeader) ) {
-			// the __mh_execute_header is historical magic and must be an absolute symbol
+					&& (atom->section().type() == ld::Section::typeMachHeader) 
+					&& !_options.positionIndependentExecutable() ) {
+			// the __mh_execute_header is historical magic in non-pie executabls and must be an absolute symbol
 			entry.set_n_type(N_EXT | N_ABS);
 		}
 	}