diff --git a/compiler/x86/agx86att.pas b/compiler/x86/agx86att.pas
index c9bd2e3fa4..43c04edb5d 100644
--- a/compiler/x86/agx86att.pas
+++ b/compiler/x86/agx86att.pas
@@ -285,11 +285,7 @@ interface
     procedure Tx86InstrWriter.WriteInstruction(hp: tai);
       var
        op       : tasmop;
-{$ifdef x86_64}
-       val      : aint;
-{$endif}
        calljmp  : boolean;
-       need_second_mov : boolean;
        i        : integer;
        sreg     : string;
       begin
@@ -298,11 +294,6 @@ interface
         taicpu(hp).SetOperandOrder(op_att);
         op:=taicpu(hp).opcode;
         calljmp:=is_calljmp(op);
-        { constant values in the 32 bit range are sign-extended to
-          64 bits, but this is not what we want.  PM 2010-09-02
-          the fix consists of simply setting only the 4-byte register
-          as the upper 4-bytes will be zeroed at the same time. }
-        need_second_mov:=false;
 
         // BUGFIX GAS-assembler
         // Intel "Intel 64 and IA-32 Architectures Software Developers manual 12/2011
@@ -325,26 +316,6 @@ interface
               taicpu(hp).oper[0]^.reg := gas_regnum_search('%x' + copy(sreg, 3, length(sreg) - 2));
           end;
         end;
-{$ifdef x86_64}
-        if (op=A_MOV) and (taicpu(hp).opsize=S_Q) and
-           (taicpu(hp).oper[0]^.typ = top_const) then
-           begin
-             val := taicpu(hp).oper[0]^.val;
-             if (val > int64($7fffffff)) and (val < int64($100000000)) then
-               begin
-                 owner.AsmWrite(target_asm.comment);
-                 owner.AsmWritePChar('Fix for Win64-GAS bug');
-                 owner.AsmLn;
-                 taicpu(hp).opsize:=S_L;
-                 if taicpu(hp).oper[1]^.typ = top_reg then
-                   setsubreg(taicpu(hp).oper[1]^.reg,R_SUBD)
-                 else if taicpu(hp).oper[1]^.typ = top_ref then
-                   need_second_mov:=true
-                 else
-                   internalerror(20100902);
-               end;
-           end;
-{$endif x86_64}
         { see fNoInterUnitMovQ declaration comment }
         if fNoInterUnitMovQ then
           begin
@@ -447,12 +418,6 @@ interface
              end;
           end;
         owner.AsmLn;
-        if need_second_mov then
-          begin
-            taicpu(hp).oper[0]^.val:=0;
-            inc(taicpu(hp).oper[1]^.ref^.offset,4);
-            WriteInstruction(hp);
-          end;
       end;