diff --git a/rtl/i8086/i8086.inc b/rtl/i8086/i8086.inc
index 69cf8e6ef2..f2de1c27b8 100644
--- a/rtl/i8086/i8086.inc
+++ b/rtl/i8086/i8086.inc
@@ -107,3 +107,56 @@ begin
   runerror(304);
 end;
 
+{****************************************************************************
+                                  FPU
+****************************************************************************}
+
+const
+  { Internal constants for use in system unit }
+  FPU_Invalid = 1;
+  FPU_Denormal = 2;
+  FPU_DivisionByZero = 4;
+  FPU_Overflow = 8;
+  FPU_Underflow = $10;
+  FPU_StackUnderflow = $20;
+  FPU_StackOverflow = $40;
+  FPU_ExceptionMask = $ff;
+
+  { use Default8087CW instead
+  fpucw : word = $1300 or FPU_StackUnderflow or FPU_Underflow or FPU_Denormal;
+  }
+
+
+{$define FPC_SYSTEM_HAS_SYSINITFPU}
+Procedure SysInitFPU;
+  var
+    { these locals are so we don't have to hack pic code in the assembler }
+    localmxcsr: dword;
+    localfpucw: word;
+  begin
+    localfpucw:=Default8087CW;
+    asm
+      fninit
+      fldcw   localfpucw
+      fwait
+    end;
+    softfloat_exception_mask:=float_flag_underflow or float_flag_inexact or float_flag_denormal;
+  end;
+
+
+{$define FPC_SYSTEM_HAS_SYSRESETFPU}
+Procedure SysResetFPU;
+  var
+    { these locals are so we don't have to hack pic code in the assembler }
+    localmxcsr: dword;
+    localfpucw: word;
+  begin
+    localfpucw:=Default8087CW;
+    asm
+      fninit
+      fwait
+      fldcw   localfpucw
+    end;
+    softfloat_exception_flags:=0;
+  end;
+
diff --git a/rtl/i8086/math.inc b/rtl/i8086/math.inc
index d067c2e164..b60613cc52 100644
--- a/rtl/i8086/math.inc
+++ b/rtl/i8086/math.inc
@@ -15,6 +15,34 @@
  **********************************************************************}
 
 {$asmmode intel}
+
+{****************************************************************************
+                            FPU Control word
+ ****************************************************************************}
+
+    procedure Set8087CW(cw:word);
+      begin
+        { pic-safe ; cw will not be a regvar because it's accessed from }
+        { assembler                                                     }
+        default8087cw:=cw;
+        asm
+          fnclex
+          fldcw cw
+        end;
+      end;
+
+
+    function Get8087CW:word;assembler;
+      asm
+        push bp
+        mov bp, sp
+        push ax
+        fnstcw [bp - 2]
+        pop ax
+        mov sp, bp
+        pop bp
+      end;
+
 {****************************************************************************
                        EXTENDED data type routines
  ****************************************************************************}
diff --git a/rtl/inc/mathh.inc b/rtl/inc/mathh.inc
index 60356d2e6f..7967ef1c10 100644
--- a/rtl/inc/mathh.inc
+++ b/rtl/inc/mathh.inc
@@ -14,14 +14,16 @@
 
    { i386 FPU Controlword }
 
-{$if defined(cpui386) or defined(cpux86_64)}
+{$if defined(cpui8086) or defined(cpui386) or defined(cpux86_64)}
     const
       Default8087CW : word = $1332;
 
     procedure Set8087CW(cw:word);
     function Get8087CW:word;
+  {$ifndef cpui8086}
     procedure SetSSECSR(w : dword);
     function GetSSECSR : dword;
+  {$endif not cpui8086}
 {$endif}
 
 const
diff --git a/rtl/msdos/system.pp b/rtl/msdos/system.pp
index 0e9c06487b..baa6ca2f99 100644
--- a/rtl/msdos/system.pp
+++ b/rtl/msdos/system.pp
@@ -214,6 +214,7 @@ end;
 begin
   StackLength := CheckInitialStkLen(InitialStkLen);
   StackBottom := __stkbottom;
+  SysInitFPU;
   { To be set if this is a GUI or console application }
   IsConsole := TRUE;
   { To be set if this is a library and not a program  }