diff --git a/basis/cpu/x86/32/bootstrap.factor b/basis/cpu/x86/32/bootstrap.factor
index 3bf5e84cf3..96eef9864d 100755
--- a/basis/cpu/x86/32/bootstrap.factor
+++ b/basis/cpu/x86/32/bootstrap.factor
@@ -104,7 +104,9 @@ IN: bootstrap.x86
 
 :: jit-signal-handler-prolog ( -- frame-size )
     stack-frame-size 8 bootstrap-cells + :> frame-size
-    ESP frame-size bootstrap-cell - SUB ! minus a cell for return address
+    ! minus a cell each for flags and return address
+    ! use LEA so we don't dirty flags
+    ESP ESP frame-size 2 bootstrap-cells - neg [+] LEA
     ESP []                    EAX MOV
     ESP 1 bootstrap-cells [+] ECX MOV
     ESP 2 bootstrap-cells [+] EDX MOV
@@ -112,6 +114,7 @@ IN: bootstrap.x86
     ESP 4 bootstrap-cells [+] EBP MOV
     ESP 5 bootstrap-cells [+] ESI MOV
     ESP 6 bootstrap-cells [+] EDI MOV
+    PUSHF
     ESP frame-size 3 bootstrap-cells - [+] 0 MOV rc-absolute-cell rel-this
     ESP frame-size 2 bootstrap-cells - [+] frame-size MOV
     ! subprimitive definition assumes vm's been loaded
@@ -119,6 +122,7 @@ IN: bootstrap.x86
     frame-size ;
 
 :: jit-signal-handler-epilog ( frame-size -- )
+    POPF
     EAX ESP []                    MOV
     ECX ESP 1 bootstrap-cells [+] MOV
     EDX ESP 2 bootstrap-cells [+] MOV
@@ -126,7 +130,7 @@ IN: bootstrap.x86
     EBP ESP 4 bootstrap-cells [+] MOV
     ESI ESP 5 bootstrap-cells [+] MOV
     EDI ESP 6 bootstrap-cells [+] MOV
-    ESP frame-size bootstrap-cell - ADD ;
+    ESP ESP frame-size 2 bootstrap-cells - [+] LEA ;
 
 [
     EAX ds-reg [] MOV
diff --git a/basis/cpu/x86/64/bootstrap.factor b/basis/cpu/x86/64/bootstrap.factor
index cf46b2c43d..a6919e4560 100755
--- a/basis/cpu/x86/64/bootstrap.factor
+++ b/basis/cpu/x86/64/bootstrap.factor
@@ -96,10 +96,12 @@ IN: bootstrap.x86
 
 :: jit-signal-handler-prolog ( -- frame-size )
     signal-handler-save-regs :> save-regs
-    save-regs length bootstrap-cells 16 align stack-frame-size + :> frame-size
-    RSP frame-size bootstrap-cell - SUB ! minus a cell for return address
-    save-regs
-    [| r i | RSP i bootstrap-cells [+] r MOV ] each-index
+    save-regs length 1 + bootstrap-cells 16 align stack-frame-size + :> frame-size
+    ! minus a cell each for flags, return address
+    ! use LEA so we don't dirty flags
+    RSP RSP frame-size 2 bootstrap-cells - neg [+] LEA
+    save-regs [| r i | RSP i bootstrap-cells [+] r MOV ] each-index
+    PUSHF
     ! Now that the registers are saved, we can make the stack frame
     RAX 0 MOV rc-absolute-cell rel-this
     RSP frame-size 3 bootstrap-cells - [+] RAX MOV
@@ -107,9 +109,10 @@ IN: bootstrap.x86
     frame-size ;
 
 :: jit-signal-handler-epilog ( frame-size -- )
+    POPF
     signal-handler-save-regs
     [| r i | r RSP i bootstrap-cells [+] MOV ] each-index
-    RSP frame-size bootstrap-cell - ADD ;
+    RSP RSP frame-size 2 bootstrap-cells - [+] LEA ;
 
 [
     arg1 ds-reg [] MOV