diff --git a/runtime/Makefile b/runtime/Makefile
index c4414a5c8..906aa571d 100644
--- a/runtime/Makefile
+++ b/runtime/Makefile
@@ -1,6 +1,12 @@
-all:
-	gcc -m32 -c runtime.c
+all: gc_runtime.o runtime.o
+	ar rc runtime.a gc_runtime.o runtime.o 
+
+gc_runtime.o: gc_runtime.s
+	gcc -g -m32 -c gc_runtime.s
+
+runtime.o: runtime.c
+	gcc -g -m32 -c runtime.c
 
 clean:
-	rm -f runtime.o *~
+	rm -f *.a *.o *~
 
diff --git a/runtime/gc_runtime.s b/runtime/gc_runtime.s
new file mode 100644
index 000000000..3df87be0a
--- /dev/null
+++ b/runtime/gc_runtime.s
@@ -0,0 +1,68 @@
+			.data
+printf_format:		.string	"Stack root: %lx\n"
+printf_format2:		.string	"BOT: %lx\n"
+printf_format3:		.string	"TOP: %lx\n"
+printf_format4:		.string	"EAX: %lx\n"
+printf_format5:		.string	"LOL\n"
+__gc_stack_bottom:	.long	0
+__gc_stack_top:	        .long	0
+	
+			.globl L__gc_init
+			.globl __gc_root_scan_stack
+	
+			.text
+L__gc_init:		movl	%esp, __gc_stack_bottom
+			addl	$4, __gc_stack_bottom
+			ret
+
+__gc_root_scan_stack:
+			movl	%esp, __gc_stack_top
+			movl	%esp, %eax
+			jmp next
+
+loop:
+			movl	(%eax), %ebx
+
+	// check that it is not a pointer to code section
+	// i.e. the following is not true:
+	// __executable_start <= (%eax) <= __etext
+check11:	
+			leal	__executable_start, %edx
+			cmpl	%ebx, %edx
+			jna	check12
+			jmp	check21
+
+check12:	
+			leal	__etext, %edx
+			cmpl	%ebx, %edx
+			jnb	next
+
+	// check that it is not a pointer into the program stack
+	// i.e. the following is not true:
+	// __gc_stack_bottom <= (%eax) <= __gc_stack_top
+check21:	
+			cmpl	%ebx, __gc_stack_top
+			jna	check22
+			jmp	loop2
+
+check22:
+			cmpl	%ebx, __gc_stack_bottom
+			jnb	next
+
+	// check if it a valid pointer
+	// i.e. the lastest bit is set to zero
+loop2:
+			andl	$0x00000001, %ebx
+			jnz     next
+			pushl 	%eax
+			pushl	(%eax)
+        		pushl	$printf_format
+        		call	printf
+        		addl	$8, %esp
+			popl	%eax
+
+next:
+			addl	$4, %eax
+			cmpl	%eax, __gc_stack_bottom
+			jne	loop
+			ret
diff --git a/runtime/runtime.c b/runtime/runtime.c
index dc136ae0b..530990f8b 100644
--- a/runtime/runtime.c
+++ b/runtime/runtime.c
@@ -351,18 +351,24 @@ extern int Lwrite (int n) {
 /* GC starts here */
 
 extern const size_t __gc_data_end, __gc_data_start;
+extern size_t __gc_stack_bottom, __gc_stack_top;
+
+extern void L__gc_init ();
 
 extern void __gc_root_scan_data () {
   size_t * p = &__gc_data_start;
 
-  printf ("Start, end: %d, %d\n", &__gc_data_start, &__gc_data_end);
+  printf ("Start, end: %lx, %lx\n", &__gc_data_start, &__gc_data_end);
   
   while (p != &__gc_data_end) {
-    if (!UNBOXED(*p)) printf ("Root: %d\n", p);
+    if (!UNBOXED(*p)) printf ("Root: %lx\n", *p);
     p++;
   }
 }
 
+extern void __gc_root_scan_stack ();
+
+
 /* extern const void * __gc_data_end, * __gc_data_start; */
 
 /* extern void __gc_root_scan_data () { */
@@ -376,6 +382,17 @@ extern void __gc_root_scan_data () {
 /*   } */
 /* } */
 
+extern char __executable_start;
+extern char __etext;
+
 extern void Ltest () {
+  printf("\n");
+  printf("STA 0x%lx\n", (unsigned long)&__executable_start);
+  printf("END 0x%lx\n", (unsigned long)&__etext);
   __gc_root_scan_data ();
+  __gc_root_scan_stack ();
+
+  //  printf("STA 0x%lx\n", (unsigned long)&__executable_start);
+  //  printf("END 0x%lx\n", (unsigned long)&__etext);
+  //  printf("RET 0x%lx\n\n", __builtin_return_address(0));
 }
diff --git a/runtime/runtime.s b/runtime/runtime.s
new file mode 100644
index 000000000..8181e2ecf
--- /dev/null
+++ b/runtime/runtime.s
@@ -0,0 +1,1640 @@
+	.file	"runtime.c"
+	.text
+	.globl	Blength
+	.type	Blength, @function
+Blength:
+.LFB6:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	subl	$16, %esp
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %eax
+	subl	$4, %eax
+	movl	%eax, -4(%ebp)
+	movl	-4(%ebp), %eax
+	movl	(%eax), %eax
+	addl	%eax, %eax
+	andl	$33554430, %eax
+	orl	$1, %eax
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE6:
+	.size	Blength, .-Blength
+	.globl	de_hash
+	.type	de_hash, @function
+de_hash:
+.LFB7:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$16, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	leal	5+buf.3077@GOTOFF(%eax), %edx
+	movl	%edx, -8(%ebp)
+	movl	-8(%ebp), %edx
+	leal	-1(%edx), %ecx
+	movl	%ecx, -8(%ebp)
+	movb	$0, (%edx)
+	jmp	.L4
+.L5:
+	movl	chars.3076@GOTOFF(%eax), %edx
+	movl	8(%ebp), %ecx
+	andl	$63, %ecx
+	leal	(%edx,%ecx), %ebx
+	movl	-8(%ebp), %edx
+	leal	-1(%edx), %ecx
+	movl	%ecx, -8(%ebp)
+	movzbl	(%ebx), %ecx
+	movb	%cl, (%edx)
+	sarl	$6, 8(%ebp)
+.L4:
+	cmpl	$0, 8(%ebp)
+	jne	.L5
+	addl	$1, -8(%ebp)
+	movl	-8(%ebp), %eax
+	addl	$16, %esp
+	popl	%ebx
+	.cfi_restore 3
+	popl	%ebp
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE7:
+	.size	de_hash, .-de_hash
+	.local	stringBuf
+	.comm	stringBuf,12,4
+	.type	createStringBuf, @function
+createStringBuf:
+.LFB8:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$4, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	subl	$12, %esp
+	pushl	$128
+	call	malloc@PLT
+	addl	$16, %esp
+	movl	%eax, stringBuf@GOTOFF(%ebx)
+	movl	$0, 4+stringBuf@GOTOFF(%ebx)
+	movl	$128, 8+stringBuf@GOTOFF(%ebx)
+	nop
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE8:
+	.size	createStringBuf, .-createStringBuf
+	.type	deleteStringBuf, @function
+deleteStringBuf:
+.LFB9:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$4, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	stringBuf@GOTOFF(%eax), %edx
+	subl	$12, %esp
+	pushl	%edx
+	movl	%eax, %ebx
+	call	free@PLT
+	addl	$16, %esp
+	nop
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE9:
+	.size	deleteStringBuf, .-deleteStringBuf
+	.type	extendStringBuf, @function
+extendStringBuf:
+.LFB10:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$20, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	movl	8+stringBuf@GOTOFF(%ebx), %eax
+	addl	%eax, %eax
+	movl	%eax, -12(%ebp)
+	movl	-12(%ebp), %edx
+	movl	stringBuf@GOTOFF(%ebx), %eax
+	subl	$8, %esp
+	pushl	%edx
+	pushl	%eax
+	call	realloc@PLT
+	addl	$16, %esp
+	movl	%eax, stringBuf@GOTOFF(%ebx)
+	movl	-12(%ebp), %eax
+	movl	%eax, 8+stringBuf@GOTOFF(%ebx)
+	nop
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE10:
+	.size	extendStringBuf, .-extendStringBuf
+	.type	printStringBuf, @function
+printStringBuf:
+.LFB11:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$52, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	movl	8(%ebp), %eax
+	movl	%eax, -44(%ebp)
+	movl	%gs:20, %eax
+	movl	%eax, -12(%ebp)
+	xorl	%eax, %eax
+.L11:
+	leal	12(%ebp), %eax
+	movl	%eax, -28(%ebp)
+	movl	stringBuf@GOTOFF(%ebx), %eax
+	movl	4+stringBuf@GOTOFF(%ebx), %edx
+	addl	%edx, %eax
+	movl	%eax, -24(%ebp)
+	movl	8+stringBuf@GOTOFF(%ebx), %edx
+	movl	4+stringBuf@GOTOFF(%ebx), %eax
+	subl	%eax, %edx
+	movl	%edx, %eax
+	movl	%eax, -20(%ebp)
+	movl	-28(%ebp), %edx
+	movl	-20(%ebp), %eax
+	pushl	%edx
+	pushl	-44(%ebp)
+	pushl	%eax
+	pushl	-24(%ebp)
+	call	vsnprintf@PLT
+	addl	$16, %esp
+	movl	%eax, -16(%ebp)
+	movl	-16(%ebp), %eax
+	cmpl	-20(%ebp), %eax
+	jl	.L12
+	call	extendStringBuf
+	jmp	.L11
+.L12:
+	movl	4+stringBuf@GOTOFF(%ebx), %edx
+	movl	-16(%ebp), %eax
+	addl	%edx, %eax
+	movl	%eax, 4+stringBuf@GOTOFF(%ebx)
+	nop
+	movl	-12(%ebp), %eax
+	xorl	%gs:20, %eax
+	je	.L13
+	call	__stack_chk_fail_local
+.L13:
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE11:
+	.size	printStringBuf, .-printStringBuf
+	.section	.rodata
+.LC0:
+	.string	"%d"
+.LC1:
+	.string	"\"%s\""
+.LC2:
+	.string	"["
+.LC3:
+	.string	", "
+.LC4:
+	.string	"]"
+.LC5:
+	.string	"`%s"
+.LC6:
+	.string	" ("
+.LC7:
+	.string	")"
+.LC8:
+	.string	"*** invalid tag: %x ***"
+	.text
+	.type	printValue, @function
+printValue:
+.LFB12:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$20, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	movl	8(%ebp), %eax
+	andl	$1, %eax
+	testl	%eax, %eax
+	je	.L15
+	movl	8(%ebp), %eax
+	sarl	%eax
+	subl	$8, %esp
+	pushl	%eax
+	leal	.LC0@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printStringBuf
+	addl	$16, %esp
+	jmp	.L28
+.L15:
+	movl	8(%ebp), %eax
+	subl	$4, %eax
+	movl	%eax, -12(%ebp)
+	movl	-12(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$-16777216, %eax
+	cmpl	$16777216, %eax
+	je	.L17
+	cmpl	$33554432, %eax
+	je	.L18
+	testl	%eax, %eax
+	jne	.L19
+	movl	-12(%ebp), %eax
+	addl	$4, %eax
+	subl	$8, %esp
+	pushl	%eax
+	leal	.LC1@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printStringBuf
+	addl	$16, %esp
+	jmp	.L16
+.L17:
+	subl	$12, %esp
+	leal	.LC2@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printStringBuf
+	addl	$16, %esp
+	movl	$0, -20(%ebp)
+	jmp	.L20
+.L22:
+	movl	-12(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	-20(%ebp), %eax
+	sall	$2, %eax
+	addl	%edx, %eax
+	movl	(%eax), %eax
+	subl	$12, %esp
+	pushl	%eax
+	call	printValue
+	addl	$16, %esp
+	movl	-12(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	subl	$1, %eax
+	cmpl	%eax, -20(%ebp)
+	je	.L21
+	subl	$12, %esp
+	leal	.LC3@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printStringBuf
+	addl	$16, %esp
+.L21:
+	addl	$1, -20(%ebp)
+.L20:
+	movl	-12(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	cmpl	%eax, -20(%ebp)
+	jl	.L22
+	subl	$12, %esp
+	leal	.LC4@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printStringBuf
+	addl	$16, %esp
+	jmp	.L16
+.L18:
+	movl	8(%ebp), %eax
+	subl	$8, %eax
+	movl	(%eax), %eax
+	subl	$12, %esp
+	pushl	%eax
+	call	de_hash
+	addl	$16, %esp
+	subl	$8, %esp
+	pushl	%eax
+	leal	.LC5@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printStringBuf
+	addl	$16, %esp
+	movl	-12(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	testl	%eax, %eax
+	je	.L27
+	subl	$12, %esp
+	leal	.LC6@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printStringBuf
+	addl	$16, %esp
+	movl	$0, -16(%ebp)
+	jmp	.L24
+.L26:
+	movl	-12(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	-16(%ebp), %eax
+	sall	$2, %eax
+	addl	%edx, %eax
+	movl	(%eax), %eax
+	subl	$12, %esp
+	pushl	%eax
+	call	printValue
+	addl	$16, %esp
+	movl	-12(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	subl	$1, %eax
+	cmpl	%eax, -16(%ebp)
+	je	.L25
+	subl	$12, %esp
+	leal	.LC3@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printStringBuf
+	addl	$16, %esp
+.L25:
+	addl	$1, -16(%ebp)
+.L24:
+	movl	-12(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	cmpl	%eax, -16(%ebp)
+	jl	.L26
+	subl	$12, %esp
+	leal	.LC7@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printStringBuf
+	addl	$16, %esp
+	jmp	.L27
+.L19:
+	movl	-12(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$-16777216, %eax
+	subl	$8, %esp
+	pushl	%eax
+	leal	.LC8@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printStringBuf
+	addl	$16, %esp
+	jmp	.L28
+.L27:
+	nop
+.L16:
+.L28:
+	nop
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE12:
+	.size	printValue, .-printValue
+	.globl	Belem
+	.type	Belem, @function
+Belem:
+.LFB13:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	subl	$16, %esp
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %eax
+	subl	$4, %eax
+	movl	%eax, -4(%ebp)
+	sarl	12(%ebp)
+	movl	-4(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$-16777216, %eax
+	testl	%eax, %eax
+	jne	.L30
+	movl	-4(%ebp), %edx
+	movl	12(%ebp), %eax
+	addl	%edx, %eax
+	addl	$4, %eax
+	movzbl	(%eax), %eax
+	movsbl	%al, %eax
+	addl	%eax, %eax
+	orl	$1, %eax
+	jmp	.L31
+.L30:
+	movl	-4(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	12(%ebp), %eax
+	sall	$2, %eax
+	addl	%edx, %eax
+	movl	(%eax), %eax
+.L31:
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE13:
+	.size	Belem, .-Belem
+	.globl	Bstring
+	.type	Bstring, @function
+Bstring:
+.LFB14:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$20, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	subl	$12, %esp
+	pushl	8(%ebp)
+	call	strlen@PLT
+	addl	$16, %esp
+	movl	%eax, -16(%ebp)
+	movl	-16(%ebp), %eax
+	addl	$5, %eax
+	subl	$12, %esp
+	pushl	%eax
+	call	malloc@PLT
+	addl	$16, %esp
+	movl	%eax, -12(%ebp)
+	movl	-12(%ebp), %eax
+	movl	-16(%ebp), %edx
+	movl	%edx, (%eax)
+	movl	-16(%ebp), %eax
+	addl	$1, %eax
+	movl	%eax, %edx
+	movl	-12(%ebp), %eax
+	addl	$4, %eax
+	subl	$4, %esp
+	pushl	%edx
+	pushl	8(%ebp)
+	pushl	%eax
+	call	strncpy@PLT
+	addl	$16, %esp
+	movl	-12(%ebp), %eax
+	addl	$4, %eax
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE14:
+	.size	Bstring, .-Bstring
+	.globl	Bstringval
+	.type	Bstringval, @function
+Bstringval:
+.LFB15:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$20, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	call	createStringBuf
+	subl	$12, %esp
+	pushl	8(%ebp)
+	call	printValue
+	addl	$16, %esp
+	movl	stringBuf@GOTOFF(%ebx), %eax
+	subl	$12, %esp
+	pushl	%eax
+	call	Bstring
+	addl	$16, %esp
+	movl	%eax, -12(%ebp)
+	call	deleteStringBuf
+	movl	-12(%ebp), %eax
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE15:
+	.size	Bstringval, .-Bstringval
+	.globl	Barray
+	.type	Barray, @function
+Barray:
+.LFB16:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$36, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	%gs:20, %ecx
+	movl	%ecx, -12(%ebp)
+	xorl	%ecx, %ecx
+	movl	8(%ebp), %edx
+	addl	$1, %edx
+	sall	$2, %edx
+	subl	$12, %esp
+	pushl	%edx
+	movl	%eax, %ebx
+	call	malloc@PLT
+	addl	$16, %esp
+	movl	%eax, -20(%ebp)
+	movl	8(%ebp), %eax
+	orl	$16777216, %eax
+	movl	%eax, %edx
+	movl	-20(%ebp), %eax
+	movl	%edx, (%eax)
+	leal	12(%ebp), %eax
+	movl	%eax, -28(%ebp)
+	movl	$0, -24(%ebp)
+	jmp	.L37
+.L38:
+	movl	-28(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	%edx, -28(%ebp)
+	movl	(%eax), %eax
+	movl	%eax, -16(%ebp)
+	movl	-20(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	-24(%ebp), %eax
+	sall	$2, %eax
+	addl	%eax, %edx
+	movl	-16(%ebp), %eax
+	movl	%eax, (%edx)
+	addl	$1, -24(%ebp)
+.L37:
+	movl	-24(%ebp), %eax
+	cmpl	8(%ebp), %eax
+	jl	.L38
+	movl	-20(%ebp), %eax
+	addl	$4, %eax
+	movl	-12(%ebp), %ecx
+	xorl	%gs:20, %ecx
+	je	.L40
+	call	__stack_chk_fail_local
+.L40:
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE16:
+	.size	Barray, .-Barray
+	.globl	Bsexp
+	.type	Bsexp, @function
+Bsexp:
+.LFB17:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$36, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	%gs:20, %ecx
+	movl	%ecx, -12(%ebp)
+	xorl	%ecx, %ecx
+	movl	8(%ebp), %edx
+	addl	$2, %edx
+	sall	$2, %edx
+	subl	$12, %esp
+	pushl	%edx
+	movl	%eax, %ebx
+	call	malloc@PLT
+	addl	$16, %esp
+	movl	%eax, -24(%ebp)
+	movl	-24(%ebp), %eax
+	addl	$4, %eax
+	movl	%eax, -20(%ebp)
+	movl	8(%ebp), %eax
+	subl	$1, %eax
+	orl	$33554432, %eax
+	movl	%eax, %edx
+	movl	-20(%ebp), %eax
+	movl	%edx, (%eax)
+	leal	12(%ebp), %eax
+	movl	%eax, -32(%ebp)
+	movl	$0, -28(%ebp)
+	jmp	.L42
+.L43:
+	movl	-32(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	%edx, -32(%ebp)
+	movl	(%eax), %eax
+	movl	%eax, -16(%ebp)
+	movl	-20(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	-28(%ebp), %eax
+	sall	$2, %eax
+	addl	%eax, %edx
+	movl	-16(%ebp), %eax
+	movl	%eax, (%edx)
+	addl	$1, -28(%ebp)
+.L42:
+	movl	8(%ebp), %eax
+	subl	$1, %eax
+	cmpl	%eax, -28(%ebp)
+	jl	.L43
+	movl	-32(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	%edx, -32(%ebp)
+	movl	(%eax), %edx
+	movl	-24(%ebp), %eax
+	movl	%edx, (%eax)
+	movl	-20(%ebp), %eax
+	addl	$4, %eax
+	movl	-12(%ebp), %ecx
+	xorl	%gs:20, %ecx
+	je	.L45
+	call	__stack_chk_fail_local
+.L45:
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE17:
+	.size	Bsexp, .-Bsexp
+	.globl	Btag
+	.type	Btag, @function
+Btag:
+.LFB18:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	subl	$16, %esp
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %eax
+	subl	$4, %eax
+	movl	%eax, -4(%ebp)
+	movl	-4(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$-16777216, %eax
+	cmpl	$33554432, %eax
+	jne	.L47
+	movl	8(%ebp), %eax
+	subl	$8, %eax
+	movl	(%eax), %eax
+	cmpl	%eax, 12(%ebp)
+	jne	.L47
+	movl	-4(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	cmpl	%eax, 16(%ebp)
+	jne	.L47
+	movl	$1, %eax
+	jmp	.L48
+.L47:
+	movl	$0, %eax
+.L48:
+	addl	%eax, %eax
+	orl	$1, %eax
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE18:
+	.size	Btag, .-Btag
+	.globl	Barray_patt
+	.type	Barray_patt, @function
+Barray_patt:
+.LFB19:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	subl	$16, %esp
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %eax
+	andl	$1, %eax
+	testl	%eax, %eax
+	je	.L51
+	movl	$1, %eax
+	jmp	.L52
+.L51:
+	movl	8(%ebp), %eax
+	subl	$4, %eax
+	movl	%eax, -4(%ebp)
+	movl	-4(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$-16777216, %eax
+	cmpl	$16777216, %eax
+	jne	.L53
+	movl	-4(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	cmpl	%eax, 12(%ebp)
+	jne	.L53
+	movl	$1, %eax
+	jmp	.L54
+.L53:
+	movl	$0, %eax
+.L54:
+	addl	%eax, %eax
+	orl	$1, %eax
+.L52:
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE19:
+	.size	Barray_patt, .-Barray_patt
+	.globl	Bstring_patt
+	.type	Bstring_patt, @function
+Bstring_patt:
+.LFB20:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$20, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %edx
+	andl	$1, %edx
+	testl	%edx, %edx
+	je	.L56
+	movl	$1, %eax
+	jmp	.L57
+.L56:
+	movl	8(%ebp), %edx
+	subl	$4, %edx
+	movl	%edx, -16(%ebp)
+	movl	12(%ebp), %edx
+	subl	$4, %edx
+	movl	%edx, -12(%ebp)
+	movl	-16(%ebp), %edx
+	movl	(%edx), %edx
+	andl	$-16777216, %edx
+	testl	%edx, %edx
+	je	.L58
+	movl	$1, %eax
+	jmp	.L57
+.L58:
+	movl	-12(%ebp), %edx
+	leal	4(%edx), %ecx
+	movl	-16(%ebp), %edx
+	addl	$4, %edx
+	subl	$8, %esp
+	pushl	%ecx
+	pushl	%edx
+	movl	%eax, %ebx
+	call	strcmp@PLT
+	addl	$16, %esp
+	testl	%eax, %eax
+	jne	.L59
+	movl	$3, %eax
+	jmp	.L57
+.L59:
+	movl	$1, %eax
+.L57:
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE20:
+	.size	Bstring_patt, .-Bstring_patt
+	.globl	Bboxed_patt
+	.type	Bboxed_patt, @function
+Bboxed_patt:
+.LFB21:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %eax
+	andl	$1, %eax
+	testl	%eax, %eax
+	jne	.L62
+	movl	$3, %eax
+	jmp	.L64
+.L62:
+	movl	$1, %eax
+.L64:
+	popl	%ebp
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE21:
+	.size	Bboxed_patt, .-Bboxed_patt
+	.globl	Bunboxed_patt
+	.type	Bunboxed_patt, @function
+Bunboxed_patt:
+.LFB22:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %eax
+	addl	%eax, %eax
+	andl	$2, %eax
+	orl	$1, %eax
+	popl	%ebp
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE22:
+	.size	Bunboxed_patt, .-Bunboxed_patt
+	.globl	Barray_tag_patt
+	.type	Barray_tag_patt, @function
+Barray_tag_patt:
+.LFB23:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %eax
+	andl	$1, %eax
+	testl	%eax, %eax
+	je	.L68
+	movl	$1, %eax
+	jmp	.L69
+.L68:
+	movl	8(%ebp), %eax
+	subl	$4, %eax
+	movl	(%eax), %eax
+	andl	$-16777216, %eax
+	cmpl	$16777216, %eax
+	jne	.L70
+	movl	$3, %eax
+	jmp	.L69
+.L70:
+	movl	$1, %eax
+.L69:
+	popl	%ebp
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE23:
+	.size	Barray_tag_patt, .-Barray_tag_patt
+	.globl	Bstring_tag_patt
+	.type	Bstring_tag_patt, @function
+Bstring_tag_patt:
+.LFB24:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %eax
+	andl	$1, %eax
+	testl	%eax, %eax
+	je	.L73
+	movl	$1, %eax
+	jmp	.L74
+.L73:
+	movl	8(%ebp), %eax
+	subl	$4, %eax
+	movl	(%eax), %eax
+	andl	$-16777216, %eax
+	testl	%eax, %eax
+	jne	.L75
+	movl	$3, %eax
+	jmp	.L74
+.L75:
+	movl	$1, %eax
+.L74:
+	popl	%ebp
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE24:
+	.size	Bstring_tag_patt, .-Bstring_tag_patt
+	.globl	Bsexp_tag_patt
+	.type	Bsexp_tag_patt, @function
+Bsexp_tag_patt:
+.LFB25:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %eax
+	andl	$1, %eax
+	testl	%eax, %eax
+	je	.L78
+	movl	$1, %eax
+	jmp	.L79
+.L78:
+	movl	8(%ebp), %eax
+	subl	$4, %eax
+	movl	(%eax), %eax
+	andl	$-16777216, %eax
+	cmpl	$33554432, %eax
+	jne	.L80
+	movl	$3, %eax
+	jmp	.L79
+.L80:
+	movl	$1, %eax
+.L79:
+	popl	%ebp
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE25:
+	.size	Bsexp_tag_patt, .-Bsexp_tag_patt
+	.globl	Bsta
+	.type	Bsta, @function
+Bsta:
+.LFB26:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	subl	$56, %esp
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	16(%ebp), %eax
+	movl	%eax, -44(%ebp)
+	movl	%gs:20, %eax
+	movl	%eax, -12(%ebp)
+	xorl	%eax, %eax
+	leal	20(%ebp), %eax
+	movl	%eax, -28(%ebp)
+	movl	$0, -24(%ebp)
+	jmp	.L83
+.L84:
+	movl	-28(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	%edx, -28(%ebp)
+	movl	(%eax), %eax
+	sarl	%eax
+	movl	%eax, -20(%ebp)
+	movl	-20(%ebp), %eax
+	leal	0(,%eax,4), %edx
+	movl	-44(%ebp), %eax
+	addl	%edx, %eax
+	movl	(%eax), %eax
+	movl	%eax, -44(%ebp)
+	addl	$1, -24(%ebp)
+.L83:
+	movl	8(%ebp), %eax
+	subl	$1, %eax
+	cmpl	%eax, -24(%ebp)
+	jl	.L84
+	movl	-28(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	%edx, -28(%ebp)
+	movl	(%eax), %eax
+	sarl	%eax
+	movl	%eax, -20(%ebp)
+	movl	-44(%ebp), %eax
+	subl	$4, %eax
+	movl	%eax, -16(%ebp)
+	movl	-16(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$-16777216, %eax
+	testl	%eax, %eax
+	jne	.L85
+	movl	12(%ebp), %eax
+	sarl	%eax
+	movl	%eax, %ecx
+	movl	-20(%ebp), %edx
+	movl	-44(%ebp), %eax
+	addl	%edx, %eax
+	movl	%ecx, %edx
+	movb	%dl, (%eax)
+	jmp	.L88
+.L85:
+	movl	-20(%ebp), %eax
+	leal	0(,%eax,4), %edx
+	movl	-44(%ebp), %eax
+	addl	%eax, %edx
+	movl	12(%ebp), %eax
+	movl	%eax, (%edx)
+.L88:
+	nop
+	movl	-12(%ebp), %eax
+	xorl	%gs:20, %eax
+	je	.L87
+	call	__stack_chk_fail_local
+.L87:
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE26:
+	.size	Bsta, .-Bsta
+	.globl	Lraw
+	.type	Lraw, @function
+Lraw:
+.LFB27:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %eax
+	sarl	%eax
+	popl	%ebp
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE27:
+	.size	Lraw, .-Lraw
+	.globl	Lprintf
+	.type	Lprintf, @function
+Lprintf:
+.LFB28:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$36, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %edx
+	movl	%edx, -28(%ebp)
+	movl	%gs:20, %ecx
+	movl	%ecx, -12(%ebp)
+	xorl	%ecx, %ecx
+	leal	12(%ebp), %edx
+	movl	%edx, -16(%ebp)
+	movl	-16(%ebp), %edx
+	subl	$8, %esp
+	pushl	%edx
+	pushl	-28(%ebp)
+	movl	%eax, %ebx
+	call	vprintf@PLT
+	addl	$16, %esp
+	nop
+	movl	-12(%ebp), %eax
+	xorl	%gs:20, %eax
+	je	.L92
+	call	__stack_chk_fail_local
+.L92:
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE28:
+	.size	Lprintf, .-Lprintf
+	.globl	Lstrcat
+	.type	Lstrcat, @function
+Lstrcat:
+.LFB29:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$20, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	movl	8(%ebp), %eax
+	subl	$4, %eax
+	movl	%eax, -20(%ebp)
+	movl	12(%ebp), %eax
+	subl	$4, %eax
+	movl	%eax, -16(%ebp)
+	movl	-20(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	movl	%eax, %edx
+	movl	-16(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	addl	%edx, %eax
+	addl	$5, %eax
+	subl	$12, %esp
+	pushl	%eax
+	call	malloc@PLT
+	addl	$16, %esp
+	movl	%eax, -12(%ebp)
+	movl	-20(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	movl	%eax, %edx
+	movl	-16(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$16777215, %eax
+	addl	%eax, %edx
+	movl	-12(%ebp), %eax
+	movl	%edx, (%eax)
+	movl	-20(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	-12(%ebp), %eax
+	addl	$4, %eax
+	subl	$8, %esp
+	pushl	%edx
+	pushl	%eax
+	call	strcpy@PLT
+	addl	$16, %esp
+	movl	-16(%ebp), %eax
+	leal	4(%eax), %edx
+	movl	-12(%ebp), %eax
+	addl	$4, %eax
+	subl	$8, %esp
+	pushl	%edx
+	pushl	%eax
+	call	strcat@PLT
+	addl	$16, %esp
+	movl	-12(%ebp), %eax
+	addl	$4, %eax
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE29:
+	.size	Lstrcat, .-Lstrcat
+	.globl	Lfprintf
+	.type	Lfprintf, @function
+Lfprintf:
+.LFB30:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$36, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	movl	8(%ebp), %edx
+	movl	%edx, -28(%ebp)
+	movl	12(%ebp), %edx
+	movl	%edx, -32(%ebp)
+	movl	%gs:20, %ecx
+	movl	%ecx, -12(%ebp)
+	xorl	%ecx, %ecx
+	leal	16(%ebp), %edx
+	movl	%edx, -16(%ebp)
+	movl	-16(%ebp), %edx
+	subl	$4, %esp
+	pushl	%edx
+	pushl	-32(%ebp)
+	pushl	-28(%ebp)
+	movl	%eax, %ebx
+	call	vfprintf@PLT
+	addl	$16, %esp
+	nop
+	movl	-12(%ebp), %eax
+	xorl	%gs:20, %eax
+	je	.L96
+	call	__stack_chk_fail_local
+.L96:
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE30:
+	.size	Lfprintf, .-Lfprintf
+	.globl	Lfopen
+	.type	Lfopen, @function
+Lfopen:
+.LFB31:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$4, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	subl	$8, %esp
+	pushl	12(%ebp)
+	pushl	8(%ebp)
+	movl	%eax, %ebx
+	call	fopen@PLT
+	addl	$16, %esp
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE31:
+	.size	Lfopen, .-Lfopen
+	.globl	Lfclose
+	.type	Lfclose, @function
+Lfclose:
+.LFB32:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$4, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.ax
+	addl	$_GLOBAL_OFFSET_TABLE_, %eax
+	subl	$12, %esp
+	pushl	8(%ebp)
+	movl	%eax, %ebx
+	call	fclose@PLT
+	addl	$16, %esp
+	nop
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE32:
+	.size	Lfclose, .-Lfclose
+	.section	.rodata
+.LC9:
+	.string	"> "
+	.text
+	.globl	Lread
+	.type	Lread, @function
+Lread:
+.LFB33:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$20, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	movl	%gs:20, %eax
+	movl	%eax, -12(%ebp)
+	xorl	%eax, %eax
+	subl	$12, %esp
+	leal	.LC9@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printf@PLT
+	addl	$16, %esp
+	movl	stdout@GOT(%ebx), %eax
+	movl	(%eax), %eax
+	subl	$12, %esp
+	pushl	%eax
+	call	fflush@PLT
+	addl	$16, %esp
+	subl	$8, %esp
+	leal	-16(%ebp), %eax
+	pushl	%eax
+	leal	.LC0@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	__isoc99_scanf@PLT
+	addl	$16, %esp
+	movl	-16(%ebp), %eax
+	addl	%eax, %eax
+	orl	$1, %eax
+	movl	-12(%ebp), %edx
+	xorl	%gs:20, %edx
+	je	.L102
+	call	__stack_chk_fail_local
+.L102:
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE33:
+	.size	Lread, .-Lread
+	.section	.rodata
+.LC10:
+	.string	"%d\n"
+	.text
+	.globl	Lwrite
+	.type	Lwrite, @function
+Lwrite:
+.LFB34:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$4, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	movl	8(%ebp), %eax
+	sarl	%eax
+	subl	$8, %esp
+	pushl	%eax
+	leal	.LC10@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printf@PLT
+	addl	$16, %esp
+	movl	stdout@GOT(%ebx), %eax
+	movl	(%eax), %eax
+	subl	$12, %esp
+	pushl	%eax
+	call	fflush@PLT
+	addl	$16, %esp
+	movl	$0, %eax
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE34:
+	.size	Lwrite, .-Lwrite
+	.section	.rodata
+.LC11:
+	.string	"Start, end: %lx, %lx\n"
+.LC12:
+	.string	"Root: %lx %lx %lx\n"
+	.text
+	.globl	__gc_root_scan_data
+	.type	__gc_root_scan_data, @function
+__gc_root_scan_data:
+.LFB35:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$20, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	movl	%gs:20, %eax
+	movl	%eax, -12(%ebp)
+	xorl	%eax, %eax
+	movl	__gc_data_start@GOT(%ebx), %eax
+	movl	%eax, -16(%ebp)
+	subl	$4, %esp
+	movl	__gc_data_end@GOT(%ebx), %eax
+	pushl	%eax
+	movl	__gc_data_start@GOT(%ebx), %eax
+	pushl	%eax
+	leal	.LC11@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printf@PLT
+	addl	$16, %esp
+	jmp	.L106
+.L108:
+	movl	-16(%ebp), %eax
+	movl	(%eax), %eax
+	andl	$1, %eax
+	testl	%eax, %eax
+	jne	.L107
+	movl	-16(%ebp), %eax
+	movl	(%eax), %edx
+	movl	-16(%ebp), %eax
+	leal	-16(%ebp), %ecx
+	pushl	%ecx
+	pushl	%edx
+	pushl	%eax
+	leal	.LC12@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printf@PLT
+	addl	$16, %esp
+.L107:
+	movl	-16(%ebp), %eax
+	addl	$4, %eax
+	movl	%eax, -16(%ebp)
+.L106:
+	movl	-16(%ebp), %eax
+	movl	__gc_data_end@GOT(%ebx), %edx
+	cmpl	%edx, %eax
+	jne	.L108
+	nop
+	movl	-12(%ebp), %eax
+	xorl	%gs:20, %eax
+	je	.L109
+	call	__stack_chk_fail_local
+.L109:
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE35:
+	.size	__gc_root_scan_data, .-__gc_root_scan_data
+	.section	.rodata
+.LC13:
+	.string	"STA 0x%lx\n"
+	.text
+	.globl	Ltest
+	.type	Ltest, @function
+Ltest:
+.LFB36:
+	.cfi_startproc
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	pushl	%ebx
+	subl	$4, %esp
+	.cfi_offset 3, -12
+	call	__x86.get_pc_thunk.bx
+	addl	$_GLOBAL_OFFSET_TABLE_, %ebx
+	subl	$12, %esp
+	pushl	$10
+	call	putchar@PLT
+	addl	$16, %esp
+	movl	__start_text@GOT(%ebx), %eax
+	subl	$8, %esp
+	pushl	%eax
+	leal	.LC13@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printf@PLT
+	addl	$16, %esp
+	movl	__stop_text@GOT(%ebx), %eax
+	subl	$8, %esp
+	pushl	%eax
+	leal	.LC13@GOTOFF(%ebx), %eax
+	pushl	%eax
+	call	printf@PLT
+	addl	$16, %esp
+	call	__gc_root_scan_data
+	call	__gc_root_scan_stack@PLT
+	nop
+	movl	-4(%ebp), %ebx
+	leave
+	.cfi_restore 5
+	.cfi_restore 3
+	.cfi_def_cfa 4, 4
+	ret
+	.cfi_endproc
+.LFE36:
+	.size	Ltest, .-Ltest
+	.local	buf.3077
+	.comm	buf.3077,6,4
+	.section	.rodata
+	.align 4
+.LC14:
+	.string	"_abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNJPQRSTUVWXYZ"
+	.section	.data.rel.local,"aw"
+	.align 4
+	.type	chars.3076, @object
+	.size	chars.3076, 4
+chars.3076:
+	.long	.LC14
+	.section	.text.__x86.get_pc_thunk.ax,"axG",@progbits,__x86.get_pc_thunk.ax,comdat
+	.globl	__x86.get_pc_thunk.ax
+	.hidden	__x86.get_pc_thunk.ax
+	.type	__x86.get_pc_thunk.ax, @function
+__x86.get_pc_thunk.ax:
+.LFB37:
+	.cfi_startproc
+	movl	(%esp), %eax
+	ret
+	.cfi_endproc
+.LFE37:
+	.section	.text.__x86.get_pc_thunk.bx,"axG",@progbits,__x86.get_pc_thunk.bx,comdat
+	.globl	__x86.get_pc_thunk.bx
+	.hidden	__x86.get_pc_thunk.bx
+	.type	__x86.get_pc_thunk.bx, @function
+__x86.get_pc_thunk.bx:
+.LFB38:
+	.cfi_startproc
+	movl	(%esp), %ebx
+	ret
+	.cfi_endproc
+.LFE38:
+	.hidden	__stack_chk_fail_local
+	.ident	"GCC: (GNU) 8.2.1 20180831"
+	.section	.note.GNU-stack,"",@progbits
diff --git a/src/X86.ml b/src/X86.ml
index 27f6833d4..4fb198f4f 100644
--- a/src/X86.ml
+++ b/src/X86.ml
@@ -19,6 +19,8 @@ let word_size = 4;;
 | L of int     (* an immediate operand             *)
 with show
 
+let show_opnd = show(opnd)
+              
 (* For convenience we define the following synonyms for the registers: *)         
 let ebx = R 0
 let ecx = R 1
@@ -164,7 +166,7 @@ let compile env code =
              (env, Mov (M ("$" ^ s), l) :: call)
              
 	  | LD x ->
-             let s, env' = (env#global x)#allocate in
+             let s, env' = (env#variable x)#allocate in
              env',
 	     (match s with
 	      | S _ | M _ -> [Mov (env'#loc x, eax); Mov (eax, s)]
@@ -172,7 +174,7 @@ let compile env code =
 	     )
                
           | STA (x, n) ->
-             let s, env = (env#global x)#allocate in
+             let s, env = (env#variable x)#allocate in
              let push =
                match s with
                | S _ | M _ -> [Mov (env#loc x, eax); Mov (eax, s)]
@@ -182,7 +184,7 @@ let compile env code =
              env, push @ code
                            
 	  | ST x ->
-	     let s, env' = (env#global x)#pop in
+	     let s, env' = (env#variable x)#pop in
              env',
              (match s with
               | S _ | M _ -> [Mov (s, eax); Mov (eax, env'#loc x)]
@@ -425,13 +427,13 @@ class env =
     (* allocates a fresh position on a symbolic stack *)
     method allocate =    
       let x, n =
-	let rec allocate' = function
-	| []                            -> ebx          , 0
-	| (S n)::_                      -> S (n+1)      , n+2
-	| (R n)::_ when n < num_of_regs -> R (n+1)      , stack_slots
-	| _                             -> S static_size, static_size+1
-	in
-	allocate' stack
+        let rec allocate' = function
+        | []                            -> ebx          , 0
+        | (S n)::_                      -> S (n+1)      , n+2
+        | (R n)::_ when n < num_of_regs -> R (n+1)      , stack_slots
+        | _                             -> S static_size, static_size+1
+        in
+        allocate' stack
       in
       x, {< stack_slots = max n stack_slots; stack = x::stack >}
 
@@ -458,8 +460,11 @@ class env =
       done;
       !h      
              
-    (* registers a global variable in the environment *)
-    method global x  = {< globals = S.add ("global_" ^ x) globals >}
+    (* registers a variable in the environment *)
+    method variable x =
+      match self#loc x with
+      | M name -> {< globals = S.add name globals >}
+      | _      -> self
 
     (* registers a string constant *)
     method string x =
@@ -515,14 +520,24 @@ class env =
    the stack code, then generates x86 assember code, then prints the assembler file
 *)
 let genasm (ds, stmt) =
-  let stmt = Language.Stmt.Seq (stmt, Language.Stmt.Return (Some (Language.Expr.Call ("raw", [Language.Expr.Const 0])))) in
+  let stmt =
+    Language.Stmt.Seq (
+        Language.Stmt.Call ("__gc_init", []),
+        Language.Stmt.Seq (stmt, Language.Stmt.Return (Some (Language.Expr.Call ("raw", [Language.Expr.Const 0]))))
+      )
+  in
   let env, code =
     compile
       (new env)
       ((LABEL "main") :: (BEGIN ("main", [], [])) :: SM.compile (ds, stmt))
   in
-  let data = Meta "\t.data" :: (List.map (fun s      -> Meta (Printf.sprintf "%s:\t.int\t0"         s  )) env#globals) @
-                               (List.map (fun (s, v) -> Meta (Printf.sprintf "%s:\t.string\t\"%s\"" v s)) env#strings) in 
+  let gc_start, gc_end = "__gc_data_start", "__gc_data_end" in
+  let data = [Meta "\t.data"; Meta (Printf.sprintf "\t.globl\t%s" gc_start); Meta (Printf.sprintf "\t.globl\t%s" gc_end)] @
+             [Meta (Printf.sprintf "%s:" gc_start)] @
+             (List.map (fun s      -> Meta (Printf.sprintf "%s:\t.int\t1"         s  )) env#globals) @
+             [Meta (Printf.sprintf "%s:" gc_end)] @
+             (List.map (fun (s, v) -> Meta (Printf.sprintf "%s:\t.string\t\"%s\"" v s)) env#strings)
+  in 
   let asm = Buffer.create 1024 in
   List.iter
     (fun i -> Buffer.add_string asm (Printf.sprintf "%s\n" @@ show i))
@@ -535,5 +550,5 @@ let build prog name =
   Printf.fprintf outf "%s" (genasm prog);
   close_out outf;
   let inc = try Sys.getenv "RC_RUNTIME" with _ -> "../runtime" in
-  Sys.command (Printf.sprintf "gcc -m32 -o %s %s/runtime.o %s.s" name inc name)
+  Sys.command (Printf.sprintf "gcc -g -m32 -o %s %s/gc_runtime.o %s/runtime.o %s.s" name inc inc name)
  
diff --git a/src/testgc.expr b/src/testgc.expr
index 7964e97c7..595eaf0a0 100644
--- a/src/testgc.expr
+++ b/src/testgc.expr
@@ -1,11 +1,22 @@
-x := 0;
-y := 0;
-z := 0;
-t := 0;
-test ();
+fun f () local b {
+  b := 7;
+  test ();
+  b := y;
+  test ();
+  b := 9;
+  test ();
+  return 0
+}
+
+--x := 0;
+--y := 0;
+--z := 0;
+--t := 0;
+--test ();
 y := "abc";
 test ();
 t := [];
 test ();
 t := 0;
-test ()
\ No newline at end of file
+test ();
+f ()