--- a/src/lisp/Config.x86_common
+++ b/src/lisp/Config.x86_common
@@ -43,7 +43,8 @@ CPP_INCLUDE_OPTIONS := -I. -I$(PATH1) -I-
 endif
 
 CPPFLAGS := $(CPP_DEFINE_OPTIONS) $(CPP_INCLUDE_OPTIONS) 
-CFLAGS += -Wstrict-prototypes -Wall -O2 -g -fno-omit-frame-pointer
+CFLAGS += -Wstrict-prototypes -Wall -g -fno-omit-frame-pointer
+CFLAGS += -O2
 ASFLAGS = -g 
 
 ASSEM_SRC = x86-assem.S

--- a/src/lisp/Darwin-os.c
+++ b/src/lisp/Darwin-os.c
@@ -464,8 +464,8 @@ valid_addr(os_vm_address_t addr)
 #ifndef GENCGC
 	|| in_range_p(addr, DYNAMIC_1_SPACE_START, dynamic_space_size)
 #endif
-	|| in_range_p(addr, CONTROL_STACK_START, control_stack_size)
-	|| in_range_p(addr, BINDING_STACK_START, binding_stack_size))
+	|| in_range_p(addr, (lispobj)control_stack, control_stack_size)
+	|| in_range_p(addr, (lispobj)binding_stack, binding_stack_size))
 	return TRUE;
     return FALSE;
 }

--- a/src/lisp/gencgc.c
+++ b/src/lisp/gencgc.c
@@ -166,7 +166,7 @@ check_escaped_stack_object(lispobj * where, lispobj obj)
 
     if (Pointerp(obj)
 	&& (p = (void *) PTR(obj),
-	    (p >= (void *) CONTROL_STACK_START
+	    (p >= (void *) control_stack
 	     && p < (void *) control_stack_end))) {
 	char *space;
 
@@ -195,7 +195,7 @@ check_escaped_stack_object(lispobj * where, lispobj obj)
 	    lose("Escaped stack-allocated object 0x%08lx at %p in %s\n",
 		 (unsigned long) obj, where, space);
 #ifndef i386
-	else if ((where >= (lispobj *) CONTROL_STACK_START
+	else if ((where >= (lispobj *) control_stack
 		  && where < (lispobj *) (control_stack_end))
 		 || (space == NULL)) {
 	    /* Do nothing if it the reference is from the control stack,
@@ -2136,17 +2136,19 @@ read_only_space_p(lispobj obj)
 static inline boolean
 control_stack_space_p(lispobj obj)
 {
-    lispobj end = CONTROL_STACK_START + control_stack_size;
+    char *object = (char *) obj;
+    char *end = (char *)control_stack + control_stack_size;
 
-    return (obj >= CONTROL_STACK_START) && (obj < end);
+    return (object >= (char *) control_stack) && (object < end);
 }
 
 static inline boolean
 binding_stack_space_p(lispobj obj)
 {
-    lispobj end = BINDING_STACK_START + binding_stack_size;
+    char *object = (char *) obj;
+    char *end = (char *)binding_stack + binding_stack_size;
 
-    return (obj >= BINDING_STACK_START) && (obj < end);
+    return (object >= (char *) binding_stack) && (object < end);
 }
     
 static inline boolean
@@ -2157,7 +2159,12 @@ signal_space_p(lispobj obj)
 
     return (obj >= SIGNAL_STACK_START) && (obj < end);
 #else
-    return FALSE;
+    extern char altstack[];
+    
+    char* object = (char*) obj;
+    char* end = altstack + SIGNAL_STACK_SIZE;
+    
+    return (object >= altstack && object < end);
 #endif    
 }
 
@@ -7322,11 +7329,11 @@ verify_gc(void)
     int static_space_size = (lispobj *) SymbolValue(STATIC_SPACE_FREE_POINTER)
 	- (lispobj *) static_space;
     int binding_stack_size = (lispobj *) get_binding_stack_pointer()
-	- (lispobj *) BINDING_STACK_START;
+	- (lispobj *) binding_stack;
 
     verify_space((lispobj *) READ_ONLY_SPACE_START, read_only_space_size);
     verify_space((lispobj *) static_space, static_space_size);
-    verify_space((lispobj *) BINDING_STACK_START, binding_stack_size);
+    verify_space((lispobj *) binding_stack, binding_stack_size);
     verify_space((lispobj *) (void *) &scavenger_hooks, 1);
 }
 
@@ -7523,7 +7530,7 @@ garbage_collect_generation(int generation, int raise)
 
 #ifdef GC_ASSERTIONS
 #if defined(i386) || defined(__x86_64)
-    invalid_stack_start = (void *) CONTROL_STACK_START;
+    invalid_stack_start = (void *) control_stack;
     invalid_stack_end = (void *) &raise;
 #else /* not i386 */
     invalid_stack_start = (void *) &raise;

--- a/src/lisp/interrupt.c
+++ b/src/lisp/interrupt.c
@@ -408,10 +408,10 @@ interrupt_maybe_gc(HANDLER_ARGS)
 * Noise to install handlers.                                     *
 \****************************************************************/
 
-#if !(defined(i386) || defined(__x86_64))
-#define SIGNAL_STACK_SIZE SIGSTKSZ
-static char altstack[SIGNAL_STACK_SIZE];
-#endif
+//#if !(defined(i386) || defined(__x86_64))
+//#define SIGNAL_STACK_SIZE SIGSTKSZ
+char altstack[SIGNAL_STACK_SIZE];
+//#endif
 
 void
 interrupt_install_low_level_handler(int signal, void handler(HANDLER_ARGS))
@@ -434,7 +434,7 @@ interrupt_install_low_level_handler(int signal, void handler(HANDLER_ARGS))
     if (signal == PROTECTION_VIOLATION_SIGNAL) {
 	stack_t sigstack;
 
-#if (defined( i386 ) || defined(__x86_64))
+#if defined(SIGNAL_STACK_START)
 	sigstack.ss_sp = (void *) SIGNAL_STACK_START;
 #else
 	sigstack.ss_sp = (void *) altstack;

--- a/src/lisp/ppc-validate.h
+++ b/src/lisp/ppc-validate.h
@@ -41,11 +41,17 @@
 #define STATIC_SPACE_START  	(0x10000000)
 #define STATIC_SPACE_SIZE   	(0x07ff8000)	/* 128 MB, almost */
 
+#if 0
 #define CONTROL_STACK_START 	(0x30000000)
+#endif
 #define CONTROL_STACK_SIZE  	(0x07ff8000)	/* 128 MB, almost */
+#if 0
 #define CONTROL_STACK_END       (CONTROL_STACK_START + control_stack_size)
+#endif
 
+#if 0
 #define BINDING_STACK_START 	(0x38000000)
+#endif
 #define BINDING_STACK_SIZE  	(0x07ff8000)	/* 128 MB, almost */
 
 #if 0

--- a/src/lisp/sparc-validate.h
+++ b/src/lisp/sparc-validate.h
@@ -92,15 +92,22 @@
 #define READ_ONLY_SPACE_START	(SpaceStart_TargetReadOnly)
 #define READ_ONLY_SPACE_SIZE	((2*MB_128) - SPARSE_BLOCK_SIZE)	/* 256 MB - 32 KB, 256 MB max */
 
+#if 0
 #define BINDING_STACK_START 	(0x20000000)
+#endif
+
 #define BINDING_STACK_SIZE  	(MB_128 - SPARSE_BLOCK_SIZE)	/* 128 MB - 32 KB, 128 MB max */
 
 #define STATIC_SPACE_START  	(SpaceStart_TargetStatic)
 #define STATIC_SPACE_SIZE   	((2*MB_128) - SPARSE_BLOCK_SIZE)	/* 256 MB - 32 KB, 256 MB max */
 
+#if 0
 #define CONTROL_STACK_START 	(0x38000000)
+#endif
 #define CONTROL_STACK_SIZE  	(MB_128 - SPARSE_BLOCK_SIZE)	/* 128 MB - 32 KB, 128 MB max */
+#if 0
 #define CONTROL_STACK_END       (CONTROL_STACK_START + control_stack_size)
+#endif
 
 #define DYNAMIC_0_SPACE_START	(SpaceStart_TargetDynamic)
 

--- a/src/lisp/x86-assem.S
+++ b/src/lisp/x86-assem.S
@@ -143,7 +143,8 @@ FUNCDEF(call_into_lisp)
 	movl	%eax, GNAME(foreign_function_call_active)
 
 	movl	%esp,%ebx	# remember current stack
-	cmpl	$CONTROL_STACK_START,%esp
+	cmpl	GNAME(control_stack), %esp
+
 	jbe	ChangeToLispStack
 	cmpl	GNAME(control_stack_end), %esp
 	jbe	OnLispStack

--- a/src/lisp/x86-validate-darwin.h
+++ b/src/lisp/x86-validate-darwin.h
@@ -18,10 +18,14 @@
 #define STATIC_SPACE_START	(SpaceStart_TargetStatic)
 #define STATIC_SPACE_SIZE	(0x0ffff000)	/* 256MB - 1 page */
 
+#if 0
 #define BINDING_STACK_START	(0x38000000)
+#endif
 #define BINDING_STACK_SIZE	(0x07fff000)	/* 128MB - 1 page */
 
+#if 0
 #define CONTROL_STACK_START	(0x40000000)
+#endif
 
 /*
  * According to /usr/include/sys/signal.h, MINSIGSTKSZ is 32K and
@@ -29,7 +33,9 @@
  */
 #define CONTROL_STACK_SIZE	(0x07fdf000)	/* 128MB - SIGSTKSZ - 1 page */
 
+#if 0
 #define SIGNAL_STACK_START	(0x47fe0000)    /* One page past the end of the control stack */
+#endif
 #define SIGNAL_STACK_SIZE	SIGSTKSZ
 
 #define DYNAMIC_0_SPACE_START	(SpaceStart_TargetDynamic)

--- a/src/lisp/x86-validate-linux.h
+++ b/src/lisp/x86-validate-linux.h
@@ -36,13 +36,19 @@
 #define STATIC_SPACE_START	(SpaceStart_TargetStatic)
 #define STATIC_SPACE_SIZE	(0x0ffff000)	/* 256MB - 1 page */
 
+#if 0
 #define BINDING_STACK_START	(0x20000000)
+#endif
 #define BINDING_STACK_SIZE	(0x07fff000)	/* 128MB - 1 page */
 
+#if 0
 #define CONTROL_STACK_START	0x38000000
+#endif
 #define CONTROL_STACK_SIZE	(0x07fff000 - 8192)
 
+#if 0
 #define SIGNAL_STACK_START	CONTROL_STACK_END
+#endif
 #define SIGNAL_STACK_SIZE	SIGSTKSZ
 
 #define DYNAMIC_0_SPACE_START	(SpaceStart_TargetDynamic)