--- Libc/Libc-262.3.2/ppc/sys/_setjmp.h
+++ Libc/Libc-498/ppc/sys/_setjmp.h
@@ -2,8 +2,6 @@
  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
  *
  * @APPLE_LICENSE_HEADER_START@
- * 
- * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
  * 
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
@@ -37,7 +35,18 @@
  * is bcopy'd to a different alignment between the setjmp
  * and longjmp, we need to save the jmp_buf address in the
  * jmp_buf at setjmp time, so we can realign before reloading.
+ *
+ * ALSO NOTE: the typedef for jmpbufs in <ppc/setjmp.h> is
+ * 192 ints (0x300 bytes) long, due to incorrectly assuming
+ * that we need to save all 32 VRs in a jmpbuf.  This is
+ * fortuitous, because when it came time to add additional
+ * fields and expand GPRs for 64-bit mode, there was plenty
+ * of unused space!
  */
+ 
+ /* 32-bit-mode layout */
+ 
+#if defined(__ppc__)
  
 #define JMP_r1	0x00
 #define JMP_r2	0x04
@@ -62,11 +71,9 @@
 #define JMP_r31	0x50
 #define JMP_lr  0x54
 #define JMP_cr  0x58
-#define JMP_ctr	0x5c
-#define JMP_xer	0x60
-#define JMP_sig	0x64
-#define JMP_SIGFLAG 0x68
-#define JMP_flags 0x6c
+#define JMP_SIGFLAG 0x5c
+#define JMP_sig	0x60    /* reserve 8 bytes for sigmask */
+#define JMP_fpscr  0x68 /* reserve 8 bytes for FPSCR too */
 #define JMP_vrsave 0x70
 #define JMP_addr_at_setjmp 0x74
 /* 12 bytes padding here */
@@ -74,5 +81,50 @@
 /* save room for 12 VRs (v20-v31), or 0xC0 bytes */
 #define JMP_fp_base_addr 0x144
 /* save room for 18 FPRs (f14-f31), or 0x90 bytes */
-#define JMP_buf_end 0x1d4
+#define	JMP_ss_flags	 0x1d4
+#define JMP_buf_end 0x1d8
 
+ 
+ /* 64-bit-mode layout */
+
+#elif defined(__ppc64__)
+
+#define JMP_r1	0x00
+#define JMP_r2	0x08
+#define JMP_r13	0x10
+#define JMP_r14	0x18
+#define JMP_r15	0x20
+#define JMP_r16	0x28
+#define JMP_r17	0x30
+#define JMP_r18	0x38
+#define JMP_r19	0x40
+#define JMP_r20	0x48
+#define JMP_r21	0x50
+#define JMP_r22	0x58
+#define JMP_r23	0x60
+#define JMP_r24	0x68
+#define JMP_r25	0x70
+#define JMP_r26	0x78
+#define JMP_r27	0x80
+#define JMP_r28	0x88
+#define JMP_r29	0x90
+#define JMP_r30	0x98
+#define JMP_r31	0xa0
+#define JMP_lr  0xa8
+#define JMP_cr  0xb0
+#define JMP_sig	0xb8
+#define JMP_SIGFLAG 0xc0
+#define JMP_fpscr  0xc8
+#define JMP_vrsave 0xd0
+#define JMP_addr_at_setjmp 0xd8
+/* 12 bytes padding here */
+#define JMP_vr_base_addr 0x0ec
+/* save room for 12 VRs (v20-v31), or 0xC0 bytes */
+#define JMP_fp_base_addr 0x1ac
+/* save room for 18 FPRs (f14-f31), or 0x90 bytes */
+#define	JMP_ss_flags	 0x23c
+#define JMP_buf_end 0x240
+
+#else
+#error architecture not supported
+#endif