+;;; Note: Mostly these values are black magic, inherited from CMU CL
+;;; without any documentation. However, there were a few explanatory
+;;; comments in the CMU CL sources:
+;;; * On Linux,
+;;; ** The space 0x08000000-0x10000000 is "C program and memory allocation".
+;;; ** The space 0x40000000-0x48000000 is reserved for shared libs.
+;;; ** The space >0xE0000000 is "C stack - Alien stack".
+;;; * On FreeBSD,
+;;; ** The space 0x0E000000-0x10000000 is "Foreign segment".
+;;; ** The space 0x20000000-0x30000000 is reserved for shared libs.
+;;; And there have been some changes since the fork from CMU CL:
+;;; * The OpenBSD port is new since the fork. We started with
+;;; the FreeBSD address map, which actually worked until the
+;;; Alpha port patches, for reasons which in retrospect are rather
+;;; mysterious. After the Alpha port patches were added, the
+;;; OpenBSD port suffered memory corruption problems. While
+;;; debugging those, it was discovered that src/runtime/trymap
+;;; failed for the control stack region #x40000000-#x47fff000.
+;;; After the control stack was moved upward out of this region
+;;; (stealing some bytes from dynamic space) the problems went
+;;; away.
+;;; * The FreeBSD STATIC-SPACE-START value was bumped up from
+;;; #x28000000 to #x30000000 when FreeBSD ld.so dynamic linking
+;;; support was added for FreeBSD ca. 20000910. This was to keep from
+;;; stomping on an address range that the dynamic libraries want to
+;;; use. (They want to use this address range even if we try to
+;;; reserve it with a call to validate() as the first operation in
+;;; main().)
+;;; * For NetBSD 2.0, the following ranges are used by normal
+;;; executables and mmap:
+;;; ** Executables are (by default) loaded at 0x08048000.
+;;; ** The break for the sbcl runtime seems to end around 0x08400000
+;;; We set read only space around 0x20000000, static
+;;; space around 0x30000000, all ending below 0x37fff000
+;;; ** ld.so and other mmap'ed stuff like shared libs start around
+;;; 0x48000000
+;;; We set dynamic space between 0x60000000 and 0x98000000
+;;; ** Bottom of the stack is typically not below 0xb0000000
+;;; FYI, this can be looked at with the "pmap" program, and if you
+;;; set the top-down mmap allocation option in the kernel (not yet
+;;; the default), all bets are totally off!
+
+#!+linux
+(progn
+ (def!constant read-only-space-start #x01000000)
+ (def!constant read-only-space-end #x037ff000)
+
+ (def!constant static-space-start #x05000000)
+ (def!constant static-space-end #x07fff000)
+
+ (def!constant dynamic-space-start #x09000000)
+ (def!constant dynamic-space-end #x29000000)
+
+ (def!constant linkage-table-space-start #x70000000)
+ (def!constant linkage-table-space-end #x7ffff000))
+
+#!+freebsd
+(progn
+ (def!constant read-only-space-start #x10000000)
+ (def!constant read-only-space-end #x1ffff000)
+
+ (def!constant static-space-start #x30000000)
+ (def!constant static-space-end #x37fff000)
+
+ (def!constant dynamic-space-start #x48000000)
+ (def!constant dynamic-space-end #x88000000)
+
+ ;; In CMUCL: 0xB0000000->0xB1000000
+ (def!constant linkage-table-space-start #x90000000)
+ (def!constant linkage-table-space-end #x91000000))
+
+#!+openbsd
+(progn
+ (def!constant read-only-space-start #x40000000)
+ (def!constant read-only-space-end #x47fff000)
+
+ (def!constant static-space-start #x50000000)
+ (def!constant static-space-end #x5ffff000)
+
+ (def!constant dynamic-space-start #x80000000)
+ (def!constant dynamic-space-end #xA0000000)
+
+ ;; In CMUCL: 0xB0000000->0xB1000000
+ (def!constant linkage-table-space-start #xA0000000)
+ (def!constant linkage-table-space-end #xA1000000))
+
+#!+netbsd
+(progn
+ (def!constant read-only-space-start #x20000000)
+ (def!constant read-only-space-end #x2ffff000)
+
+ (def!constant static-space-start #x30000000)
+ (def!constant static-space-end #x37fff000)
+
+ (def!constant dynamic-space-start #x60000000)
+ (def!constant dynamic-space-end #x98000000)
+
+ ;; In CMUCL: 0xB0000000->0xB1000000
+ (def!constant linkage-table-space-start #xA0000000)
+ (def!constant linkage-table-space-end #xA1000000))
+
+;;; Size of one linkage-table entry in bytes.
+(def!constant linkage-table-entry-size 8)
+
+;;; Given that NIL is the first thing allocated in static space, we