gnu: racket: Update to 8.6.

Also, update 'chez-scheme-for-racket' to 9.5.9.2.

* gnu/packages/patches/racket-chez-scheme-bin-sh.patch: Refresh patch.
* gnu/packages/patches/racket-backport-8.6-cross-install.patch,
gnu/packages/patches/racket-backport-8.6-docindex-write.patch,
gnu/packages/patches/racket-backport-8.6-hurd.patch: New patches.
* gnu/local.mk (dist_patch_DATA): Add them.
* gnu/packages/racket.scm (%racket-origin)[patches]: Use them and the
patches for Zuo.
(%racket-version): Update to 8.6.
(zuo)[version]: Refer to '%racket-version'.
[origin]: Use '%racket-origin'.
(racket-vm-cgc)[native-inputs]: Add 'zuo'.
[arguments]<#:make-flags>: Use 'zuo' from 'native-inputs'.
(racket)[inputs]<data, db, deinprogramm, draw, drracket, errortrace,
gui, htdp, math, option-contract, parser-tools, pict, rackunit, realm,
redex, scribble, typed-racket, string-constants, swindle, syntax-color,
web-server>: Update checksums.
* gnu/packages/chez.scm (target-chez-os): Handle Hurd and QNX.
(%chez-features-table): Likewise.
(chez-scheme-for-racket): Update to 9.5.9.2.
[native-inputs]: Add 'zuo'.
[arguments]<#:out-of-source?>: Use out-of-source build.
<#:tests?>: Skip them due to ongoing problems.
<#:configure-flags>: Add '--install-csug=' and '--installreleasenotes='.
<#:make-flags>: Use 'zuo' from 'native-inputs'. Supply 'STEXLIB=' here,
rather than in a phase.
<#:phases>: Replace 'install-docs' using new 'make' target.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

6 files changed, 893 insertions, 77 deletions

diff --git a/gnu/packages/chez.scm b/gnu/packages/chez.scm
index c627c4d842..b59398578a 100644
--- a/gnu/packages/chez.scm
+++ b/gnu/packages/chez.scm
@@ -115,7 +115,7 @@ in Chez Scheme machine types, or '#f' if none is defined."
    ((target-linux? system)
     "le")
    ((target-hurd? system)
-    #f)
+    "gnu")
    ((target-mingw? system)
     "nt")
    ;; missing (guix utils) predicates
@@ -131,6 +131,8 @@ in Chez Scheme machine types, or '#f' if none is defined."
    ;; Nix says "x86_64-solaris", but accommodate "-solaris2"
    ((string-contains system "solaris")
     "s2")
+   ((string-suffix? "-qnx" system)
+    "qnx")
    ;; unknown
    (else
     #f)))
@@ -167,6 +169,9 @@ in Chez Scheme machine types, or '#f' if none is defined."
      ("arm32" bootstrap-bootfiles)
      ("arm64" . #f)
      ("ppc32" threads))
+    ;; Hurd
+    ("gnu"
+     ("i3" . #f))
     ;; FreeBSD
     ("fb"
      ("i3" threads) ;; commented out
@@ -192,6 +197,9 @@ in Chez Scheme machine types, or '#f' if none is defined."
     ("s2"
      ("i3" threads) ;; commented out
      ("a6" threads)) ;; commented out
+    ;; QNX
+    ("qnx"
+     ("i3" . #f))
     ;; Windows
     ("nt"
      ("i3" threads bootstrap-bootfiles)
@@ -433,7 +441,7 @@ and 32-bit PowerPC architectures.")
   (package
     (inherit chez-scheme)
     (name "chez-scheme-for-racket")
-    (version "9.5.7.6")
+    (version "9.5.9.2")
     ;; The version should match `(scheme-fork-version-number)`.
     ;; See racket/src/ChezScheme/s/cmacros.ss c. line 360.
     ;; It will always be different than the upstream version!
@@ -444,18 +452,52 @@ and 32-bit PowerPC architectures.")
        (delete "libx11" "util-linux:lib")))
     (native-inputs
      (modify-inputs (package-native-inputs chez-scheme)
+       (prepend zuo)
        (replace "chez-scheme-bootstrap-bootfiles"
          chez-scheme-for-racket-bootstrap-bootfiles)))
     (arguments
      (substitute-keyword-arguments (package-arguments chez-scheme)
+       ((#:out-of-source? _ #f)
+        #t)
+       ((#:tests? _ #t)
+        ;; FIXME: There have been some flaky test failures. Some have been
+        ;; fixed upstream post-release but have proven non-trivial to
+        ;; backport; at least one issue remains. Re-enable tests once
+        ;; https://github.com/racket/racket/issues/4359 is fixed.
+        #f)
        ((#:configure-flags cfg-flags #~'())
-        #~(cons* "--disable-x11"
-                 "--threads" ;; ok to potentially duplicate
-                 #$cfg-flags))
+        #~`("--disable-x11"
+            "--threads" ;; ok to potentially duplicate
+            ,@(let* ((chez+version (strip-store-file-name #$output))
+                     (doc-prefix (assoc-ref %outputs "doc"))
+                     (doc-dir (string-append doc-prefix
+                                             "/share/doc/"
+                                             chez+version)))
+                (list (string-append "--installcsug="
+                                     doc-dir
+                                     "/csug")
+                      (string-append "--installreleasenotes="
+                                     doc-dir
+                                     "/release_notes")))
+            ,@#$cfg-flags))
+       ((#:make-flags mk-flags #~'())
+        #~(cons* (string-append "ZUO="
+                                #+(this-package-native-input "zuo")
+                                "/bin/zuo")
+                 (string-append "STEXLIB="
+                                #+(this-package-native-input "stex")
+                                "/lib/stex")
+                 #$mk-flags))
        ((#:phases those-phases #~%standard-phases)
         #~(let* ((those-phases #$those-phases)
                  (unpack (assoc-ref those-phases 'unpack)))
             (modify-phases those-phases
+              (replace 'install-docs
+                (lambda* (#:key make-flags #:allow-other-keys)
+                  (apply invoke
+                         "make"
+                         "install-docs"
+                         make-flags)))
               (replace 'unpack
                 (lambda args
                   (unpack #:source #$(or (package-source this-package)
diff --git a/gnu/packages/patches/racket-backport-8.6-cross-install.patch b/gnu/packages/patches/racket-backport-8.6-cross-install.patch
new file mode 100644
index 0000000000..2c4d8924ed
--- /dev/null
+++ b/gnu/packages/patches/racket-backport-8.6-cross-install.patch
@@ -0,0 +1,126 @@
+From fbe2094f56fb81c888076c781e90fb0abbc0cc07 Mon Sep 17 00:00:00 2001
+From: Matthew Flatt <mflatt@racket-lang.org>
+Date: Sat, 30 Jul 2022 07:06:55 -0600
+Subject: [PATCH 1/2] CS makefiles: fix Unix-style install for cross
+ compilation
+
+Closes #4377
+
+(cherry picked from commit 053be470e7c5454cdf48e934f3254d2d916bbbc5)
+---
+ racket/src/cs/c/build.zuo | 5 ++---
+ 1 file changed, 2 insertions(+), 3 deletions(-)
+
+diff --git a/racket/src/cs/c/build.zuo b/racket/src/cs/c/build.zuo
+index 8d3950bb27..d8b74c509d 100644
+--- a/racket/src/cs/c/build.zuo
++++ b/racket/src/cs/c/build.zuo
+@@ -1016,10 +1016,9 @@
+   (define (setup)
+     (call-with-dest-racket
+      (lambda (bindir dest-racket)
+-       (define copytree-racket (and cross? (config-bootstrap-racket)))
++       (define copytree-racket (and cross? (hash-ref (config-bootstrap-racket) 'racket)))
+        (maybe-copytree config dest-racket copytree-racket at-dir)
+-       (run-raco-setup config dest-racket
+-                       (and cross? (hash-ref (config-bootstrap-racket) 'racket))
++       (run-raco-setup config dest-racket copytree-racket
+                        ;; this can be redundant if it's also supplied via `SETUP_MACHINE_FLAGS`,
+                        ;; but redundant should be ok:
+                        (list "-MCR" (~a (at-dir "compiled") ":")
+-- 
+2.32.0
+
+
+From 85802f4d515e310e657928707800ad709a676e2a Mon Sep 17 00:00:00 2001
+From: Matthew Flatt <mflatt@racket-lang.org>
+Date: Mon, 15 Aug 2022 10:37:01 +0800
+Subject: [PATCH 2/2] configure: adjust cross-build assumption for a pb build
+
+Don't assume a cross build for a pb target on a platform that's only
+supported via pb.
+
+(cherry picked from commit 70e484e885637c495be5481983dae2207fdd67bb)
+
+(Edited to remove unrelated tweak to comments in
+"racket/src/expander/expand/require+provide.rkt".)
+---
+ racket/src/cs/c/configure    | 15 +++++++++++----
+ racket/src/cs/c/configure.ac | 15 +++++++++++----
+ 2 files changed, 22 insertions(+), 8 deletions(-)
+
+diff --git a/racket/src/cs/c/configure b/racket/src/cs/c/configure
+index 454d79e11a..7e0fa5600d 100755
+--- a/racket/src/cs/c/configure
++++ b/racket/src/cs/c/configure
+@@ -4679,6 +4679,11 @@ case "$MACH_HOST_CPU" in
+     ;;
+ esac
+ 
++if test "${MACH}" = "" ; then
++  default_mach_was_empty=yes
++else
++  default_mach_was_empty=no
++fi
+ 
+ if test "${enable_mach}" != "" ; then
+   MACH="${enable_mach}"
+@@ -4701,13 +4706,15 @@ elif test "$MACH" = "" -o "$MACH_OS" = "" ; then
+    exit 1
+ fi
+ 
+-# For a pb build where Racket is supplied, force cross-build
+-# mode on the assumption that the host is not a pb build
+-# (because it should be created with default configure options)
++# For a pb build where Racket is supplied and MACH was not originally
++# empty, force cross-build mode on the assumption that the host is not
++# a pb build (because it should be created with default configure options)
+ if test "${enable_pb}" = "yes" ; then
+   if test "${enable_racket}" != "" ; then
+     if test "${enable_target}" = "" ; then
+-      enable_target="${MACH}"
++      if test "${default_mach_was_empty}" = "no" ; then
++        enable_target="${MACH}"
++      fi
+     fi
+   fi
+ fi
+diff --git a/racket/src/cs/c/configure.ac b/racket/src/cs/c/configure.ac
+index 5bce979c92..734c1e8feb 100644
+--- a/racket/src/cs/c/configure.ac
++++ b/racket/src/cs/c/configure.ac
+@@ -415,6 +415,11 @@ case "$MACH_HOST_CPU" in
+     ;;
+ esac
+ 
++if test "${MACH}" = "" ; then
++  default_mach_was_empty=yes
++else
++  default_mach_was_empty=no
++fi
+ 
+ if test "${enable_mach}" != "" ; then
+   MACH="${enable_mach}"
+@@ -437,13 +442,15 @@ elif test "$MACH" = "" -o "$MACH_OS" = "" ; then
+    exit 1
+ fi
+ 
+-# For a pb build where Racket is supplied, force cross-build
+-# mode on the assumption that the host is not a pb build
+-# (because it should be created with default configure options)
++# For a pb build where Racket is supplied and MACH was not originally
++# empty, force cross-build mode on the assumption that the host is not
++# a pb build (because it should be created with default configure options)
+ if test "${enable_pb}" = "yes" ; then
+   if test "${enable_racket}" != "" ; then
+     if test "${enable_target}" = "" ; then
+-      enable_target="${MACH}"
++      if test "${default_mach_was_empty}" = "no" ; then
++        enable_target="${MACH}"
++      fi
+     fi
+   fi
+ fi
+-- 
+2.32.0
+
diff --git a/gnu/packages/patches/racket-backport-8.6-docindex-write.patch b/gnu/packages/patches/racket-backport-8.6-docindex-write.patch
new file mode 100644
index 0000000000..abe1984507
--- /dev/null
+++ b/gnu/packages/patches/racket-backport-8.6-docindex-write.patch
@@ -0,0 +1,36 @@
+From 8b4d686a62fd66dedfc40ecdcf3698316993d614 Mon Sep 17 00:00:00 2001
+From: Philip McGrath <philip@philipmcgrath.com>
+Date: Sun, 17 Jul 2022 22:51:44 -0400
+Subject: [PATCH] racket-index: set write permission when copying
+ `docindex.sqlite`
+
+Fixes https://github.com/racket/racket/issues/4357
+
+(cherry picked from commit 55b6cbdca1f36a4f37bab1519c1b658717d3cad2)
+---
+ pkgs/racket-index/setup/scribble.rkt | 9 ++++++++-
+ 1 file changed, 8 insertions(+), 1 deletion(-)
+
+diff --git a/pkgs/racket-index/setup/scribble.rkt b/pkgs/racket-index/setup/scribble.rkt
+index 6694f0b793..e27a8fa348 100644
+--- a/pkgs/racket-index/setup/scribble.rkt
++++ b/pkgs/racket-index/setup/scribble.rkt
+@@ -252,7 +252,14 @@
+     (unless (file-exists? db-file)
+       (define-values (base name dir?) (split-path db-file))
+       (make-directory* base)
+-      (when copy-from (copy-file copy-from db-file))
++      (when copy-from
++        (copy-file copy-from db-file)
++        ;; we might not have write permissions for the previous layer:
++        ;; ensure that we do for the new file
++        (define orig-mode (file-or-directory-permissions db-file 'bits))
++        (define writeable-mode (bitwise-ior user-write-bit orig-mode))
++        (unless (= writeable-mode orig-mode)
++          (file-or-directory-permissions db-file writeable-mode)))
+       (doc-db-disconnect
+        (doc-db-file->connection db-file #t))))
+   (when (or (ormap can-build*? main-docs)
+-- 
+2.32.0
+
diff --git a/gnu/packages/patches/racket-backport-8.6-hurd.patch b/gnu/packages/patches/racket-backport-8.6-hurd.patch
new file mode 100644
index 0000000000..d593b01e62
--- /dev/null
+++ b/gnu/packages/patches/racket-backport-8.6-hurd.patch
@@ -0,0 +1,609 @@
+From f17b030fa2f902bb3666913d4a3cd6ba9c146d22 Mon Sep 17 00:00:00 2001
+From: Philip McGrath <philip@philipmcgrath.com>
+Date: Wed, 3 Aug 2022 03:13:03 -0400
+Subject: [PATCH 1/3] Chez Scheme: Fix build on GNU/Hurd
+
+Mostly GNU/Hurd should take the same options as GNU/Linux. One
+difference is that the Hurd does not define macros such as `PATH_MAX` or
+`NOFILE`, because it avoids imposing arbitrary limits on such resources.
+This patch provides alternatives for localized uses of those constants,
+but it accepts the pervasive use of `PATH_MAX` in finding bootfiles for
+now. See https://www.gnu.org/software/hurd/hurd/porting/guidelines.html.
+
+(cherry picked from commit 87eee6e2adb8c6bc11e60619c706fa6295096085)
+---
+ racket/src/ChezScheme/README.md    |  1 +
+ racket/src/ChezScheme/c/number.c   | 22 +++++++++----------
+ racket/src/ChezScheme/c/prim5.c    | 35 ++++++++++++++++++++++++++++--
+ racket/src/ChezScheme/c/scheme.c   | 34 +++++++++++++++++------------
+ racket/src/ChezScheme/c/version.h  |  7 ++++--
+ racket/src/ChezScheme/configure    | 17 ++++++++++-----
+ racket/src/ChezScheme/s/cmacros.ss |  1 +
+ racket/src/cs/c/configure          | 14 ++++++++++--
+ racket/src/cs/c/configure.ac       | 14 ++++++++++--
+ racket/src/cs/rumble/system.ss     |  3 +++
+ 10 files changed, 109 insertions(+), 39 deletions(-)
+
+diff --git a/racket/src/ChezScheme/README.md b/racket/src/ChezScheme/README.md
+index a4a11a5eef..25231dd9bb 100644
+--- a/racket/src/ChezScheme/README.md
++++ b/racket/src/ChezScheme/README.md
+@@ -13,6 +13,7 @@ Supported platforms (bytecode interpreter may work for others):
+  * OpenBSD: x86, x86_64, ARMv6, AArch64, PowerPC32
+  * NetBSD: x86, x86_64, ARMv6, AArch64, PowerPC32
+  * Solaris: x86, x86_64
++ * GNU/Hurd: x86
+  * Android: ARMv7, AArch64
+  * iOS: AArch64
+  * WebAssembly via Emscripten (bytecode interpreter only)
+diff --git a/racket/src/ChezScheme/c/number.c b/racket/src/ChezScheme/c/number.c
+index ede38cc626..e2bce0d2d3 100644
+--- a/racket/src/ChezScheme/c/number.c
++++ b/racket/src/ChezScheme/c/number.c
+@@ -1041,15 +1041,15 @@ floating-point operations
+ 
+ #ifdef IEEE_DOUBLE
+ /* exponent stored + 1024, hidden bit to left of decimal point */
+-#define bias 1023
+-#define bitstoright 52
+-#define m1mask 0xf
+-#ifdef WIN32
+-#define hidden_bit 0x10000000000000
+-#else
+-#define hidden_bit 0x10000000000000ULL
+-#endif
+-#ifdef LITTLE_ENDIAN_IEEE_DOUBLE
++# define bias 1023
++# define bitstoright 52
++# define m1mask 0xf
++# ifdef WIN32
++#  define hidden_bit 0x10000000000000
++# else
++#  define hidden_bit 0x10000000000000ULL
++# endif
++# ifdef LITTLE_ENDIAN_IEEE_DOUBLE
+ struct dblflt {
+     UINT m4: 16;
+     UINT m3: 16;
+@@ -1058,7 +1058,7 @@ struct dblflt {
+     UINT e: 11;
+     UINT sign: 1;
+ };
+-#else
++# else
+ struct dblflt {
+     UINT sign: 1;
+     UINT e: 11;
+@@ -1067,7 +1067,7 @@ struct dblflt {
+     UINT m3: 16;
+     UINT m4: 16;
+ };
+-#endif
++# endif
+ #endif
+ 
+ double S_random_double(U32 m1, U32 m2, U32 m3, U32 m4, double scale) {
+diff --git a/racket/src/ChezScheme/c/prim5.c b/racket/src/ChezScheme/c/prim5.c
+index 124d1e049c..82bbf8d687 100644
+--- a/racket/src/ChezScheme/c/prim5.c
++++ b/racket/src/ChezScheme/c/prim5.c
+@@ -23,6 +23,10 @@
+ #include <ctype.h>
+ #include <math.h>
+ 
++#if defined(__GNU__) /* Hurd */
++#include <sys/resource.h>
++#endif
++
+ /* locally defined functions */
+ static INT s_errno(void);
+ static IBOOL s_addr_in_heap(uptr x);
+@@ -58,7 +62,7 @@ static void s_showalloc(IBOOL show_dump, const char *outfn);
+ static ptr s_system(const char *s);
+ static ptr s_process(char *s, IBOOL stderrp);
+ static I32 s_chdir(const char *inpath);
+-#ifdef GETWD
++#if defined(GETWD) || defined(__GNU__) /* Hurd */
+ static char *s_getwd(void);
+ #endif
+ static ptr s_set_code_byte(ptr p, ptr n, ptr x);
+@@ -881,7 +885,18 @@ static ptr s_process(char *s, IBOOL stderrp) {
+         CLOSE(0); if (dup(tofds[0]) != 0) _exit(1);
+         CLOSE(1); if (dup(fromfds[1]) != 1) _exit(1);
+         CLOSE(2); if (dup(stderrp ? errfds[1] : 1) != 2) _exit(1);
++#ifndef __GNU__ /* Hurd */
+         {INT i; for (i = 3; i < NOFILE; i++) (void)CLOSE(i);}
++#else /* __GNU__ Hurd: no NOFILE */
++        {
++          INT i;
++          struct rlimit rlim;
++          getrlimit(RLIMIT_NOFILE, &rlim);
++          for (i = 3; i < rlim.rlim_cur; i++) {
++            (void)CLOSE(i);
++          }
++        }
++#endif /* __GNU__ Hurd */
+         execl("/bin/sh", "/bin/sh", "-c", s, NULL);
+         _exit(1) /* only if execl fails */;
+         /*NOTREACHED*/
+@@ -927,6 +942,22 @@ static I32 s_chdir(const char *inpath) {
+ static char *s_getwd() {
+   return GETWD(TO_VOIDP(&BVIT(S_bytevector(PATH_MAX), 0)));
+ }
++#elif defined(__GNU__) /* Hurd: no PATH_MAX */
++static char *s_getwd() {
++  char *path;
++  size_t len;
++  ptr bv;
++  path = getcwd(NULL, 0);
++  if (NULL == path) {
++    return NULL;
++  } else {
++    len = strlen(path);
++    bv = S_bytevector(len);
++    memcpy(TO_VOIDP(&BVIT(bv, 0)), path, len);
++    free(path);
++    return TO_VOIDP(&BVIT(bv, 0));
++  }
++}
+ #endif /* GETWD */
+ 
+ static ptr s_set_code_byte(ptr p, ptr n, ptr x) {
+@@ -1817,7 +1848,7 @@ void S_prim5_init(void) {
+     Sforeign_symbol("(cs)s_rational", (void *)S_rational);
+     Sforeign_symbol("(cs)sub", (void *)S_sub);
+     Sforeign_symbol("(cs)rem", (void *)S_rem);
+-#ifdef GETWD
++#if defined(GETWD) || defined(__GNU__) /* Hurd */
+     Sforeign_symbol("(cs)s_getwd", (void *)s_getwd);
+ #endif
+     Sforeign_symbol("(cs)s_chdir", (void *)s_chdir);
+diff --git a/racket/src/ChezScheme/c/scheme.c b/racket/src/ChezScheme/c/scheme.c
+index ed5564540b..0c40e3eaf0 100644
+--- a/racket/src/ChezScheme/c/scheme.c
++++ b/racket/src/ChezScheme/c/scheme.c
+@@ -458,6 +458,12 @@ static IBOOL next_path(char *path, const char *name, const char *ext, const char
+ static const char *path_last(const char *path);
+ static char *get_defaultheapdirs(void);
+ 
++#ifdef PATH_MAX
++# define BOOT_PATH_MAX PATH_MAX
++#else /* hack for Hurd: better to remove the restriction */
++# define BOOT_PATH_MAX 4096
++#endif
++
+ static const char *path_last(const char *p) {
+   const char *s;
+ #ifdef WIN32
+@@ -483,7 +489,7 @@ static const char *path_last(const char *p) {
+ 
+ static char *get_defaultheapdirs() {
+   char *result;
+-  wchar_t buf[PATH_MAX];
++  wchar_t buf[BOOT_PATH_MAX];
+   DWORD len = sizeof(buf);
+   if (ERROR_SUCCESS != RegGetValueW(HKEY_LOCAL_MACHINE, L"Software\\Chez Scheme\\csv" VERSION, L"HeapSearchPath", RRF_RT_REG_SZ, NULL, buf, &len))
+     return DEFAULT_HEAP_PATH;
+@@ -512,14 +518,14 @@ static char *get_defaultheapdirs() {
+  * leaving the full path with name affixed in path and *sp / *dsp pointing
+  * past the current entry.  it returns 1 on success and 0 if at the end of
+  * the search path.  path should be a pointer to an unoccupied buffer
+- * PATH_MAX characters long.  either or both of sp/dsp may be empty,
++ * BOOT_PATH_MAX characters long.  either or both of sp/dsp may be empty,
+  * but neither may be null, i.e., (char *)0. */
+ static IBOOL next_path(char *path, const char *name, const char *ext,
+                        const char **sp, const char **dsp) {
+   char *p;
+   const char *s, *t;
+ 
+-#define setp(c) if (p >= path + PATH_MAX) { fprintf(stderr, "search path entry too long\n"); S_abnormal_exit(); } else *p++ = (c)
++#define setp(c) if (p >= path + BOOT_PATH_MAX) { fprintf(stderr, "search path entry too long\n"); S_abnormal_exit(); } else *p++ = (c)
+   for (;;) {
+     s = *sp;
+     p = path;
+@@ -532,10 +538,10 @@ static IBOOL next_path(char *path, const char *name, const char *ext,
+           switch (*s) {
+ #ifdef WIN32
+             case 'x': {
+-              wchar_t exepath[PATH_MAX]; DWORD n;
++              wchar_t exepath[BOOT_PATH_MAX]; DWORD n;
+               s += 1;
+-              n = GetModuleFileNameW(NULL, exepath, PATH_MAX);
+-              if (n == 0 || (n == PATH_MAX && GetLastError() == ERROR_INSUFFICIENT_BUFFER)) {
++              n = GetModuleFileNameW(NULL, exepath, BOOT_PATH_MAX);
++              if (n == 0 || (n == BOOT_PATH_MAX && GetLastError() == ERROR_INSUFFICIENT_BUFFER)) {
+                 fprintf(stderr, "warning: executable path is too long; ignoring %%x\n");
+               } else {
+                 char *tstart;
+@@ -608,7 +614,7 @@ typedef struct {
+   iptr len; /* 0 => unknown */
+   iptr offset;
+   IBOOL need_check, close_after;
+-  char path[PATH_MAX];
++  char path[BOOT_PATH_MAX];
+ } boot_desc;
+ 
+ #define MAX_BOOT_FILES 10
+@@ -695,14 +701,14 @@ static void finish_dependencies_header(int fd, const char *path, int c) {
+ static IBOOL find_boot(const char *name, const char *ext, IBOOL direct_pathp,
+                        int fd,
+                        IBOOL errorp) {
+-  char pathbuf[PATH_MAX], buf[PATH_MAX];
++  char pathbuf[BOOT_PATH_MAX], buf[BOOT_PATH_MAX];
+   uptr n = 0;
+   INT c;
+   const char *path;
+   char *expandedpath;
+ 
+   if ((fd != -1) || direct_pathp || S_fixedpathp(name)) {
+-    if (strlen(name) >= PATH_MAX) {
++    if (strlen(name) >= BOOT_PATH_MAX) {
+       fprintf(stderr, "boot-file path is too long %s\n", name);
+       S_abnormal_exit();
+     }
+@@ -776,7 +782,7 @@ static IBOOL find_boot(const char *name, const char *ext, IBOOL direct_pathp,
+     if (boot_count == 0) {
+       for (;;) {
+        /* try to load heap or boot file this boot file requires */
+-        if (get_string(fd, buf, PATH_MAX, &c) != 0) {
++        if (get_string(fd, buf, BOOT_PATH_MAX, &c) != 0) {
+           fprintf(stderr, "unexpected end of file on %s\n", path);
+           CLOSE(fd);
+           S_abnormal_exit();
+@@ -796,7 +802,7 @@ static IBOOL find_boot(const char *name, const char *ext, IBOOL direct_pathp,
+           c = get_u8(fd);
+           for (sep = " "; ; sep = "or ") {
+             if (c == ')') break;
+-            (void) get_string(fd, buf, PATH_MAX, &c);
++            (void) get_string(fd, buf, BOOT_PATH_MAX, &c);
+             fprintf(stderr, "%s%s.boot ", sep, buf);
+           }
+           fprintf(stderr, "required by %s\n", path);
+@@ -1090,7 +1096,7 @@ extern void Sregister_boot_file_fd_region(const char *name,
+                                           int close_after) {
+   check_boot_file_state("Sregister_boot_file_fd");
+ 
+-  if (strlen(name) >= PATH_MAX) {
++  if (strlen(name) >= BOOT_PATH_MAX) {
+     fprintf(stderr, "boot-file path is too long %s\n", name);
+     S_abnormal_exit();
+   }
+@@ -1141,14 +1147,14 @@ extern void Sbuild_heap(const char *kernel, void (*custom_init)(void)) {
+     }
+ 
+     name = path_last(kernel);
+-    if (strlen(name) >= PATH_MAX) {
++    if (strlen(name) >= BOOT_PATH_MAX) {
+       fprintf(stderr, "executable name too long: %s\n", name);
+       S_abnormal_exit();
+     }
+ 
+ #ifdef WIN32
+     { /* strip off trailing .exe, if any */
+-      static char buf[PATH_MAX];
++      static char buf[BOOT_PATH_MAX];
+       iptr n;
+ 
+       n = strlen(name) - 4;
+diff --git a/racket/src/ChezScheme/c/version.h b/racket/src/ChezScheme/c/version.h
+index a79d12621b..61751a9fad 100644
+--- a/racket/src/ChezScheme/c/version.h
++++ b/racket/src/ChezScheme/c/version.h
+@@ -80,7 +80,7 @@ FORCEINLINE void store_unaligned_uptr(uptr *addr, uptr val) {
+ /*****************************************/
+ /* Operating systems                     */
+ 
+-#if defined(__linux__)
++#if defined(__linux__) || defined(__GNU__) /* Hurd */
+ #define NOBLOCK O_NONBLOCK
+ #define LOAD_SHARED_OBJECT
+ #define USE_MMAP
+@@ -91,7 +91,10 @@ FORCEINLINE void store_unaligned_uptr(uptr *addr, uptr val) {
+ #define GETPAGESIZE() getpagesize()
+ typedef char *memcpy_t;
+ #define MAKE_NAN(x) { x = 0.0; x = x / x; }
+-#define GETWD(x) getcwd((x),PATH_MAX)
++#ifndef __GNU__ /* Hurd: no PATH_MAX */
++/* n.b. don't test PATH_MAX directly: we have not yet included <limits.h>  */
++# define GETWD(x) getcwd((x),PATH_MAX)
++#endif
+ typedef int tputsputcchar;
+ #ifndef __ANDROID__
+ # define LOCKF
+diff --git a/racket/src/ChezScheme/configure b/racket/src/ChezScheme/configure
+index f64b639c3a..efdb6029cb 100755
+--- a/racket/src/ChezScheme/configure
++++ b/racket/src/ChezScheme/configure
+@@ -102,6 +102,11 @@ case "${CONFIG_UNAME}" in
+     installprefix=/usr
+     installmansuffix=share/man
+     ;;
++  GNU)
++    unixsuffix=gnu # the Hurd
++    installprefix=/usr
++    installmansuffix=share/man
++    ;;
+   QNX)
+     if uname -a | egrep 'x86' > /dev/null 2>&1 ; then
+       m32=i3qnx
+@@ -591,7 +596,7 @@ fi
+ 
+ # Infer flags needed for threads:
+ case "${flagsm}" in
+-  *le|*fb|*ob|*nb)
++  *le|*gnu|*fb|*ob|*nb)
+       threadFlags="-D_REENTRANT -pthread"
+       threadLibs="-lpthread"
+       ;;
+@@ -627,7 +632,7 @@ if [ "$cflagsset" = "no" ] ; then
+     a6*)
+         CFLAGS="-m64 ${optFlags}"
+         ;;
+-    i3le)
++    i3le) # intentionally not including i3gnu, which may not support sse2
+         CFLAGS="-m32 -msse2 -mfpmath=sse ${optFlags}"
+         ;;
+     i3nt)
+@@ -688,7 +693,7 @@ fi
+ # Add automatic linking flags, unless suppressed by --disable-auto-flags
+ if [ "$addflags" = "yes" ] ; then
+   case "${flagsm}" in
+-    *le)
++    *le|*gnu)
+         LDFLAGS="${LDFLAGS} -rdynamic"
+         ;;
+     *fb|*nb)
+@@ -702,7 +707,7 @@ if [ "$addflags" = "yes" ] ; then
+   esac
+ 
+   case "${flagsm}" in
+-    *le)
++    *le|*gnu)
+         LIBS="${LIBS} -lm -ldl ${ncursesLib} -lrt"
+         ;;
+     *fb|*ob)
+@@ -749,7 +754,7 @@ exeSuffix=
+ 
+ # compile flags for c/Mf-unix and mats/Mf-unix
+ case "${flagsmuni}" in
+-    *le)
++    *le|*gnu)
+         mdcflags="-fPIC -shared"
+         ;;
+     *fb|*ob)
+@@ -781,7 +786,7 @@ case "${flagsmuni}" in
+     i3le)
+         mdldflags="-melf_i386"
+         ;;
+-    *le)
++    *le|*gnu)
+         ;;
+     i3nb)
+         mdldflags="-m elf_i386"
+diff --git a/racket/src/ChezScheme/s/cmacros.ss b/racket/src/ChezScheme/s/cmacros.ss
+index ff2b09217b..2e79a4d8de 100644
+--- a/racket/src/ChezScheme/s/cmacros.ss
++++ b/racket/src/ChezScheme/s/cmacros.ss
+@@ -385,6 +385,7 @@
+   i3fb      ti3fb
+   i3ob      ti3ob
+   i3osx     ti3osx
++  i3gnu     ti3gnu
+   a6le      ta6le
+   a6osx     ta6osx
+   a6ob      ta6ob
+diff --git a/racket/src/cs/c/configure b/racket/src/cs/c/configure
+index 454d79e11a..dab545c0b4 100755
+--- a/racket/src/cs/c/configure
++++ b/racket/src/cs/c/configure
+@@ -4449,8 +4449,15 @@ case "$host_os" in
+     ;;
+   irix*)
+     ;;
+-  linux*)
+-    MACH_OS=le
++  linux*|gnu*)
++    case "$host_os" in
++      *linux*)
++        MACH_OS=le
++        ;;
++      *)
++        MACH_OS=gnu # Hurd
++        ;;
++    esac
+     case "$host_os" in
+       *linux-android*)
+         ;;
+@@ -4730,6 +4737,9 @@ if test "${build_os}_${build_cpu}" != "${host_os}_${host_cpu}" ; then
+     linux*)
+       BUILD_OS=le
+       ;;
++    gnu*) # Hurd: must come after linux*
++      BUILD_OS=gnu
++      ;;
+     *mingw*)
+       BUILD_OS=nt
+       ;;
+diff --git a/racket/src/cs/c/configure.ac b/racket/src/cs/c/configure.ac
+index 5bce979c92..43e7307b1b 100644
+--- a/racket/src/cs/c/configure.ac
++++ b/racket/src/cs/c/configure.ac
+@@ -272,8 +272,15 @@ case "$host_os" in
+     ;;
+   irix*)
+     ;;
+-  linux*)
+-    MACH_OS=le
++  linux*|gnu*)
++    case "$host_os" in
++      linux*)
++        MACH_OS=le
++        ;;
++      *)
++        MACH_OS=gnu # Hurd
++        ;;
++    esac
+     case "$host_os" in
+       *linux-android*)
+         ;;
+@@ -466,6 +473,9 @@ if test "${build_os}_${build_cpu}" != "${host_os}_${host_cpu}" ; then
+     linux*)
+       BUILD_OS=le
+       ;;
++    gnu*) # Hurd - must come after linux*
++      BUILD_OS=gnu
++      ;;
+     *mingw*)
+       BUILD_OS=nt
+       ;;
+diff --git a/racket/src/cs/rumble/system.ss b/racket/src/cs/rumble/system.ss
+index 2319cbe7a5..773eb79cf3 100644
+--- a/racket/src/cs/rumble/system.ss
++++ b/racket/src/cs/rumble/system.ss
+@@ -48,6 +48,8 @@
+            arm32le tarm32le arm64le tarm64le
+            ppc32le tppc32le)
+      'linux]
++    [(i3gnu ti3gnu)
++     'gnu-hurd]
+     [(a6fb ta6fb i3fb ti3fb
+            arm32fb tarm32fb arm64fb tarm64fb
+            ppc32fb tppc32fb)
+@@ -85,6 +87,7 @@
+             i3nb ti3nb
+             i3fb ti3fb
+             i3s2 ti3s2
++            i3gnu ti3gnu
+             i3qnx)
+      'i386]
+     [(arm32le tarm32le
+-- 
+2.32.0
+
+
+From 8653294b771c741d320aba31e692b4f0ed0c702f Mon Sep 17 00:00:00 2001
+From: Philip McGrath <philip@philipmcgrath.com>
+Date: Thu, 4 Aug 2022 20:18:09 -0400
+Subject: [PATCH 2/3] BC: Fix build on GNU/Hurd
+
+(cherry picked from commit 5c05496afd6159c2f9cd52e7f23389fdc6b55f43)
+---
+ racket/src/bc/configure    |  2 +-
+ racket/src/bc/configure.ac |  2 +-
+ racket/src/bc/sconfig.h    | 14 +++++++++-----
+ 3 files changed, 11 insertions(+), 7 deletions(-)
+
+diff --git a/racket/src/bc/configure b/racket/src/bc/configure
+index 4ddb607b37..4ee346014d 100755
+--- a/racket/src/bc/configure
++++ b/racket/src/bc/configure
+@@ -5018,7 +5018,7 @@ case "$host_os" in
+       X_PRE_LIBS=""
+     fi
+     ;;
+-  linux*)
++  linux*,gnu*)
+     LIBS="$LIBS -ldl -lm -lrt -rdynamic"
+     DYN_CFLAGS="-fPIC"
+     curses_portable_link="/usr/lib/${host_cpu}-${host_os}/libncurses.a /usr/lib/${host_cpu}-${host_os}/libtermcap.a"
+diff --git a/racket/src/bc/configure.ac b/racket/src/bc/configure.ac
+index deef8f3077..866851236e 100644
+--- a/racket/src/bc/configure.ac
++++ b/racket/src/bc/configure.ac
+@@ -557,7 +557,7 @@ case "$host_os" in
+       X_PRE_LIBS=""
+     fi
+     ;;
+-  linux*)
++  linux*,gnu*)
+     LIBS="$LIBS -ldl -lm -lrt -rdynamic"
+     DYN_CFLAGS="-fPIC"
+     curses_portable_link="/usr/lib/${host_cpu}-${host_os}/libncurses.a /usr/lib/${host_cpu}-${host_os}/libtermcap.a"
+diff --git a/racket/src/bc/sconfig.h b/racket/src/bc/sconfig.h
+index 01ecb48158..8468942fcd 100644
+--- a/racket/src/bc/sconfig.h
++++ b/racket/src/bc/sconfig.h
+@@ -79,12 +79,14 @@
+ 
+ #endif
+ 
+-  /************** Linux with gcc ****************/
++  /************** Linux (or Hurd) with gcc ****************/
+ 
+-#if defined(__linux__)
++#if defined(__linux__) || defined(__GNU__)
+ 
+ # ifdef __ANDROID__
+ #  define SCHEME_OS "android"
++# elif defined(__GNU__)
++#  define SCHEME_OS "gnu-hurd"
+ # else
+ #  define SCHEME_OS "linux"
+ # endif
+@@ -146,13 +148,15 @@
+ # define USE_IEEE_FP_PREDS
+ # define USE_EXPLICT_FP_FORM_CHECK
+ 
+-# define LINUX_FIND_STACK_BASE
++# define LINUX_FIND_STACK_BASE /* also ok for Hurd */
+ 
+ # define FLAGS_ALREADY_SET
+ 
+ #if defined(__i386__)
+-# define MZ_USE_JIT_I386
+-# define MZ_JIT_USE_MPROTECT
++# ifndef __GNU__ /* Hurd */
++#  define MZ_USE_JIT_I386
++#  define MZ_JIT_USE_MPROTECT
++# endif
+ # ifndef MZ_NO_UNWIND_SUPPORT
+ #  define MZ_USE_DWARF_LIBUNWIND
+ # endif
+-- 
+2.32.0
+
+
+From 1b0cd08557f58506c96f0ddd855bd9051a45a2f1 Mon Sep 17 00:00:00 2001
+From: Philip McGrath <philip@philipmcgrath.com>
+Date: Sat, 6 Aug 2022 22:48:40 -0400
+Subject: [PATCH 3/3] BC: repair configure script
+
+Hopefully this will fix the DrDr failures caused by 5c05496.
+
+Related to https://github.com/racket/racket/pull/4384
+
+(cherry picked from commit c3dd01055ed7589a18136904510fe4db557d6e77)
+---
+ racket/src/bc/configure    | 2 +-
+ racket/src/bc/configure.ac | 2 +-
+ 2 files changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/racket/src/bc/configure b/racket/src/bc/configure
+index 4ee346014d..b1c5175b84 100755
+--- a/racket/src/bc/configure
++++ b/racket/src/bc/configure
+@@ -5018,7 +5018,7 @@ case "$host_os" in
+       X_PRE_LIBS=""
+     fi
+     ;;
+-  linux*,gnu*)
++  linux*|gnu*)
+     LIBS="$LIBS -ldl -lm -lrt -rdynamic"
+     DYN_CFLAGS="-fPIC"
+     curses_portable_link="/usr/lib/${host_cpu}-${host_os}/libncurses.a /usr/lib/${host_cpu}-${host_os}/libtermcap.a"
+diff --git a/racket/src/bc/configure.ac b/racket/src/bc/configure.ac
+index 866851236e..ecc3b0b579 100644
+--- a/racket/src/bc/configure.ac
++++ b/racket/src/bc/configure.ac
+@@ -557,7 +557,7 @@ case "$host_os" in
+       X_PRE_LIBS=""
+     fi
+     ;;
+-  linux*,gnu*)
++  linux*|gnu*)
+     LIBS="$LIBS -ldl -lm -lrt -rdynamic"
+     DYN_CFLAGS="-fPIC"
+     curses_portable_link="/usr/lib/${host_cpu}-${host_os}/libncurses.a /usr/lib/${host_cpu}-${host_os}/libtermcap.a"
+-- 
+2.32.0
+
diff --git a/gnu/packages/patches/racket-chez-scheme-bin-sh.patch b/gnu/packages/patches/racket-chez-scheme-bin-sh.patch
index 65cf2f99f3..331b4f244b 100644
--- a/gnu/packages/patches/racket-chez-scheme-bin-sh.patch
+++ b/gnu/packages/patches/racket-chez-scheme-bin-sh.patch
@@ -1,4 +1,4 @@
-From e982b6687494bf071386c67be74e57a29cf4ce00 Mon Sep 17 00:00:00 2001
+From f86370295c5bb14d4bb93d0ccfa37a2b79f19f25 Mon Sep 17 00:00:00 2001
 From: Philip McGrath <philip@philipmcgrath.com>
 Date: Wed, 24 Aug 2022 19:55:14 -0400
 Subject: [PATCH] Chez Scheme: patch s_process for "/bin/sh" on Guix
@@ -24,12 +24,12 @@ on `system` from the C library.
  1 file changed, 20 insertions(+), 1 deletion(-)
 
 diff --git a/racket/src/ChezScheme/c/prim5.c b/racket/src/ChezScheme/c/prim5.c
-index f5e3e345be..922421ca75 100644
+index 82bbf8d687..be8f603447 100644
 --- a/racket/src/ChezScheme/c/prim5.c
 +++ b/racket/src/ChezScheme/c/prim5.c
-@@ -22,6 +22,12 @@
- #include <limits.h>
- #include <ctype.h>
+@@ -27,6 +27,12 @@
+ #include <sys/resource.h>
+ #endif
  
 +/* BEGIN PATCH for Guix */
 +#ifndef WIN32
@@ -38,9 +38,9 @@ index f5e3e345be..922421ca75 100644
 +/* END PATCH for Guix */
 +
  /* locally defined functions */
- static INT s_errno PROTO((void));
- static IBOOL s_addr_in_heap PROTO((uptr x));
-@@ -856,6 +862,17 @@ static ptr s_process(s, stderrp) char *s; IBOOL stderrp; {
+ static INT s_errno(void);
+ static IBOOL s_addr_in_heap(uptr x);
+@@ -861,6 +867,17 @@ static ptr s_process(char *s, IBOOL stderrp) {
  
      INT tofds[2], fromfds[2], errfds[2];
      struct sigaction act, oint_act;
@@ -58,10 +58,10 @@ index f5e3e345be..922421ca75 100644
  
      if (pipe(tofds)) S_error("process","cannot open pipes");
      if (pipe(fromfds)) {
-@@ -881,7 +898,9 @@ static ptr s_process(s, stderrp) char *s; IBOOL stderrp; {
-         CLOSE(1); if (dup(fromfds[1]) != 1) _exit(1);
-         CLOSE(2); if (dup(stderrp ? errfds[1] : 1) != 2) _exit(1);
-         {INT i; for (i = 3; i < NOFILE; i++) (void)CLOSE(i);}
+@@ -897,7 +914,9 @@ static ptr s_process(char *s, IBOOL stderrp) {
+           }
+         }
+ #endif /* __GNU__ Hurd */
 -        execl("/bin/sh", "/bin/sh", "-c", s, NULL);
 +        /* BEGIN PATCH for Guix */
 +        execl(guix_sh, guix_sh, "-c", s, NULL);
@@ -70,7 +70,7 @@ index f5e3e345be..922421ca75 100644
          /*NOTREACHED*/
      } else {
 
-base-commit: 9d228d16fb99c274c964e5bef93e97333888769f
+base-commit: 87eee6e2adb8c6bc11e60619c706fa6295096085
 -- 
 2.32.0
 
diff --git a/gnu/packages/racket.scm b/gnu/packages/racket.scm
index 70df5482fb..349cf38e07 100644
--- a/gnu/packages/racket.scm
+++ b/gnu/packages/racket.scm
@@ -53,7 +53,7 @@
   #:use-module (gnu packages xorg)
   #:use-module ((guix licenses) #:prefix license:))
 
-;; Commentary:
+;; COMMENTARY:
 ;;
 ;; Anatomy of Racket:
 ;; ------------------
@@ -72,14 +72,16 @@
 ;;             ├── bc/
 ;;             ├── cs/
 ;;             ├── ChezScheme/
+;;             ├── zuo/
 ;;             └── ...
 ;;
 ;; The 'racket/src/' directory contains the source of the runtime system, core
 ;; compiler, and primitives for the major Racket implementations: this layer
-;; is called the ``Racket VM''. It is basically a normal autotools
-;; project. (Even when Racket VM implementations use components implemented in
-;; Racket, they are compiled in special modes to produce VM primitives.)
-;; (There are or have been experimental Racket VM implementations elsewhere,
+;; is called the ``Racket VM''.  It is basically a normal Autoconf project,
+;; except that the makefiles just run Zuo to do the real work. (Even when
+;; Racket VM implementations use components implemented in Racket, they are
+;; compiled in special modes to produce VM primitives.) (There are or have
+;; been experimental Racket VM implementations elsewhere,
 ;; e.g. <https://github.com/pycket/pycket>.)
 ;;
 ;; The 'racket/collects/' directory contains ``built in'' Racket libraries
@@ -100,10 +102,10 @@
 ;;
 ;; The top-level 'Makefile' is more like a directory of scripts: it has
 ;; convienience targets for developing Racket, and it cooperates with the
-;; 'distro-build' package to assemble custom Racket distributions. It is not
-;; part of Racket source distributions: the root of a source distribution is
-;; basically 'racket/src' with some extra package sources and configuration
-;; added.
+;; 'distro-build' package to assemble custom Racket distributions. (Again,
+;; the makefile just delegates to Zuo.) It is not part of Racket source
+;; distributions: the root of a source distribution is basically 'racket/src'
+;; with some extra package sources and configuration added.
 ;;
 ;; A ''minimal Racket'' installation includes two packages: 'base', which is a
 ;; sort of bridge between the current ``built-in'' collections and the package
@@ -129,12 +131,12 @@
 ;; output. The function 'racket-vm-for-system' returns the recomended Racket
 ;; VM package for a given system.
 ;;
-;; The file 'racket.scm' builds on these packages to define 'racket-minimal'
-;; and 'racket' packages. These use Racket's support for ``layered
-;; installations'', which allow an immutable base layer to be extended with
-;; additional packages. They use the layer configuration directly provide
-;; ready-to-install FHS-like trees, rather than relying on the built in
-;; ``Unix-style install'' mechanism.
+;; We then define the packages 'racket-minimal' and
+;; 'racket'. These use Racket's support for ``layered installations'', which
+;; allow an immutable base layer to be extended with additional packages.
+;; They use the layer configuration directly provide ready-to-install FHS-like
+;; trees, rather than relying on the built in ``Unix-style install''
+;; mechanism.
 ;;
 ;; Bootstrapping Racket:
 ;; ---------------------
@@ -177,16 +179,18 @@
 ;; However, other Racket subsystems implemented in Racket for Racket CS
 ;; use older C implementations for Racket BC, whereas the reader, expander,
 ;; and module system were completely replaced with the Racket implementation
-;; as of Racket 7.0.
+;; as of Racket 7.0. See also <https://racket.discourse.group/t/951/4>.
 ;;
 ;; For Racket BC, the compiled "linklet" s-expressions (primitive modules)
 ;; are embeded in C as a static string constant. Eventually, they are further
 ;; compiled by the C-implemented Racket BC bytecode and JIT compilers.
-;; (On platforms where Racket BC's JIT is not supported, yet another compiler
-;; instead compiles the linklets to C code, but this is not a bootstrapping
-;; issue.)
 ;;
-;; Code:
+;; Zuo is notably *not* a problem for bootstrapping. The implementation is a
+;; single hand-written C file designed to build with just `cc -o zuo zuo.c`,
+;; even with very old or limited compilers. (We use the Autoconf support for
+;; convienience.)
+;;
+;; CODE:
 
 (define* (racket-vm-for-system #:optional
                                (system (or (%current-target-system)
@@ -199,7 +203,7 @@ otherwise."
       racket-vm-cs
       racket-vm-bc))
 
-(define %racket-version "8.5") ; Remember to update chez-scheme-for-racket!
+(define %racket-version "8.6") ; Remember to update chez-scheme-for-racket!
 (define %zuo-version "1.0") ; defined in racket/src/zuo/zuo.c
 (define %racket-commit
   (string-append "v" %racket-version))
@@ -210,10 +214,15 @@ otherwise."
           (url "https://github.com/racket/racket")
           (commit %racket-commit)))
     (sha256
-     (base32 "0f9zyhdvbh4xsndrqjzl85j5ziz0rmqi676g9s1lw3h3skq2636h"))
+     (base32 "1lw6h70dk8zqpl96zz0hmhn8vjcc0c7gw4prkfz2wid5bkq4mhg4"))
     (file-name (git-file-name "racket" %racket-version))
-    (patches (search-patches "racket-chez-scheme-bin-sh.patch"
-                             "racket-rktio-bin-sh.patch"))
+    (patches (search-patches "racket-backport-8.6-cross-install.patch"
+                             "racket-backport-8.6-docindex-write.patch"
+                             "racket-backport-8.6-hurd.patch"
+                             "racket-backport-8.6-zuo.patch"
+                             "racket-chez-scheme-bin-sh.patch"
+                             "racket-rktio-bin-sh.patch"
+                             "racket-zuo-bin-sh.patch"))
     (modules '((guix build utils)))
     (snippet
      #~(begin
@@ -240,21 +249,10 @@ otherwise."
       (name "zuo")
       (version (string-append %zuo-version
                               "-racket"
-                              "8.6"
+                              %racket-version
                               (if revision "-guix" "")
                               (or revision "")))
-      (source
-       (origin
-         (inherit %racket-origin)
-         (uri (git-reference
-               (url "https://github.com/racket/racket")
-               (commit "v8.6")))
-         (sha256
-          (base32 "1yi36nr7zrdwrnvpmliirxxjz4pyfyhkar6yvk3rapvmg4q2vmnk"))
-         (patches (append (origin-patches %racket-origin)
-                          (search-patches "racket-backport-8.6-zuo.patch"
-                                          "racket-zuo-bin-sh.patch")))
-         (file-name (git-file-name "racket" "8.6"))))
+      (source %racket-origin)
       (outputs '("out" "debug"))
       (build-system gnu-build-system)
       (arguments
@@ -314,7 +312,8 @@ One of the early layers implements macros.")
      (source %racket-origin)
      (inputs (list ncurses ;; <- common to all variants (for #%terminal)
                    libffi)) ;; <- only for BC variants
-     (native-inputs (list libtool)) ;; <- only for BC variants
+     (native-inputs (list zuo ;; <- for all variants
+                          libtool)) ;; <- only for BC variants
      (outputs '("out" "debug"))
      (build-system gnu-build-system)
      (arguments
@@ -322,6 +321,10 @@ One of the early layers implements macros.")
        #:configure-flags
        #~(cons "--enable-cgcdefault"
                #$racket-vm-common-configure-flags)
+       #:make-flags
+       #~(list (string-append "ZUO="
+                              #+(this-package-native-input "zuo")
+                              "/bin/zuo"))
        ;; Tests are in packages like racket-test-core and
        ;; main-distribution-test that aren't part of the main
        ;; distribution.
@@ -681,25 +684,25 @@ DrRacket IDE, are not included.")
        "contract-profile" (base32 "1xm2z8g0dpv5d9h2sg680vx1a8ix9gbsdpxxb8qv1w7akp73paj3")
        '(("contract-profile" ".")))
       (simple-racket-origin
-       "data" (base32 "10iabgrk9alaggvksnyb0hdq7f1p30pq6pq2bcakvhzpxwiv1f55")
+       "data" (base32 "08sj4m0g0cp7gwb0nq90m770f0c21b7ydif7nljc8rxmcdprfisc")
        '("data" "data-doc" "data-enumerate-lib" "data-lib"))
       (simple-racket-origin
        "datalog" (base32 "0nf6cy4djpyhfvgpa6yn72apbz9s83gp0qg95pzjd0az4v6qwq1s")
        '(("datalog" ".")))
       (simple-racket-origin
-       "db" (base32 "1n02ja0yj3mjjhmz0yv04yfhyvrsznbljn8bjviyfxnm4xf9rcc5")
+       "db" (base32 "0jzsbfcdm3xj0g8xxw3ky2swrhiqqsq2aqa3r08m641dc981dmjq")
        '("db" "db-doc" "db-lib"))
       (simple-racket-origin
-       "deinprogramm" (base32 "0g8flr1qg3bcyhdinqhs4w7dyisaqyailbxrjgd2a7zlqmdyicfr")
+       "deinprogramm" (base32 "16ncs3ms3mmdavbk0mkhm2qi62vyyif9cch3sn1y64pij489x34v")
        '("deinprogramm" "deinprogramm-signature"))
       (simple-racket-origin
        "distributed-places" (base32 "1dajpkj9balqcpv6cdk9hwjz592h1vq8rrx5vncariiac4vbdpa0")
        '("distributed-places" "distributed-places-doc" "distributed-places-lib"))
       (simple-racket-origin
-       "draw" (base32 "1fpk85rs2crd63bxnmwj2pysisd62pxcqaip01si67dv1ri8ff92")
+       "draw" (base32 "00rq5y4ba6z1d6jh76kl8rwpxrlqqp81a875zyhk3k81i42635sm")
        '("draw" "draw-doc" "draw-lib"))
       (simple-racket-origin
-       "drracket" (base32 "0dipnz92c63zxys9z1kl5215rm7arc35g9r8bs8ivp96p75mljnz")
+       "drracket" (base32 "05d7wssi0ry13alb5hl3llpsg30dd0jhyfv5nb1nmg189fn42q62")
        '("drracket"
          "drracket-plugin-lib"
          "drracket-tool"
@@ -716,7 +719,7 @@ DrRacket IDE, are not included.")
        "eopl" (base32 "1fmiixj6rxsgzwvgva8lvrvv0gl49v2405mp3s0i7ipis5c4n27s")
        '(("eopl" ".")))
       (simple-racket-origin
-       "errortrace" (base32 "14m7rhaxngj36070iw15am434hm438pfgmwjfsiqhsglz4pcxhip")
+       "errortrace" (base32 "0r5630bb2d6hk0fbi95fmyfja54nnwdfcj2zjba124pp6xkjyavx")
        '("errortrace" "errortrace-doc" "errortrace-lib"))
       (simple-racket-origin
        "expeditor" (base32 "0mjfwb4wzwsg5xj3k6cmik0va432n56rp5h7rxx1c2yy3prh1j7q")
@@ -733,13 +736,13 @@ DrRacket IDE, are not included.")
        "games" (base32 "0kpn3izlx1ccd0pj0dnvmnrhny51b85xy418a7psj70lz8j8415d")
        '(("games" ".")))
       (simple-racket-origin
-       "gui" (base32 "0r3ck4gxdhnzr1a1fi0f1i7gwfip7akq10qgcxza66pp57hnl0wx")
+       "gui" (base32 "18pcnx3wi8f32i2frm8bn9pi08n4y3c5jgqs4gy21w6f84dv401w")
        '("gui" "gui-doc" "gui-lib" "tex-table"))
       (simple-racket-origin
        "gui-pkg-manager" (base32 "1ji9448d723nklqvycwdswj0ni28sabrncag14f9mx47did5myb5")
        '("gui-pkg-manager-lib"))
       (simple-racket-origin
-       "htdp" (base32 "19xqixrqbwdxph17w9jga19008j88harb5wgml4hpqj3x0apx9g3")
+       "htdp" (base32 "173xy6ks55npvwn6cykjs41s9qfb70hc2gfjiqvw91hdsbjykwir")
        '("htdp" "htdp-doc" "htdp-lib"))
       (simple-racket-origin
        "html" (base32 "18n1jnjgzfknc8nv8dppi85nb8q08gqdwkg6hfjk08x0p00anx2x")
@@ -763,7 +766,7 @@ DrRacket IDE, are not included.")
        "make" (base32 "10852fj30bz5r46c3d99s37fkgy5yh44gb01j29sf3kxnhi0g2sa")
        '(("make" ".")))
       (simple-racket-origin
-       "math" (base32 "02sqbnvxvmvslk33b44fx4v93zafcvhva0cx8z21jqbl5wp217ac")
+       "math" (base32 "00ld38in5jfshs1q4zf07w84cyv4yjr40kmw30pyd5wqgs2zq9ai")
        '("math" "math-doc" "math-lib"))
       (simple-racket-origin
        "mysterx" (base32 "11p9jzrafw0hizhl0cs4sxx7rv281185q8hryic2rpk0kzjdyr48")
@@ -798,16 +801,16 @@ DrRacket IDE, are not included.")
           (git-file-name "stamourv-optimization-coach" %racket-version)))
        '(("optimization-coach" ".")))
       (simple-racket-origin
-       "option-contract" (base32 "026b7n5l0c3024nymshz8zp1yhn493rdzgpflzfd52hj7awafqhk")
+       "option-contract" (base32 "07cncg9pi15cm19k7rzv54vx83wq7y42i2m6bgzaqja1h8vnj2ww")
        '("option-contract" "option-contract-doc" "option-contract-lib"))
       (simple-racket-origin
-       "parser-tools" (base32 "08pvz4zramirzm3j64hbhjm0mmh5zfy37iv4s3vmq0rj49cr8fl3")
+       "parser-tools" (base32 "04ycihliikh0c47ivp09gayxiql9d9wpl216czic19cj6f7rmcnj")
        '("parser-tools" "parser-tools-doc" "parser-tools-lib"))
       (simple-racket-origin
        "pconvert" (base32 "00czi0p399mmyrvxyrs5kniizpkqfxyz2ncxqi2jy79a7wk79pb1")
        '("pconvert-lib"))
       (simple-racket-origin
-       "pict" (base32 "0v7a3l77swsbh80mnb9rakdwgw7s66ji0mall7qcqfwyg1b4zmlv")
+       "pict" (base32 "1n0v7kynkiin1v8igs9m8k8vfwjn5cswanhq2imp1pxzjvdyq6sx")
        '("pict" "pict-doc" "pict-lib"))
       (simple-racket-origin
        "pict-snip" (base32 "081nwiy4a0n4f7xws16hqbhf0j3kz5alizndi3nnyr3chm4kng6x")
@@ -861,7 +864,7 @@ DrRacket IDE, are not included.")
        "racklog" (base32 "0fbq0fpfb3l6h7h772dvkmlzlk2dnq5f8296xx1qxhhwypibqzr9")
        '(("racklog" ".")))
       (simple-racket-origin
-       "rackunit" (base32 "0vfwcddzrgrdv5awjka7m0jzqhqvfc5wlkih83a670y96496a83n")
+       "rackunit" (base32 "1gpz9sgnm8hrc0cb3rii0wzbcwp9mgy5k1amnxidy7gyzl7prn81")
        '("rackunit"
          "rackunit-doc"
          "rackunit-gui"
@@ -874,10 +877,10 @@ DrRacket IDE, are not included.")
        "readline" (base32 "13kbcn2wchv82d709mw3r8n37bk8iwq0y4kpvm9dbzx0w2pxkfwn")
        '("readline" "readline-doc" "readline-lib"))
       (simple-racket-origin
-       "realm" (base32 "0hxcgla08iack54j8v40fj51811chpy66ym2zq76zb52c7kzn0hi")
+       "realm" (base32 "0rlvwyd6rpyl0zda4a5p8dp346fvqzc8555dgfnrhliymkxb6x4g")
        '(("realm" ".")))
       (simple-racket-origin
-       "redex" (base32 "18rn8ddsqh1s7hdlb2cb9wxln63bz0wysjssaf9v92r712xnnv8i")
+       "redex" (base32 "06dhyqmin0qdm6b6sdvgzpy3pa4svlw42ld9k2h1dxcr852czil7")
        '("redex"
          "redex-benchmark"
          "redex-doc"
@@ -892,7 +895,7 @@ DrRacket IDE, are not included.")
        "scheme-lib" (base32 "0pcf0y8rp4qyjhaz5ww5sr5diq0wpcdfrrnask7zapyklzx1jx8x")
        '(("scheme-lib" ".")))
       (simple-racket-origin
-       "scribble" (base32 "0fbb7xgz95y90247hfc1a19v7ry8m6blvv4y8irdgzhjvik70zb3")
+       "scribble" (base32 "0a11kvcnzp04mp4xxq68rkl09jv00hv81k2nmwkmwpfx9b2acvd3")
        '("scribble"
          "scribble-doc"
          "scribble-html-lib"
@@ -924,7 +927,7 @@ DrRacket IDE, are not included.")
        "snip" (base32 "01r9wc5xr3q3n4yyif6j0a37rgdzmpslxn05k13ksik73b3wj6hj")
        '("snip" "snip-lib"))
       (simple-racket-origin
-       "typed-racket" (base32 "0z6bagp6qiw0i3slhvq035y5hqgq664xw3bdlvdayad0bgbg0mdc")
+       "typed-racket" (base32 "03wsz647fi58brbg33fw1xavp100gzfvngdy8bk7bdc0jfg8a18l")
        '("source-syntax"
          "typed-racket"
          "typed-racket-compatibility"
@@ -935,13 +938,13 @@ DrRacket IDE, are not included.")
        "srfi" (base32 "0aqbcdv2dfc2xnk0h6zfi56p7bpwqji8s88qds3d03hhh9k28gvn")
        '("srfi" "srfi-doc" "srfi-lib" "srfi-lite-lib"))
       (simple-racket-origin
-       "string-constants" (base32 "0b1ji31pv6bjb0a2bh9sqp5abvf91gn2rai8r4c4nkar1fzfwfac")
+       "string-constants" (base32 "1kg3vxq2hcd0vl76brgpzdwbrb65a4nrrkc6hj4az5lfbbdvqz47")
        '("string-constants" "string-constants-doc" "string-constants-lib"))
       (simple-racket-origin
-       "swindle" (base32 "164gdsphjzdl2vv7zxz7dfk9jwax8njpmim6sidm8qz8a8589y67")
+       "swindle" (base32 "03n9ymjhrw45h7hxkw4nq8nidnvs9mfzb4228s2cjfaqbgqxvsyb")
        '(("swindle" ".")))
       (simple-racket-origin
-       "syntax-color" (base32 "17lb2403ymz6sflw4vs3gsh2y7kgsf0gn8sncsxjhi16rpj3a9vm")
+       "syntax-color" (base32 "02dcd4yvdnw35m3srvfd43csxffxw3j4rk6zi379b8dsvbbrjyq1")
        '("syntax-color" "syntax-color-doc" "syntax-color-lib"))
       (simple-racket-origin
        "trace" (base32 "070ihla5j796hdarn5wxdwn4xj0xnkm50shgh49jy994mribvhia")
@@ -950,7 +953,7 @@ DrRacket IDE, are not included.")
        "unix-socket" (base32 "02dfwas5ynbpyz74w9kwb4wgb37y5wys7svrlmir8k0n9ph9vq0y")
        '("unix-socket" "unix-socket-doc" "unix-socket-lib"))
       (simple-racket-origin
-       "web-server" (base32 "1g4x79ym3mgxv4f3z3z84j12355pf44pjlzlb7f0h6r0i7p0cbjd")
+       "web-server" (base32 "104lnzjykkd6f3gxpv7p14l94if6zac33nmb4sj5jxmd6r3fwcpf")
        '("web-server" "web-server-doc" "web-server-lib"))
       (simple-racket-origin
        "wxme" (base32 "1qp5gr9gqsakiq3alw6m4yyv5vw4i3hp4y4nhq8vl2nkjmirvn0b")