diff --git a/racket/src/ChezScheme/README.md b/racket/src/ChezScheme/README.md
index 5821dd3495..fac65a93c4 100644
--- a/racket/src/ChezScheme/README.md
+++ b/racket/src/ChezScheme/README.md
@@ -12,6 +12,8 @@ Supported platforms:
  * OpenBSD: x86, x86_64
  * NetBSD: x86, x86_64
  * Solaris: x86, x86_64
+ * Android: ARMv7, AArch64
+ * iOS: AArch64
 
 As a superset of the language described in the
 [Revised<sup>6</sup> Report on the Algorithmic Language Scheme](http://www.r6rs.org)
diff --git a/racket/src/ChezScheme/c/Mf-base b/racket/src/ChezScheme/c/Mf-base
index 2dddc636a7..65b16b93be 100644
--- a/racket/src/ChezScheme/c/Mf-base
+++ b/racket/src/ChezScheme/c/Mf-base
@@ -22,7 +22,7 @@ Main=../boot/$m/main.$o
 Scheme=../bin/$m/scheme
 
 # CFLAGS is propagated separately:
-SetConfigEnv = CC="${CC}" CPPFLAGS="${CPPFLAGS}" AR="${AR}" ARFLAGS="${ARFLAGS}"
+SetConfigEnv = CC="${CC}" CPPFLAGS="${CPPFLAGS}" AR="${AR}" ARFLAGS="${ARFLAGS}" RANLIB="${RANLIB}"
 
 # One of these sets is referenced in Mf-config to select between
 # linking with kernel.o or libkernel.a
diff --git a/racket/src/ChezScheme/c/atomic.h b/racket/src/ChezScheme/c/atomic.h
index 854de274b5..8610394748 100644
--- a/racket/src/ChezScheme/c/atomic.h
+++ b/racket/src/ChezScheme/c/atomic.h
@@ -5,7 +5,7 @@
 # define ACQUIRE_FENCE() __asm__ __volatile__ ("dmb ish" : : : "memory")
 # define RELEASE_FENCE() ACQUIRE_FENCE()
 #elif defined(__arm__)
-# if arm_isa_version == 7
+# if (arm_isa_version >= 7) || (__ARM_ARCH >= 7)
 #  define STORE_FENCE() __asm__ __volatile__ ("dmb ishst" : : : "memory")
 #  define ACQUIRE_FENCE() __asm__ __volatile__ ("dmb ish" : : : "memory")
 #  define RELEASE_FENCE() ACQUIRE_FENCE()
@@ -72,15 +72,18 @@ FORCEINLINE int CAS_STORE_RELEASE(volatile void *addr, void *old_val, void *new_
   return ret;
 }
 #elif defined(__arm__)
-FORCEINLINE int S_cas_any_fence(volatile void *addr, void *old_val, void *new_val) {
+FORCEINLINE int S_cas_any_fence(int load_acquire, volatile void *addr, void *old_val, void *new_val) {
   int ret;
-  __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5\n\t"
-                        "mov %0, #0\n\t"       
+  if (load_acquire)
+    ACQUIRE_FENCE();
+  else
+    RELEASE_FENCE();
+  __asm__ __volatile__ ("mov %0, #0\n\t"
                         "0:\n\t"
-                        "ldrex r12, [%1, #0]\n\t"
+                        "ldrex r12, [%1]\n\t"
                         "cmp r12, %2\n\t"
                         "bne 1f\n\t"
-                        "strex r7, %3, [%1, #0]\n\t"
+                        "strex r7, %3, [%1]\n\t"
                         "cmp r7, #0\n\t"
                         "bne 1f\n\t"
                         "it eq\n\t"
@@ -91,7 +94,8 @@ FORCEINLINE int S_cas_any_fence(volatile void *addr, void *old_val, void *new_va
                         : "cc", "memory", "r12", "r7");
   return ret;
 }
-# define CAS_ANY_FENCE(a, old, new) S_cas_any_fence(a, old, new)
+# define CAS_LOAD_ACQUIRE(a, old, new) S_cas_any_fence(1, a, old, new)
+# define CAS_STORE_RELEASE(a, old, new) S_cas_any_fence(0, a, old, new)
 #elif (__GNUC__ >= 5) || defined(__clang__)
 # define CAS_ANY_FENCE(a, old, new) __sync_bool_compare_and_swap(a, old, new)
 #elif defined(_MSC_VER)
diff --git a/racket/src/ChezScheme/c/prim5.c b/racket/src/ChezScheme/c/prim5.c
index 905d3859fc..f718afeb79 100644
--- a/racket/src/ChezScheme/c/prim5.c
+++ b/racket/src/ChezScheme/c/prim5.c
@@ -2088,7 +2088,12 @@ static void s_free(uptr addr) {
 }
 
 #ifdef FEATURE_ICONV
-#ifdef WIN32
+#ifdef DISABLE_ICONV
+# define iconv_t int
+#define ICONV_OPEN(to, from) -1
+#define ICONV(cd, in, inb, out, outb) -1
+#define ICONV_CLOSE(cd) -1
+#elif defined(WIN32)
 typedef void *iconv_t;
 typedef iconv_t (*iconv_open_ft)(const char *tocode, const char *fromcode);
 typedef size_t (*iconv_ft)(iconv_t cd, char **inbuf, size_t *inbytesleft, char **outbuf, size_t *outbytesleft);
diff --git a/racket/src/ChezScheme/c/version.h b/racket/src/ChezScheme/c/version.h
index 7adcbed8b0..0d8ddcece6 100644
--- a/racket/src/ChezScheme/c/version.h
+++ b/racket/src/ChezScheme/c/version.h
@@ -134,7 +134,9 @@ typedef char *memcpy_t;
 #define MAKE_NAN(x) { x = 0.0; x = x / x; }
 #define GETWD(x) getcwd((x),PATH_MAX)
 typedef int tputsputcchar;
-#define LOCKF
+#ifndef __ANDROID__
+# define LOCKF
+#endif
 #define DIRMARKERP(c) ((c) == '/')
 #ifndef DISABLE_X11
 # define LIBX11 "libX11.so"
@@ -149,6 +151,10 @@ typedef int tputsputcchar;
 #define NSECCTIME(sb) (sb).st_ctim.tv_nsec
 #define NSECMTIME(sb) (sb).st_mtim.tv_nsec
 #define ICONV_INBUF_TYPE char **
+#ifdef __ANDROID__
+# define NOFILE 256
+# define NO_USELOCALE
+#endif
 #define UNUSED __attribute__((__unused__))
 #endif
 
@@ -175,7 +181,7 @@ typedef int tputsputcchar;
 #define SECMTIME(sb) (sb).st_mtimespec.tv_sec
 #define NSECATIME(sb) (sb).st_atimespec.tv_nsec
 #define NSECCTIME(sb) (sb).st_ctimespec.tv_nsec
-#define NSECMTIME(sb) (sb).st_mtimespec.tv_nsec
+#define NSECM<TIME(sb) (sb).st_mtimespec.tv_nsec
 #define ICONV_INBUF_TYPE char **
 #define UNUSED __attribute__((__unused__))
 #define USE_OSSP_UUID
diff --git a/racket/src/ChezScheme/configure b/racket/src/ChezScheme/configure
index 23f5804fc2..87be80a3b8 100755
--- a/racket/src/ChezScheme/configure
+++ b/racket/src/ChezScheme/configure
@@ -57,6 +57,7 @@ installscriptname="scheme-script"
 cflagsset=no
 disablex11=no
 disablecurses=no
+disableiconv=no
 addflags=yes
 addwarningflags=no
 default_warning_flags="-Wpointer-arith -Wall -Wextra -Werror -Wno-implicit-fallthrough"
@@ -273,6 +274,9 @@ while [ $# != 0 ] ; do
     --disable-curses)
       disablecurses=yes
       ;;
+    --disable-iconv)
+      disableiconv=yes
+      ;;
     --disable-auto-flags)
       addflags=no
       ;;
@@ -420,6 +424,7 @@ if [ "$help" = "yes" ]; then
   echo "  --32|--64                         specify 32/64-bit version ($bits)"
   echo "  --disable-x11                     disable X11 support"
   echo "  --disable-curses                  disable [n]curses support"
+  echo "  --disable-iconv                   disable iconv support"
   echo "  --disable-auto-flags              no auto additions to CFLAGS/LDFLAGS/LIBS"
   echo "  --enable-warning-flags            add GCC warning flags to CFLAGS"
   echo "  --libkernel                       build libkernel.a (the default)"
@@ -565,6 +570,13 @@ if [ "$disablecurses" = "yes" ]; then
   ncursesLib=
 fi
 
+if [ "$disableiconv" = "yes" ]; then
+    iconvLib=
+    CPPFLAGS="${CPPFLAGS} -DDISABLE_ICONV"
+else
+    iconvLib="-liconv"
+fi
+
 # Add automatic linking flags, unless suppressed by --disable-auto-flags
 if [ "$addflags" = "yes" ] ; then
   case "${flagsm}" in
@@ -586,22 +598,28 @@ if [ "$addflags" = "yes" ] ; then
         LIBS="${LIBS} -lm -ldl ${ncursesLib} -lrt"
         ;;
     *fb|*ob)
-        LIBS="${LIBS} -liconv -lm ${ncursesLib}"
+        LIBS="${LIBS} ${iconvLib} -lm ${ncursesLib}"
         ;;
     *nb)
-        LIBS="${LIBS} /usr/lib/i18n/libiconv_std.a -lm /usr/pkg/lib/libncurses.a"
+        if [ "$disablecurses" = "no" ]; then
+            iconvLib="/usr/lib/i18n/libiconv_std.a"
+        fi
+        LIBS="${LIBS} ${iconvLib} -lm /usr/pkg/lib/libncurses.a"
         ;;
     *s2)
         LIBS="${LIBS} -lnsl -ldl -lm ${cursesLib} -lrt"
         ;;
     *osx)
-        LIBS="${LIBS} -liconv -lm ${ncursesLib}"
+        LIBS="${LIBS} ${iconvLib} -lm ${ncursesLib}"
         ;;
     *nt)
         LIBS="${LIBS} -lshell32 -luser32 -lole32 -lrpcrt4 -luuid"
         ;;
     8qnx)
-        LIBS="${LIBS} -lm /usr/local/lib/libiconv.so -lsocket ${ncursesLib}"
+        if [ "$disablecurses" = "no" ]; then
+            iconvLib="/usr/local/lib/libiconv.so"
+        fi
+        LIBS="${LIBS} -lm ${iconvLib} -lsocket ${ncursesLib}"
         ;;
   esac
   if [ "$threadLibs" != "" ] ; then
diff --git a/racket/src/ChezScheme/s/mkheader.ss b/racket/src/ChezScheme/s/mkheader.ss
index 6c5ca768b2..0532cff37d 100644
--- a/racket/src/ChezScheme/s/mkheader.ss
+++ b/racket/src/ChezScheme/s/mkheader.ss
@@ -734,7 +734,7 @@
             (nl)
             (pr "#define SPINLOCK(addr)      \\~%")
             (pr "  __asm__ __volatile__ (\"0:\\n\\t\"\\~%")
-            (pr "                        \"ldrex r12, [%0, #0]\\n\\t\"\\~%")
+            (pr "                        \"ldrex r12, [%0]\\n\\t\"\\~%")
             (pr "                        \"cmp r12, #0\\n\\t\"\\~%")
             (pr "                        \"bne 1f\\n\\t\"\\~%")
             (pr "                        \"mov r12, #1\\n\\t\"\\~%")
@@ -763,7 +763,7 @@
             (pr "#define LOCKED_INCR(addr, ret) \\~%")
             (pr "  __asm__ __volatile__ (\"mov %0, #0\\n\\t\"\\~%")
             (pr "                        \"0:\\n\\t\"\\~%")
-            (pr "                        \"ldrex r12, [%1, #0]\\n\\t\"\\~%")
+            (pr "                        \"ldrex r12, [%1]\\n\\t\"\\~%")
             (pr "                        \"add r12, r12, #1\\n\\t\"\\~%")
             (pr "                        \"strex r7, r12, [%1]\\n\\t\"\\~%")
             (pr "                        \"cmp r7, #0\\n\\t\"\\~%")
@@ -779,7 +779,7 @@
             (pr "#define LOCKED_DECR(addr, ret) \\~%")
             (pr "  __asm__ __volatile__ (\"mov %0, #0\\n\\t\"\\~%")
             (pr "                        \"0:\\n\\t\"\\~%")
-            (pr "                        \"ldrex r12, [%1, #0]\\n\\t\"\\~%")
+            (pr "                        \"ldrex r12, [%1]\\n\\t\"\\~%")
             (pr "                        \"sub r12, r12, #1\\n\\t\"\\~%")
             (pr "                        \"strex r7, r12, [%1]\\n\\t\"\\~%")
             (pr "                        \"cmp r7, #0\\n\\t\"\\~%")
diff --git a/racket/src/Makefile.in b/racket/src/Makefile.in
index 608e17ba2b..4c913a480c 100644
--- a/racket/src/Makefile.in
+++ b/racket/src/Makefile.in
@@ -94,7 +94,7 @@ no-local-racket:
 @RUN_LOCAL_RACKET@:
 	mkdir -p local
 	$(MAKE) local/Makefile
-	cd local && $(MAKE)
+	cd local && $(MAKE) @LOCAL_RACKET_TARGET@
 
 local/Makefile:
 	cd local && `cd ..; cd $(srcdir); pwd`/configure --disable-gracket @CONFIGURE_LOCAL_RACKET@
diff --git a/racket/src/README.txt b/racket/src/README.txt
index 3b2580f430..befd9adaac 100644
--- a/racket/src/README.txt
+++ b/racket/src/README.txt
@@ -371,66 +371,84 @@ Some less commonly needed `configure` flags are for Racket BC:
  Cross-compiling for Android
 ========================================================================
 
-[Currently, cross-compilation for Android works only for the Racket BC
- implementation.]
-
-As an example of cross-compiling, to compile for Android on ARM using
-the NDK, use (all on one line)
+As an example of cross-compiling Racket for Android on ARMv7 using the
+NDK, use (all on one line)
 
   configure --host=arm-linux-androideabi 
-            --enable-sysroot="[ndk]/platforms/android-[N]/arch-arm"
+            --enable-sysroot="[sysroot]"
             --enable-racket=auto
 
-where [ndk] is the path to the installed NDK, [N] is a target version
-of Android (such as 14), and
+If you use the NDK script "make-standalone-toolchain.sh" to generate a
+toolchain directory, then include that directory's "bin" in your PATH
+(so that `arm-linux-androideabi-gcc`, etc., are found), and you can
+omit `--enable-sysroot` (or specify [sysroot] as the toolchain
+directory's "sysroot" subdirectory).
+
+In other NDK configurations, you may have
 
  [ndk]/toolchains/arm-linux-androideabi-[comp]/prebuilt/[platform]/bin
 
-is in your PATH (so that a suitable `gcc`, `ar`, etc., are found) for
-the [comp] of your choice and the [platform] used to compile.
+in your PATH (so that `arm-linux-androideabi-gcc`, etc., are found)
+where [ndk] is the path to the installed NDK and for the [comp] of
+your choice and the [platform] used to compile, and then [sysroot] is
+
+ [ndk]/platforms/android-[N]/arch-arm
+
+where [N] is a target version of Android (such as 14).
+
+For 64-bit ARM, replace "arm" above with "aarch64", and replace
+"androideabi" with "android".
+
+When building BC, you may need to add `--disable-cify` for 32-bit ARM
+and `--enable-cify` for 64-bit ARM instead of inheriting the build
+machine's disposition.
 
 
 ========================================================================
  Cross-compiling for iOS
 ========================================================================
 
-To compile the Racket BC runtime system as a Framework for iOS, use
-(all on one line)
+To compile the Racket runtime system as a Framework for iOS, use (all
+on one line)
 
   configure --host=[arch]-apple-darwin
             --enable-ios="[sdk]"
-            --enable-racket=racket
-            --enable-bcdefault
+            --enable-racket=auto
 
 where [arch] is one of
 
  - armv7, armv7s, or aarch64: to run on iOS
- - i386 or x86_64: to run on the simulator
+ - x86_64 or aarch64: to run on the simulator
 
-The [sdk] argument is a path to an iOS SDK, but if it is "iPhoneOS" or
-"iPhoneSimulator", then the corresponding SDK is located in the
-standard place within the XCode application. For example, "iPhoneOS"
-becomes the path (all on one line)
+The [sdk] argument is a path to an iOS SDK for "iPhoneOS" or
+"iPhoneSimulator". The corresponding SDK is located in the standard
+place within the XCode application. For example, "iPhoneOS" becomes
+the path (all on one line)
 
   /Applications/Xcode.app/Contents/Developer/Platforms/
     iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk
 
-To cross-compile for CS, you must supply the Chez Scheme compiler that
-Racket CS was built with.  Assuming you have built Racket CS for your
-machine at "/path/to/racket" using the default `make` target, you can
-configure the cross build using that Racket binary and a path to the
-Chez Scheme build folder as follows (all on one line)
+To use an existing Racket build for the build platform using
+`--enable-racket`, be sure to include `--enable-scheme` for Racket CS.
+For example, if you have built Racket CS for your machine at
+"/path/to/racket" using the default `make` target, you can configure
+the cross build using that Racket binary and a path to the Chez Scheme
+build folder as follows (all on one line)
 
   configure --host=[arch]-apple-darwin
             --enable-ios="[sdk]"
             --enable-racket=/path/to/racket/bin/racket
             --enable-scheme=/path/to/racket/src/build/cs/c
 
-Currently, iOS enforces strict W^X protection on memory pages. See the
-note about "writes to `space_code` memory" in "ChezScheme/c/segment.c"
-for the implications this has on Racket CS. In principle, if you avoid
-passing newly-allocated code between threads and avoid `#:blocking?`
-foreign callbacks, you should not run into any issues.
+Currently, iOS enforces W^X protection on memory pages, which is
+technically a problem for Racket CS. See the note about "writes to
+`space_code` memory" in "ChezScheme/c/segment.c" for the implications.
+If you avoid passing newly-allocated code between threads and avoid
+`#:blocking?` foreign callbacks, you might not run into any issues.
+
+When building BC for iOS, you may need to add `--disable-cify` for
+32-bit target and `--enable-cify` for 64-bit target instead of
+inheriting the build machine's disposition.
 
 
 ========================================================================
diff --git a/racket/src/bc/configure-parent.ac b/racket/src/bc/configure-parent.ac
index d73ac45a9f..db8ad15f32 100644
--- a/racket/src/bc/configure-parent.ac
+++ b/racket/src/bc/configure-parent.ac
@@ -40,6 +40,7 @@ if test "${enable_racket}" = "auto" ; then
 fi
 RUN_LOCAL_RACKET="local/bc/racket3m"
 CONFIGURE_LOCAL_RACKET=--enable-bc
+LOCAL_RACKET_TARGET=bc
 
 if test "${enable_cgcdefault}" = "yes" ; then
   MAIN_VARIANT=cgc
@@ -62,6 +63,7 @@ AC_SUBST(RUN_RACKET)
 AC_SUBST(MAKE_LOCAL_RACKET)
 AC_SUBST(RUN_LOCAL_RACKET)
 AC_SUBST(CONFIGURE_LOCAL_RACKET)
+AC_SUBST(LOCAL_RACKET_TARGET)
 
 makefiles="Makefile"
 
diff --git a/racket/src/cfg-bc b/racket/src/cfg-bc
index 5c4f11d76e..8cad106f70 100755
--- a/racket/src/cfg-bc
+++ b/racket/src/cfg-bc
@@ -585,6 +585,7 @@ ac_unique_file="setup-go.rkt"
 enable_option_checking=no
 ac_subst_vars='LTLIBOBJS
 LIBOBJS
+LOCAL_RACKET_TARGET
 CONFIGURE_LOCAL_RACKET
 RUN_LOCAL_RACKET
 RUN_RACKET
@@ -2330,6 +2331,7 @@ if test "${enable_racket}" = "auto" ; then
 fi
 RUN_LOCAL_RACKET="local/bc/racket3m"
 CONFIGURE_LOCAL_RACKET=--enable-bc
+LOCAL_RACKET_TARGET=bc
 
 if test "${enable_cgcdefault}" = "yes" ; then
   MAIN_VARIANT=cgc
@@ -2353,6 +2355,7 @@ fi
 
 
 
+
 makefiles="Makefile"
 
 ac_config_files="$ac_config_files $makefiles"
diff --git a/racket/src/cfg-cs b/racket/src/cfg-cs
index fe2134449c..5f3df3b675 100755
--- a/racket/src/cfg-cs
+++ b/racket/src/cfg-cs
@@ -585,6 +585,7 @@ ac_unique_file="setup-go.rkt"
 enable_option_checking=no
 ac_subst_vars='LTLIBOBJS
 LIBOBJS
+LOCAL_RACKET_TARGET
 CONFIGURE_LOCAL_RACKET
 RUN_LOCAL_RACKET
 RUN_RACKET
@@ -2239,6 +2240,7 @@ if test "${enable_racket}" = "auto" ; then
 fi
 RUN_LOCAL_RACKET="local/cs/c/racketcs"
 CONFIGURE_LOCAL_RACKET=--enable-cs
+LOCAL_RACKET_TARGET=cs
 
 # If BC is the default, then we rely on BC configure-parent
 # being used instead of this one:
@@ -2256,6 +2258,7 @@ fi
 
 
 
+
 makefiles="Makefile"
 
 ac_config_files="$ac_config_files $makefiles"
diff --git a/racket/src/cs/c/Makefile.in b/racket/src/cs/c/Makefile.in
index 258a437c1a..6bdd797ec6 100644
--- a/racket/src/cs/c/Makefile.in
+++ b/racket/src/cs/c/Makefile.in
@@ -155,6 +155,11 @@ mach-make:
 	$(MAKE) config-scheme
 	cd $(SCHEME_WORKAREA) && $(MAKE)
 
+# Makes cross compilation work more reliably for zlib, because
+# it causes zlib/configure to use given AR, etc.
+CHOST_HACK-cross = env "CHOST=hack-do-not-use"
+CHOST_HACK =
+
 SCHEME_CONFIG_VARS = CC="$(CC)" CFLAGS="$(BASE_CFLAGS)" LDFLAGS="$(LDFLAGS)" LIBS="$(LIBS)" \
                      AR="$(AR)" ARFLAGS="$(ARFLAGS)" RANLIB="$(RANLIB)" \
                      WINDRES="$(WINDRES)"
@@ -167,7 +172,7 @@ scheme-cross:
 	env MAKE_BOOT_FOR_CROSS=yes SCHEME_SRC="$(SCHEME_DIR)" SCHEME_WORKAREA=$(SCHEME_WORKAREA) MACH="$(TARGET_MACH)" $(BOOTSTRAP_RACKET) "$(SCHEME_DIR)"/rktboot/make-boot.rkt
 	/bin/sh $(srcdir)/reset_boot.sh $(TARGET_MACH) $(SCHEME_WORKAREA)
 	cd $(SCHEME_WORKAREA) && "$(UP_SCHEME_DIR)"/configure @SCHEME_CROSS_CONFIG_ARGS@ $(SCHEME_CONFIG_VARS)
-	cd $(SCHEME_WORKAREA)/$(TARGET_MACH)/c && $(MAKE) o=o cross=t
+	cd $(SCHEME_WORKAREA)/$(TARGET_MACH)/c && $(CHOST_HACK@T_CROSS_MODE@) $(MAKE) o=o cross=t
 	$(MAKE) $(SCHEME_WORKAREA)/$(TARGET_MACH)/s/xpatch
 
 # Rebuild patch file and cross "petite.boot" and "scheme.boot" when older
@@ -200,11 +205,11 @@ racket.boot: racket.so
 EMBED_DEPS = $(srcdir)/embed-boot.rkt
 
 racketcs@NOT_OSX@@NOT_MINGW@: raw_racketcs petite-v.boot scheme-v.boot racket-v.boot $(EMBED_DEPS)
-	$(BOOTSTRAP_RACKET) $(srcdir)/embed-boot.rkt @ELF_COMP@ @BOOT_COMPRESS_COMP@ raw_racketcs racketcs petite-v.boot scheme-v.boot racket-v.boot
+	$(BOOTSTRAP_RACKET) $(srcdir)/embed-boot.rkt @ELF_COMP@ --target $(TARGET_MACH) @BOOT_COMPRESS_COMP@ raw_racketcs racketcs petite-v.boot scheme-v.boot racket-v.boot
 	@POST_LINKER@ racketcs
 
 gracketcs@NOT_OSX@@NOT_MINGW@: raw_gracketcs petite-v.boot scheme-v.boot racket-v.boot $(EMBED_DEPS)
-	$(BOOTSTRAP_RACKET) $(srcdir)/embed-boot.rkt @ELF_COMP@ @BOOT_COMPRESS_COMP@ raw_gracketcs gracketcs petite-v.boot scheme-v.boot racket-v.boot
+	$(BOOTSTRAP_RACKET) $(srcdir)/embed-boot.rkt @ELF_COMP@ --target $(TARGET_MACH) @BOOT_COMPRESS_COMP@ raw_gracketcs gracketcs petite-v.boot scheme-v.boot racket-v.boot
 	@POST_LINKER@ gracketcs
 
 OWN_Z_LIB = $(SCHEME_TARGET_INC)/../../zlib/libz.a
diff --git a/racket/src/cs/c/configure b/racket/src/cs/c/configure
index f69b03451b..81fc52f3b8 100755
--- a/racket/src/cs/c/configure
+++ b/racket/src/cs/c/configure
@@ -4304,7 +4304,8 @@ case "$host_os" in
     MACH_OS=fb
     CFLAGS="${CFLAGS} -I/usr/local/include"
     LDFLAGS="${LDFLAGS} -L/usr/local/lib"
-    LIBS="${LIBS} -liconv -lm -lpthread"
+    LIBS="${LIBS} -lm -lpthread"
+    add_iconv_lib="-liconv"
     CPPFLAGS="${CPPFLAGS} -DELF_FIND_BOOT_SECTION"
     ELF_COMP="--expect-elf"
     ;;
@@ -4312,7 +4313,8 @@ case "$host_os" in
     MACH_OS=ob
     CFLAGS="${CFLAGS} -I/usr/local/include"
     LDFLAGS="${LDFLAGS} -L/usr/local/lib"
-    LIBS="${LIBS} -liconv -lm -lpthread"
+    LIBS="${LIBS} -lm -lpthread"
+    add_iconv_lib="-liconv"
     LDFLAGS="${LDFLAGS} -Wl,-zwxneeded"
     CPPFLAGS="${CPPFLAGS} -DELF_FIND_BOOT_SECTION"
     ELF_COMP="--expect-elf"
@@ -4323,7 +4325,8 @@ case "$host_os" in
     ;;
   netbsd*)
     MACH_OS=nb
-    LIBS="${LIBS} /usr/lib/i18n/libiconv_std.a -lm -lpthread"
+    LIBS="${LIBS} -lm -lpthread"
+    add_iconv_lib="/usr/lib/i18n/libiconv_std.a"
     CPPFLAGS="${CPPFLAGS} -DELF_FIND_BOOT_SECTION"
     ELF_COMP="--expect-elf"
     POST_LINKER="paxctl +m"
@@ -4332,7 +4335,13 @@ case "$host_os" in
     ;;
   linux*)
     MACH_OS=le
-    LIBS="${LIBS} -lrt"
+    case "$host_os" in
+      *linux-android*)
+        ;;
+      *)
+        LIBS="${LIBS} -lrt"
+        ;;
+    esac
     CPPFLAGS="${CPPFLAGS} -DELF_FIND_BOOT_SECTION"
     ELF_COMP="--expect-elf"
     ;;
@@ -5343,6 +5352,8 @@ if test "${enable_iconv}" = "no" ; then
 
 $as_echo "#define RKTIO_NO_ICONV 1" >>confdefs.h
 
+  extra_scheme_config_args="${extra_scheme_config_args} --disable-iconv"
+  add_iconv_lib=
 fi
 
 if test "${enable_iconv}" = "yes" ; then
@@ -5373,6 +5384,10 @@ rm -f core conftest.err conftest.$ac_objext \
 $as_echo "$have_codeset" >&6; }
 fi
 
+if test "${add_iconv_lib}" != "" ; then
+    LIBS="${LIBS} ${add_iconv_lib}"
+fi
+
 ############### pthread ###################
 
 if test "${enable_pthread}" = "yes" ; then
diff --git a/racket/src/cs/c/configure-parent.ac b/racket/src/cs/c/configure-parent.ac
index 4c3f82c198..6b00eb6d46 100644
--- a/racket/src/cs/c/configure-parent.ac
+++ b/racket/src/cs/c/configure-parent.ac
@@ -30,6 +30,7 @@ if test "${enable_racket}" = "auto" ; then
 fi
 RUN_LOCAL_RACKET="local/cs/c/racketcs"
 CONFIGURE_LOCAL_RACKET=--enable-cs
+LOCAL_RACKET_TARGET=cs
 
 # If BC is the default, then we rely on BC configure-parent
 # being used instead of this one:
@@ -46,6 +47,7 @@ AC_SUBST(RUN_RACKET)
 AC_SUBST(MAKE_LOCAL_RACKET)
 AC_SUBST(RUN_LOCAL_RACKET)
 AC_SUBST(CONFIGURE_LOCAL_RACKET)
+AC_SUBST(LOCAL_RACKET_TARGET)
 
 makefiles="Makefile"
 
diff --git a/racket/src/cs/c/configure.ac b/racket/src/cs/c/configure.ac
index c5305c425e..56262a27cc 100644
--- a/racket/src/cs/c/configure.ac
+++ b/racket/src/cs/c/configure.ac
@@ -220,7 +220,8 @@ case "$host_os" in
     MACH_OS=fb
     CFLAGS="${CFLAGS} -I/usr/local/include"
     LDFLAGS="${LDFLAGS} -L/usr/local/lib"
-    LIBS="${LIBS} -liconv -lm -lpthread"
+    LIBS="${LIBS} -lm -lpthread"
+    add_iconv_lib="-liconv"
     CPPFLAGS="${CPPFLAGS} -DELF_FIND_BOOT_SECTION"
     ELF_COMP="--expect-elf"
     ;;
@@ -228,7 +229,8 @@ case "$host_os" in
     MACH_OS=ob
     CFLAGS="${CFLAGS} -I/usr/local/include"
     LDFLAGS="${LDFLAGS} -L/usr/local/lib"
-    LIBS="${LIBS} -liconv -lm -lpthread"
+    LIBS="${LIBS} -lm -lpthread"
+    add_iconv_lib="-liconv"
     LDFLAGS="${LDFLAGS} -Wl,-zwxneeded"
     CPPFLAGS="${CPPFLAGS} -DELF_FIND_BOOT_SECTION"
     ELF_COMP="--expect-elf"
@@ -239,7 +241,8 @@ case "$host_os" in
     ;;
   netbsd*)
     MACH_OS=nb
-    LIBS="${LIBS} /usr/lib/i18n/libiconv_std.a -lm -lpthread"
+    LIBS="${LIBS} -lm -lpthread"
+    add_iconv_lib="/usr/lib/i18n/libiconv_std.a"
     CPPFLAGS="${CPPFLAGS} -DELF_FIND_BOOT_SECTION"
     ELF_COMP="--expect-elf"
     POST_LINKER="paxctl +m"
@@ -248,7 +251,13 @@ case "$host_os" in
     ;;
   linux*)
     MACH_OS=le
-    LIBS="${LIBS} -lrt"
+    case "$host_os" in
+      *linux-android*)
+        ;;
+      *)
+        LIBS="${LIBS} -lrt"
+        ;;
+    esac
     CPPFLAGS="${CPPFLAGS} -DELF_FIND_BOOT_SECTION"
     ELF_COMP="--expect-elf"
     ;;
@@ -529,6 +538,8 @@ AC_LANG_C
 m4_include(../ac/iconv.m4)
 if test "${enable_iconv}" = "no" ; then
   AC_DEFINE(RKTIO_NO_ICONV,1,[Do not use iconv])
+  extra_scheme_config_args="${extra_scheme_config_args} --disable-iconv"
+  add_iconv_lib=
 fi
 
 if test "${enable_iconv}" = "yes" ; then
@@ -541,6 +552,10 @@ if test "${enable_iconv}" = "yes" ; then
   AC_MSG_RESULT($have_codeset)
 fi
 
+if test "${add_iconv_lib}" != "" ; then
+    LIBS="${LIBS} ${add_iconv_lib}"
+fi
+
 ############### pthread ###################
 
 if test "${enable_pthread}" = "yes" ; then
diff --git a/racket/src/rktio/configure b/racket/src/rktio/configure
index 9e718f57fc..da6931ea1b 100755
--- a/racket/src/rktio/configure
+++ b/racket/src/rktio/configure
@@ -4231,7 +4231,7 @@ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
       return 0;
    }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"; then :
 
 $as_echo "#define RKTIO_USE_XLOCALE 1" >>confdefs.h
 
@@ -4239,7 +4239,8 @@ $as_echo "#define RKTIO_USE_XLOCALE 1" >>confdefs.h
 else
   xlocaleon=no
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $xlocaleon" >&5
 $as_echo "$xlocaleon" >&6; }
 CFLAGS="$SAVE_CFLAGS"
diff --git a/racket/src/rktio/configure.ac b/racket/src/rktio/configure.ac
index bee78e0361..830d7fbe1f 100644
--- a/racket/src/rktio/configure.ac
+++ b/racket/src/rktio/configure.ac
@@ -175,7 +175,7 @@ if test "${xlocalehon}" = "yes" ; then
 fi
 [ msg="for xlocale functions" ]
 AC_MSG_CHECKING($msg)
-AC_COMPILE_IFELSE([AC_LANG_SOURCE([
+AC_LINK_IFELSE([AC_LANG_SOURCE([
    #ifdef RKTIO_USE_XLOCALE_HEADER
    # include <xlocale.h>
    #endif
diff --git a/racket/src/rktio/rktio_platform.h b/racket/src/rktio/rktio_platform.h
index 52538a9bb5..cbbe1818c4 100644
--- a/racket/src/rktio/rktio_platform.h
+++ b/racket/src/rktio/rktio_platform.h
@@ -50,6 +50,7 @@
 
 # ifdef __ANDROID__
 #  define PROTOENT_IS_INT IPPROTO_TCP
+#  define NO_PTHREAD_CANCEL
 # endif
 
 #endif
@@ -342,3 +343,7 @@
     standalone Racket. Used only if NO_SLEEP is undefined. */
 
  /* NO_STRERROR_AVAILABLE means that strerror() is not available. */
+
+ /* NO_PTHREAD_CANCEL means that pthread_setcanceltype() is
+    not available, which means it can't be used to implement
+    non-blocking open(). */
diff --git a/racket/src/rktio/rktio_private.h b/racket/src/rktio/rktio_private.h
index e4bccc6830..f81cb41523 100644
--- a/racket/src/rktio/rktio_private.h
+++ b/racket/src/rktio/rktio_private.h
@@ -360,7 +360,7 @@ void rktio_close_fds_after_fork(int len, int skip1, int skip2, int skip3);
 
 int rktio_system_fd_is_terminal(rktio_t *rktio, intptr_t fd);
 
-#ifdef RKTIO_USE_PTHREADS
+#if defined(RKTIO_USE_PTHREADS) && !defined(NO_PTHREAD_CANCEL)
 # define RKTIO_USE_PENDING_OPEN
 #endif