anchor.diff:      ./configure -cc "gcc -m32" -as "as --32" -aspp "gcc -m32 -c" \
                   -host i386-linux -partialld "ld -r -melf_i386"
   
  -* On a Linux x86-64 host, to build the run-time system in PIC mode,
  -  no special options should be required---the libraries should be built
  -  automatically.  The old instructions were:
  +* On a Linux x86-64 host, to build the run-time system in PIC mode, no special
  +  options should be required -- the libraries should be built automatically.
  +  The old instructions were:
   
       ./configure -cc "gcc -fPIC" -aspp "gcc -c -fPIC"
   +
  -On a 64-bit POWER architecture host running Linux, OCaml only operates
  -  in a 32-bit environment.  If your system compiler is configured as 32-bit,
  -  e.g. Red Hat 5.9, you don't need to do anything special.  If that is
  -  not the case (e.g. Red Hat 6.4), then IBM's "Advance Toolchain" can
  -  be used.  For example:
  +On a 64-bit POWER architecture host running Linux, OCaml only operates in a
  +  32-bit environment.  If your system compiler is configured as 32-bit, e.g.
  +  Red Hat 5.9, you don't need to do anything special.  If that is not the case
  +  (e.g. Red Hat 6.4), then IBM's "Advance Toolchain" can be used.  For example:
   
       export PATH=/opt/at7.0/bin:$PATH
       ./configure -cc "gcc -m32" -as "as -a32" -aspp "gcc -m32 -c" \
         -partialld "ld -r -m elf32ppc"
   
  -* On a MacOSX 10.5/Intel Core 2 or MacOSX 10.5/PowerPC host,
  -  to build a 64-bit version of OCaml:
  +* On a OS X 10.5/Intel Core 2 or OS X 10.5/PowerPC host, to build a 64-bit
  +  version of OCaml:
  +
       ./configure -cc "gcc -m64"
   
  -* On Intel Mac OS X, to build a 32-bit version of OCaml:
  +* On OS X Intel, to build a 32-bit version of OCaml:
   
       ./configure -host "i386-apple-darwin13.2.0" -cc "gcc -arch i386 -m32" \
         -as "as -arch i386" -aspp "gcc -arch i386 -m32 -c"
   
  -* For Sun Solaris with the "acc" compiler:
  +* For Sun Solaris with the `acc` compiler:
   
       ./configure -cc "acc -fast" -libs "-lucb"
   
  
positive.code: 
      ./configure -cc "gcc -m32" -as "as -32" -aspp "gcc -m32 -c"
  
  * For AIX 4.3 with the IBM compiler xlc:
  
      ./configure -cc "xlc_r -D_AIX43 -Wl,-bexpall,-brtl -qmaxmem=8192"
  +
  If something goes wrong during the automatic configuration, or if the
  generated files cause errors later on, then look at the template files
  
          config/Makefile-templ
          config/m-templ.h
  
negative.code: 
          ./configure
  +
  This generates the three configuration files `Makefile`, `m.h` and `s.h`
  in the `config/` subdirectory.
  +
  The `configure` script accepts the following options:
  +
  `-prefix <dir>`::                   (default: `/usr/local`)
          Set the `PREFIX` variable used to define the defaults of the following
          three options.  Must be an absolute path name.
  
  `-bindir <dir>`::                   (default: `$(PREFIX)/bin`)
          Directory where the binaries will be installed.  Must be an absolute
          path name, or start with `$(PREFIX)`.
  
  `-libdir <dir>`::                   (default: `$(PREFIX)/lib/ocaml`)
          Directory where the OCaml library will be installed.  Must be an
          absolute path name, or start with `$(PREFIX)`.
  
  `-mandir <dir>`::                   (default: `$(PREFIX)/man/man1`)
          Directory where the manual pages will be installed.  Must be an absolute
          path name, or start with `$(PREFIX)`.
  
  `-cc <C compiler and options>`::    (default: `gcc` if found, otherwise `cc`)
          C compiler to use for building the system.
  
  `-libs <extra libraries>`::         (default: none)
          Extra libraries to link with the system.
  
  `-no-curses`::
          Do not use the curses library.
  
  `-host <hosttype>`::                (default: determined automatically)
          The type of the host machine, in GNU's "configuration name" format
          (CPU-COMPANY-SYSTEM or CPU-COMPANY-KERNEL-SYSTEM).  This info is
          generally determined automatically by the `configure` script, and rarely
          ever needs to be provided by hand.  The installation instructions for
          GCC or GNU Emacs contain a complete list of configuration names.
  
  `-target <targettype>`::            (default: same as `-host`)
          The type of the target machine, in GNU's "configuration name" format
          (CPU-COMPANY-SYSTEM or CPU-COMPANY-KERNEL-SYSTEM). Setting this will
          setup OCaml as a cross-compiler which runs on `$host` and produces code
          for `$target`. This requires a C toolchain which also produces code for
          `$target` and a native OCaml compiler of the exact same version (if you
          want a cross 4.00.1, you need a native 4.00.1).
  
  `-x11include <include_dir>`::       (default: determined automatically)
  `-x11lib <lib_dir>`::               (default: determined automatically)
          Location of the X11 include directory (e.g. `/usr/X11R6/include`) and
          the X11 library directory (e.g. `/usr/X11R6/lib`).
  
  `-no-pthread`::
          Do not attempt to use POSIX threads.
  
  `-with-pthread`::
          Attempt to use POSIX threads (this is the default).
  
  `-no-shared-libs`::
          Do not configure support for shared libraries.
  
  `-dldefs <cpp flags>`::
  `-dllibs <flags and libraries>`::
          These options specify where to find the libraries for dynamic linking
          (i.e. use of shared libraries).  `-dldefs` specifies options for finding
          the header files, and `-dllibs` for finding the C libraries.
  
  `-as <assembler and options>`::     (default: determined automatically)
          The assembler to use for assembling ocamlopt-generated code.
  
  `-aspp <assembler and options>`::   (default: determined automatically)
          The assembler to use for assembling the parts of the run-time system
          manually written in assembly language. This assembler must pre-process
          its input with the C preprocessor.
  
  `-with-debug-runtime`::
          Compile and install the debug version of the runtimes, useful for
          debugging C stubs and other low-level code.
  
  `-with-instrumented-runtime`::
          Compile and install the instrumented version of the runtimes, useful
          mainly for fine-tuning the GC.  Works only on Linux.
  
  `-verbose`::
          Verbose output of the configuration tests.  Use it if the outcome of
          `configure` is not what you were expecting.
  
  `-no-debugger`::
          Do not build `ocamldebug`.
  
  `-no-native-compiler`::
          Do not build the native compiler -- bytecode compilation only.
  
  `-no-ocamldoc`::
          Do not build `ocamldoc`.
  
  `-no-ocamlbuild`::
          Deprecated since 4.03.0, as `ocamlbuild` is now distributed separately
          from the compiler distribution.
  
  `-no-graph`::
          Do not compile the Graphics library.
  
  `-partialld <linker and options>`:: (default: determined automatically)
          The linker and options to use for producing an object file (rather than
          an executable) from several other object files.
  
  `-no-cfi`::
          Do not compile support for CFI directives.
  +
  Examples:
  
  * Standard installation in `/usr/{bin,lib,man}` instead of `/usr/local`:
      ./configure -prefix /usr
  
  
  * Installation in `/usr`, man pages in section "l":
  
      ./configure -bindir /usr/bin -libdir /usr/lib/ocaml -mandir /usr/man/manl
  +
  