C# support: remove pnet choice

[Bruno Haible]

Pnet development stopped in 2011 [1], and it was removed from Debian
in 2007 [2]. So, there is no point in supporting it any more in gnulib.

[1] https://git.savannah.gnu.org/gitweb/?p=dotgnu-pnet.git;a=shortlog
[2] https://packages.qa.debian.org/p/pnet.html


2018-10-08  Bruno Haible  <address@hidden>

        csharpcomp*, csharpexec*: Remove support for pnet.
        * m4/csharpcomp.m4 (gt_CSHARPCOMP): Don't test for cscc. Don't set
        HAVE_CSCC.
        * build-aux/csharpcomp.sh.in (options_cscc): Remove variable.
        Don't test HAVE_CSCC.
        * lib/csharpcomp.c (compile_csharp_using_pnet): Remove function.
        (compile_csharp_class): Don't invoke it.
        * m4/csharpexec.m4 (gt_CSHARPEXEC): Don't test for ilrun. Don't set
        HAVE_ILRUN.
        * build-aux/csharpexec.sh.in (options_ilrun): Remove variable.
        Don't test HAVE_ILRUN.
        * lib/csharpexec.c (execute_csharp_using_pnet): Remove function.
        (execute_csharp_program): Don't invoke it.
        * m4/csharp.m4 (gt_CSHARP_CHOICE): Don't recognize --enable-csharp=pnet
        any more.

diff --git a/build-aux/csharpcomp.sh.in b/build-aux/csharpcomp.sh.in
index a68ddcf..19c56dd 100644
--- a/build-aux/csharpcomp.sh.in
+++ b/build-aux/csharpcomp.sh.in
@@ -65,7 +65,6 @@ func_tmpdir ()
 }
 
 sed_quote_subst='s/\([|&;<>()$`"'"'"'*?[#~=%   \\]\)/\\\1/g'
-options_cscc=
 options_mcs=
 options_csc="-nologo"
 sources=
@@ -74,7 +73,6 @@ while test $# != 0; do
     -o)
       case "$2" in
         *.dll)
-          options_cscc="$options_cscc -shared"
           options_mcs="$options_mcs -target:library"
           options_csc="$options_csc -target:library"
           ;;
@@ -82,29 +80,24 @@ while test $# != 0; do
           options_csc="$options_csc -target:exe"
           ;;
       esac
-      options_cscc="$options_cscc -o "`echo "$2" | sed -e "$sed_quote_subst"`
       options_mcs="$options_mcs -out:"`echo "$2" | sed -e "$sed_quote_subst"`
       options_csc="$options_csc -out:"`echo "$2" | sed -e "$sed_quote_subst"`
       shift
       ;;
     -L)
-      options_cscc="$options_cscc -L "`echo "$2" | sed -e "$sed_quote_subst"`
       options_mcs="$options_mcs -lib:"`echo "$2" | sed -e "$sed_quote_subst"`
       options_csc="$options_csc -lib:"`echo "$2" | sed -e "$sed_quote_subst"`
       shift
       ;;
     -l)
-      options_cscc="$options_cscc -l "`echo "$2" | sed -e "$sed_quote_subst"`
       options_mcs="$options_mcs -reference:"`echo "$2" | sed -e 
"$sed_quote_subst"`
       options_csc="$options_csc -reference:"`echo "$2" | sed -e 
"$sed_quote_subst"`".dll"
       shift
       ;;
     -O)
-      options_cscc="$options_cscc -O"
       options_csc="$options_csc -optimize+"
       ;;
     -g)
-      options_cscc="$options_cscc -g"
       options_mcs="$options_mcs -debug"
       options_csc="$options_csc -debug+"
       ;;
@@ -113,7 +106,6 @@ while test $# != 0; do
       exit 1
       ;;
     *.resources)
-      options_cscc="$options_cscc -fresources="`echo "$1" | sed -e 
"$sed_quote_subst"`
       options_mcs="$options_mcs -resource:"`echo "$1" | sed -e 
"$sed_quote_subst"`
       options_csc="$options_csc -resource:"`echo "$1" | sed -e 
"$sed_quote_subst"`
       ;;
@@ -128,31 +120,26 @@ while test $# != 0; do
   shift
 done
 
-if test -n "@HAVE_CSCC@"; then
-  test -z "$CSHARP_VERBOSE" || echo cscc $options_cscc $sources
-  exec cscc $options_cscc $sources
-else
-  if test -n "@HAVE_MCS@"; then
-    # mcs prints it errors and warnings to stdout, not stderr. Furthermore it
-    # adds a useless line "Compilation succeeded..." at the end. Correct both.
-    sed_drop_success_line='${
+if test -n "@HAVE_MCS@"; then
+  # mcs prints it errors and warnings to stdout, not stderr. Furthermore it
+  # adds a useless line "Compilation succeeded..." at the end. Correct both.
+  sed_drop_success_line='${
 /^Compilation succeeded/d
 }'
-    func_tmpdir
-    trap 'rm -rf "$tmp"' 1 2 3 15
-    test -z "$CSHARP_VERBOSE" || echo mcs $options_mcs $sources
-    mcs $options_mcs $sources > "$tmp"/mcs.err
-    result=$?
-    sed -e "$sed_drop_success_line" < "$tmp"/mcs.err >&2
-    rm -rf "$tmp"
-    exit $result
+  func_tmpdir
+  trap 'rm -rf "$tmp"' 1 2 3 15
+  test -z "$CSHARP_VERBOSE" || echo mcs $options_mcs $sources
+  mcs $options_mcs $sources > "$tmp"/mcs.err
+  result=$?
+  sed -e "$sed_drop_success_line" < "$tmp"/mcs.err >&2
+  rm -rf "$tmp"
+  exit $result
+else
+  if test -n "@HAVE_CSC@"; then
+    test -z "$CSHARP_VERBOSE" || echo csc $options_csc $sources
+    exec csc $options_csc $sources
   else
-    if test -n "@HAVE_CSC@"; then
-      test -z "$CSHARP_VERBOSE" || echo csc $options_csc $sources
-      exec csc $options_csc $sources
-    else
-      echo 'C# compiler not found, try installing pnet, then reconfigure' 1>&2
-      exit 1
-    fi
+    echo 'C# compiler not found, try installing mono, then reconfigure' 1>&2
+    exit 1
   fi
 fi
diff --git a/build-aux/csharpexec.sh.in b/build-aux/csharpexec.sh.in
index 436b860..812cdc6 100644
--- a/build-aux/csharpexec.sh.in
+++ b/build-aux/csharpexec.sh.in
@@ -29,13 +29,11 @@
 #   -L DIRECTORY      search for C# libraries also in DIRECTORY
 
 sed_quote_subst='s/\([|&;<>()$`"'"'"'*?[#~=%   \\]\)/\\\1/g'
-options_ilrun=
 libdirs_mono=
 prog=
 while test $# != 0; do
   case "$1" in
     -L)
-      options_ilrun="$options_ilrun -L "`echo "$2" | sed -e "$sed_quote_subst"`
       libdirs_mono="${libdirs_mono:address@hidden@}$2"
       shift
       ;;
@@ -62,34 +60,29 @@ case "$prog" in
     ;;
 esac
 
-if test -n "@HAVE_ILRUN@"; then
-  test -z "$CSHARP_VERBOSE" || echo ilrun $options_ilrun "$@"
-  exec ilrun $options_ilrun "$@"
+if test -n "@HAVE_MONO@"; then
+  CONF_MONO_PATH='@MONO_PATH@'
+  if test -n "$libdirs_mono"; then
+    MONO_PATH="$libdirs_mono${CONF_MONO_PATH:address@hidden@$CONF_MONO_PATH}"
+  else
+    MONO_PATH="$CONF_MONO_PATH"
+  fi
+  export MONO_PATH
+  test -z "$CSHARP_VERBOSE" || echo mono "$@"
+  exec mono "$@"
 else
-  if test -n "@HAVE_MONO@"; then
-    CONF_MONO_PATH='@MONO_PATH@'
+  if test -n "@HAVE_CLIX@"; then
+    CONF_CLIX_PATH='@CLIX_PATH@'
     if test -n "$libdirs_mono"; then
-      MONO_PATH="$libdirs_mono${CONF_MONO_PATH:address@hidden@$CONF_MONO_PATH}"
+      
@address@hidden"$libdirs_mono${CONF_CLIX_PATH:address@hidden@$CONF_CLIX_PATH}"
     else
-      MONO_PATH="$CONF_MONO_PATH"
+      @address@hidden"$CONF_CLIX_PATH"
     fi
-    export MONO_PATH
-    test -z "$CSHARP_VERBOSE" || echo mono "$@"
-    exec mono "$@"
+    export @CLIX_PATH_VAR@
+    test -z "$CSHARP_VERBOSE" || echo clix "$@"
+    exec clix "$@"
   else
-    if test -n "@HAVE_CLIX@"; then
-      CONF_CLIX_PATH='@CLIX_PATH@'
-      if test -n "$libdirs_mono"; then
-        
@address@hidden"$libdirs_mono${CONF_CLIX_PATH:address@hidden@$CONF_CLIX_PATH}"
-      else
-        @address@hidden"$CONF_CLIX_PATH"
-      fi
-      export @CLIX_PATH_VAR@
-      test -z "$CSHARP_VERBOSE" || echo clix "$@"
-      exec clix "$@"
-    else
-      echo 'C# virtual machine not found, try installing pnet, then 
reconfigure' 1>&2
-      exit 1
-    fi
+    echo 'C# virtual machine not found, try installing mono, then reconfigure' 
1>&2
+    exit 1
   fi
 fi
diff --git a/lib/csharpcomp.c b/lib/csharpcomp.c
index d694401..9d6593f 100644
--- a/lib/csharpcomp.c
+++ b/lib/csharpcomp.c
@@ -42,129 +42,21 @@
 
    Program    from
 
-   cscc       pnet
    mcs        mono
    csc        sscli
 
    We try the CIL interpreters in the following order:
-     1. "cscc", because it is a completely free system.
-     2. "mcs", because it is a free system but doesn't integrate so well
+     1. "mcs", because it is a free system but doesn't integrate so well
         with Unix. (Command line options start with / instead of -. Errors go
         to stdout instead of stderr. Source references are printed as
         "file(lineno)" instead of "file:lineno:".)
-     3. "csc", although it is not free, because it is a kind of "reference
+     2. "csc", although it is not free, because it is a kind of "reference
         implementation" of C#.
    But the order can be changed through the --enable-csharp configuration
    option.
  */
 
 static int
-compile_csharp_using_pnet (const char * const *sources,
-                           unsigned int sources_count,
-                           const char * const *libdirs,
-                           unsigned int libdirs_count,
-                           const char * const *libraries,
-                           unsigned int libraries_count,
-                           const char *output_file, bool output_is_library,
-                           bool optimize, bool debug,
-                           bool verbose)
-{
-  static bool cscc_tested;
-  static bool cscc_present;
-
-  if (!cscc_tested)
-    {
-      /* Test for presence of cscc:
-         "cscc --version >/dev/null 2>/dev/null"  */
-      char *argv[3];
-      int exitstatus;
-
-      argv[0] = "cscc";
-      argv[1] = "--version";
-      argv[2] = NULL;
-      exitstatus = execute ("cscc", "cscc", argv, false, false, true, true,
-                            true, false, NULL);
-      cscc_present = (exitstatus == 0);
-      cscc_tested = true;
-    }
-
-  if (cscc_present)
-    {
-      unsigned int argc;
-      char **argv;
-      char **argp;
-      int exitstatus;
-      unsigned int i;
-
-      argc =
-        1 + (output_is_library ? 1 : 0) + 2 + 2 * libdirs_count
-        + 2 * libraries_count + (optimize ? 1 : 0) + (debug ? 1 : 0)
-        + sources_count;
-      argv = (char **) xmalloca ((argc + 1) * sizeof (char *));
-
-      argp = argv;
-      *argp++ = "cscc";
-      if (output_is_library)
-        *argp++ = "-shared";
-      *argp++ = "-o";
-      *argp++ = (char *) output_file;
-      for (i = 0; i < libdirs_count; i++)
-        {
-          *argp++ = "-L";
-          *argp++ = (char *) libdirs[i];
-        }
-      for (i = 0; i < libraries_count; i++)
-        {
-          *argp++ = "-l";
-          *argp++ = (char *) libraries[i];
-        }
-      if (optimize)
-        *argp++ = "-O";
-      if (debug)
-        *argp++ = "-g";
-      for (i = 0; i < sources_count; i++)
-        {
-          const char *source_file = sources[i];
-          if (strlen (source_file) >= 10
-              && memcmp (source_file + strlen (source_file) - 10, ".resources",
-                         10) == 0)
-            {
-              char *option = (char *) xmalloca (12 + strlen (source_file) + 1);
-
-              memcpy (option, "-fresources=", 12);
-              strcpy (option + 12, source_file);
-              *argp++ = option;
-            }
-          else
-            *argp++ = (char *) source_file;
-        }
-      *argp = NULL;
-      /* Ensure argv length was correctly calculated.  */
-      if (argp - argv != argc)
-        abort ();
-
-      if (verbose)
-        {
-          char *command = shell_quote_argv (argv);
-          printf ("%s\n", command);
-          free (command);
-        }
-
-      exitstatus = execute ("cscc", "cscc", argv, false, false, false, false,
-                            true, true, NULL);
-
-      for (i = 0; i < sources_count; i++)
-        if (argv[argc - sources_count + i] != sources[i])
-          freea (argv[argc - sources_count + i]);
-      freea (argv);
-
-      return (exitstatus != 0);
-    }
-  else
-    return -1;
-}
-
-static int
 compile_csharp_using_mono (const char * const *sources,
                            unsigned int sources_count,
                            const char * const *libdirs,
@@ -519,16 +411,6 @@ compile_csharp_class (const char * const *sources,
   int result;
 
   /* First try the C# implementation specified through --enable-csharp.  */
-#if CSHARP_CHOICE_PNET
-  result = compile_csharp_using_pnet (sources, sources_count,
-                                      libdirs, libdirs_count,
-                                      libraries, libraries_count,
-                                      output_file, output_is_library,
-                                      optimize, debug, verbose);
-  if (result >= 0)
-    return (bool) result;
-#endif
-
 #if CSHARP_CHOICE_MONO
   result = compile_csharp_using_mono (sources, sources_count,
                                       libdirs, libdirs_count,
@@ -540,16 +422,6 @@ compile_csharp_class (const char * const *sources,
 #endif
 
   /* Then try the remaining C# implementations in our standard order.  */
-#if !CSHARP_CHOICE_PNET
-  result = compile_csharp_using_pnet (sources, sources_count,
-                                      libdirs, libdirs_count,
-                                      libraries, libraries_count,
-                                      output_file, output_is_library,
-                                      optimize, debug, verbose);
-  if (result >= 0)
-    return (bool) result;
-#endif
-
 #if !CSHARP_CHOICE_MONO
   result = compile_csharp_using_mono (sources, sources_count,
                                       libdirs, libdirs_count,
@@ -568,6 +440,6 @@ compile_csharp_class (const char * const *sources,
   if (result >= 0)
     return (bool) result;
 
-  error (0, 0, _("C# compiler not found, try installing pnet"));
+  error (0, 0, _("C# compiler not found, try installing mono"));
   return true;
 }
diff --git a/lib/csharpexec.c b/lib/csharpexec.c
index 54b81d0..525e424 100644
--- a/lib/csharpexec.c
+++ b/lib/csharpexec.c
@@ -70,7 +70,6 @@
 
    Program    from
 
-   ilrun      pnet
    mono       mono
    clix       sscli
 
@@ -78,86 +77,15 @@
    Windows: semicolon separated list of pathnames.)
 
    We try the CIL interpreters in the following order:
-     1. "ilrun", because it is a completely free system.
-     2. "mono", because it is a partially free system but doesn't integrate
+     1. "mono", because it is a partially free system but doesn't integrate
         well with Unix.
-     3. "clix", although it is not free, because it is a kind of "reference
+     2. "clix", although it is not free, because it is a kind of "reference
         implementation" of C#.
    But the order can be changed through the --enable-csharp configuration
    option.
  */
 
 static int
-execute_csharp_using_pnet (const char *assembly_path,
-                           const char * const *libdirs,
-                           unsigned int libdirs_count,
-                           const char * const *args, unsigned int nargs,
-                           bool verbose, bool quiet,
-                           execute_fn *executer, void *private_data)
-{
-  static bool ilrun_tested;
-  static bool ilrun_present;
-
-  if (!ilrun_tested)
-    {
-      /* Test for presence of ilrun:
-         "ilrun --version >/dev/null 2>/dev/null"  */
-      char *argv[3];
-      int exitstatus;
-
-      argv[0] = "ilrun";
-      argv[1] = "--version";
-      argv[2] = NULL;
-      exitstatus = execute ("ilrun", "ilrun", argv, false, false, true, true,
-                            true, false, NULL);
-      ilrun_present = (exitstatus == 0);
-      ilrun_tested = true;
-    }
-
-  if (ilrun_present)
-    {
-      unsigned int argc;
-      char **argv;
-      char **argp;
-      unsigned int i;
-      bool err;
-
-      argc = 1 + 2 * libdirs_count + 1 + nargs;
-      argv = (char **) xmalloca ((argc + 1) * sizeof (char *));
-
-      argp = argv;
-      *argp++ = "ilrun";
-      for (i = 0; i < libdirs_count; i++)
-        {
-          *argp++ = "-L";
-          *argp++ = (char *) libdirs[i];
-        }
-      *argp++ = (char *) assembly_path;
-      for (i = 0; i < nargs; i++)
-        *argp++ = (char *) args[i];
-      *argp = NULL;
-      /* Ensure argv length was correctly calculated.  */
-      if (argp - argv != argc)
-        abort ();
-
-      if (verbose)
-        {
-          char *command = shell_quote_argv (argv);
-          printf ("%s\n", command);
-          free (command);
-        }
-
-      err = executer ("ilrun", "ilrun", argv, private_data);
-
-      freea (argv);
-
-      return err;
-    }
-  else
-    return -1;
-}
-
-static int
 execute_csharp_using_mono (const char *assembly_path,
                            const char * const *libdirs,
                            unsigned int libdirs_count,
@@ -300,14 +228,6 @@ execute_csharp_program (const char *assembly_path,
   }
 
   /* First try the C# implementation specified through --enable-csharp.  */
-#if CSHARP_CHOICE_PNET
-  result = execute_csharp_using_pnet (assembly_path, libdirs, libdirs_count,
-                                      args, nargs, verbose, quiet,
-                                      executer, private_data);
-  if (result >= 0)
-    return (bool) result;
-#endif
-
 #if CSHARP_CHOICE_MONO
   result = execute_csharp_using_mono (assembly_path, libdirs, libdirs_count,
                                       args, nargs, verbose, quiet,
@@ -317,14 +237,6 @@ execute_csharp_program (const char *assembly_path,
 #endif
 
   /* Then try the remaining C# implementations in our standard order.  */
-#if !CSHARP_CHOICE_PNET
-  result = execute_csharp_using_pnet (assembly_path, libdirs, libdirs_count,
-                                      args, nargs, verbose, quiet,
-                                      executer, private_data);
-  if (result >= 0)
-    return (bool) result;
-#endif
-
 #if !CSHARP_CHOICE_MONO
   result = execute_csharp_using_mono (assembly_path, libdirs, libdirs_count,
                                       args, nargs, verbose, quiet,
@@ -340,6 +252,6 @@ execute_csharp_program (const char *assembly_path,
     return (bool) result;
 
   if (!quiet)
-    error (0, 0, _("C# virtual machine not found, try installing pnet"));
+    error (0, 0, _("C# virtual machine not found, try installing mono"));
   return true;
 }
diff --git a/m4/csharp.m4 b/m4/csharp.m4
index d9c5931..a21a3f7 100644
--- a/m4/csharp.m4
+++ b/m4/csharp.m4
@@ -1,25 +1,21 @@
-# csharp.m4 serial 3
+# csharp.m4 serial 4
 dnl Copyright (C) 2004-2005, 2009-2018 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
 # Sets CSHARP_CHOICE to the preferred C# implementation:
-# 'pnet' or 'mono' or 'any' or 'no'.
+# 'mono' or 'any' or 'no'.
 AC_DEFUN([gt_CSHARP_CHOICE],
 [
   AC_MSG_CHECKING([for preferred C[#] implementation])
   AC_ARG_ENABLE([csharp],
-    [  --enable-csharp[[=IMPL]]  choose preferred C[#] implementation (pnet or 
mono)],
+    [  --enable-csharp[[=IMPL]]  choose preferred C[#] implementation (mono)],
     [CSHARP_CHOICE="$enableval"],
     CSHARP_CHOICE=any)
   AC_SUBST([CSHARP_CHOICE])
   AC_MSG_RESULT([$CSHARP_CHOICE])
   case "$CSHARP_CHOICE" in
-    pnet)
-      AC_DEFINE([CSHARP_CHOICE_PNET], [1],
-        [Define if pnet is the preferred C# implementation.])
-      ;;
     mono)
       AC_DEFINE([CSHARP_CHOICE_MONO], [1],
         [Define if mono is the preferred C# implementation.])
diff --git a/m4/csharpcomp.m4 b/m4/csharpcomp.m4
index a2aab06..cd816ca 100644
--- a/m4/csharpcomp.m4
+++ b/m4/csharpcomp.m4
@@ -1,4 +1,4 @@
-# csharpcomp.m4 serial 8
+# csharpcomp.m4 serial 9
 dnl Copyright (C) 2003-2005, 2007, 2009-2018 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -6,7 +6,7 @@ dnl with or without modifications, as long as this notice is 
preserved.
 
 # Prerequisites of csharpcomp.sh.
 # Checks for a C# compiler.
-# Sets at most one of HAVE_CSCC, HAVE_MCS, HAVE_CSC.
+# Sets at most one of HAVE_MCS, HAVE_CSC.
 # Sets HAVE_CSHARPCOMP to nonempty if csharpcomp.sh will work.
 # Also sets CSHARPCOMPFLAGS.
 AC_DEFUN([gt_CSHARPCOMP],
@@ -17,30 +17,13 @@ AC_DEFUN([gt_CSHARPCOMP],
   pushdef([AC_MSG_CHECKING],[:])dnl
   pushdef([AC_CHECKING],[:])dnl
   pushdef([AC_MSG_RESULT],[:])dnl
-  AC_CHECK_PROG([HAVE_CSCC_IN_PATH], [cscc], [yes])
   AC_CHECK_PROG([HAVE_MCS_IN_PATH], [mcs], [yes])
   AC_CHECK_PROG([HAVE_CSC_IN_PATH], [csc], [yes])
   popdef([AC_MSG_RESULT])dnl
   popdef([AC_CHECKING])dnl
   popdef([AC_MSG_CHECKING])dnl
-  for impl in "$CSHARP_CHOICE" pnet mono sscli no; do
+  for impl in "$CSHARP_CHOICE" mono sscli no; do
     case "$impl" in
-      pnet)
-        if test -n "$HAVE_CSCC_IN_PATH" \
-           && cscc --version >/dev/null 2>/dev/null \
-           && (
-             # See if pnetlib is well installed.
-             echo 'class ConfTest { static void Main() { } }' > conftest.cs
-             cscc -o conftest.exe conftest.cs 2>/dev/null
-             error=$?
-             rm -f conftest.cs conftest.exe
-             exit $error
-            ); then
-          HAVE_CSCC=1
-          ac_result="cscc"
-          break
-        fi
-        ;;
       mono)
         if test -n "$HAVE_MCS_IN_PATH" \
            && mcs --version >/dev/null 2>/dev/null \
@@ -67,7 +50,6 @@ AC_DEFUN([gt_CSHARPCOMP],
     esac
   done
   AC_MSG_RESULT([$ac_result])
-  AC_SUBST([HAVE_CSCC])
   AC_SUBST([HAVE_MCS])
   AC_SUBST([HAVE_CSC])
   dnl Provide a default for CSHARPCOMPFLAGS.
diff --git a/m4/csharpexec.m4 b/m4/csharpexec.m4
index f645ffd..f600148 100644
--- a/m4/csharpexec.m4
+++ b/m4/csharpexec.m4
@@ -1,4 +1,4 @@
-# csharpexec.m4 serial 6
+# csharpexec.m4 serial 7
 dnl Copyright (C) 2003-2005, 2009-2018 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -7,7 +7,7 @@ dnl with or without modifications, as long as this notice is 
preserved.
 # Prerequisites of csharpexec.sh.
 # Checks for a C# execution engine.
 # gt_CSHARPEXEC or gt_CSHARPEXEC(testexecutable, its-directory)
-# Sets at most one of HAVE_ILRUN, HAVE_MONO, HAVE_CLIX.
+# Sets at most one of HAVE_MONO, HAVE_CLIX.
 # Sets HAVE_CSHARPEXEC to nonempty if csharpexec.sh will work.
 AC_DEFUN([gt_CSHARPEXEC],
 [
@@ -23,23 +23,13 @@ AC_DEFUN([gt_CSHARPEXEC],
   pushdef([AC_MSG_CHECKING],[:])dnl
   pushdef([AC_CHECKING],[:])dnl
   pushdef([AC_MSG_RESULT],[:])dnl
-  AC_CHECK_PROG([HAVE_ILRUN_IN_PATH], [ilrun], [yes])
   AC_CHECK_PROG([HAVE_MONO_IN_PATH], [mono], [yes])
   AC_CHECK_PROG([HAVE_CLIX_IN_PATH], [clix], [yes])
   popdef([AC_MSG_RESULT])dnl
   popdef([AC_CHECKING])dnl
   popdef([AC_MSG_CHECKING])dnl
-  for impl in "$CSHARP_CHOICE" pnet mono no; do
+  for impl in "$CSHARP_CHOICE" mono no; do
     case "$impl" in
-      pnet)
-        if test -n "$HAVE_ILRUN_IN_PATH" \
-           && ilrun --version >/dev/null 2>/dev/null \
-           ifelse([$1], , , [&& ilrun $2/$1 >/dev/null 2>/dev/null]); then
-          HAVE_ILRUN=1
-          ac_result="ilrun"
-          break
-        fi
-        ;;
       mono)
         if test -n "$HAVE_MONO_IN_PATH" \
            && mono --version >/dev/null 2>/dev/null \
@@ -81,7 +71,6 @@ AC_DEFUN([gt_CSHARPEXEC],
   AC_SUBST([MONO_PATH_SEPARATOR])
   AC_SUBST([CLIX_PATH_VAR])
   AC_SUBST([CLIX_PATH])
-  AC_SUBST([HAVE_ILRUN])
   AC_SUBST([HAVE_MONO])
   AC_SUBST([HAVE_CLIX])
 ])