From: Helmut Grohne <helmut@subdivi.de>

Subject: make cross compilation work

This patch essentially replaces most AC_TRY_RUN with something "better".

Dependening on the use case that may be AC_TRY_COMPILE, AC_COMPUTE_INT or even

AC_CHECK_TYPE. Uses beyond cross compilation:

 * Significant simplification of the code.

 * Some checks become cacheable.

Index: expect-5.45/configure.in

===================================================================

--- expect-5.45.orig/configure.in

+++ expect-5.45/configure.in

@@ -467,47 +467,32 @@

 # and if so that WNOHANG is not defined.  The only place I've

 # seen this is ISC.

 AC_MSG_CHECKING([if WNOHANG requires _POSIX_SOURCE])

-AC_TRY_RUN([

+AC_TRY_COMPILE([

 #include <sys/wait.h>

-main() {

+],[

 #ifndef WNOHANG

-	return 0;

-#else

-	return 1;

+#error WNOHANG missing

 #endif

-}],

-	AC_MSG_RESULT(yes)

-	AC_DEFINE(WNOHANG_REQUIRES_POSIX_SOURCE)

-,

+],

 	AC_MSG_RESULT(no)

 ,

-	AC_MSG_ERROR([Expect can't be cross compiled])

+	AC_MSG_RESULT(yes)

+	AC_DEFINE(WNOHANG_REQUIRES_POSIX_SOURCE)

 )

 AC_MSG_CHECKING([if any value exists for WNOHANG])

 rm -rf wnohang

-AC_TRY_RUN([

+AC_COMPUTE_INT(WNOHANG_BACKUP_VALUE, WNOHANG, [

 #include <stdio.h>

 #include <sys/wait.h>

-main() {

-#ifdef WNOHANG

-	FILE *fp = fopen("wnohang","w");

-	fprintf(fp,"%d",WNOHANG);

-	fclose(fp);

-	return 0;

-#else

-	return 1;

-#endif

-}],

-	AC_MSG_RESULT(yes)

-	AC_DEFINE_UNQUOTED(WNOHANG_BACKUP_VALUE, `cat wnohang`)

-	rm -f wnohang

-,

-	AC_MSG_RESULT(no)

+],[WNOHANG_BACKUP_VALUE=no])

+if "$WNOHANG_BACKUP_VALUE" = "no"; then

 	AC_DEFINE(WNOHANG_BACKUP_VALUE, 1)

-,

-	AC_MSG_ERROR([Expect can't be cross compiled])

-)

+	AC_MSG_RESULT(no)

+else

+	AC_DEFINE_UNQUOTED(WNOHANG_BACKUP_VALUE, [$WNOHANG_BACKUP_VALUE])

+	AC_MSG_RESULT(yes)

+fi

 #

 # check how signals work

@@ -711,22 +696,12 @@

 fi

 # first check for the pure bsd

-AC_MSG_CHECKING([for struct sgttyb])

-AC_TRY_RUN([

-#include <sgtty.h>

-main()

-{

-  struct sgttyb tmp;

-  exit(0);

-}],

-        AC_MSG_RESULT(yes)

+AC_CHECK_TYPE([struct sgttyb],[

         AC_DEFINE(HAVE_SGTTYB)

         PTY_TYPE=sgttyb

-,

-        AC_MSG_RESULT(no)

-,

-	AC_MSG_ERROR([Expect can't be cross compiled])

-)

+],[],[

+#include <sgtty.h>

+])

 # mach systems have include files for unimplemented features

 # so avoid doing following test on those systems

@@ -736,109 +711,77 @@

   # note that if we detect termio.h (only), we still set PTY_TYPE=termios

   # since that just controls which of pty_XXXX.c file is use and

   # pty_termios.c is set up to handle pty_termio.

-  AC_MSG_CHECKING([for struct termio])

-  AC_TRY_RUN([#include <termio.h>

-  main()

-  {

-    struct termio tmp;

-    exit(0);

-  }],

+  AC_CHECK_TYPE([struct termio],[

         AC_DEFINE(HAVE_TERMIO)

         PTY_TYPE=termios

-        AC_MSG_RESULT(yes)

-,

-        AC_MSG_RESULT(no)

-,

-	AC_MSG_ERROR([Expect can't be cross compiled])

-)

+],[],[

+#include <termio.h>

+])

   # now check for the new style ttys (not yet posix)

-  AC_MSG_CHECKING([for struct termios])

-  AC_TRY_RUN([

+  AC_CHECK_TYPE([struct termios],[

+        AC_DEFINE(HAVE_TERMIOS)

+        PTY_TYPE=termios

+  ],[],[

   /* including termios.h on Solaris 5.6 fails unless inttypes.h included */

 #  ifdef HAVE_INTTYPES_H

 #  include <inttypes.h>

 #  endif

 #  include <termios.h>

-  main()

-  {

-    struct termios tmp;

-    exit(0);

-  }],

-        AC_DEFINE(HAVE_TERMIOS)

-        PTY_TYPE=termios

-        AC_MSG_RESULT(yes)

-  ,

-        AC_MSG_RESULT(no)

-  ,

-	AC_MSG_ERROR([Expect can't be cross compiled])

-  )

+  ])

 fi

 AC_MSG_CHECKING([if TCGETS or TCGETA in termios.h])

-AC_TRY_RUN([

+AC_TRY_COMPILE([

 /* including termios.h on Solaris 5.6 fails unless inttypes.h included */

 #ifdef HAVE_INTTYPES_H

 #include <inttypes.h>

 #endif

 #include <termios.h>

-main() {

+],[

 #if defined(TCGETS) || defined(TCGETA)

-	return 0;

 #else

-	return 1;

+#error missing

 #endif

-}],

+],[

 	AC_DEFINE(HAVE_TCGETS_OR_TCGETA_IN_TERMIOS_H)

 	AC_MSG_RESULT(yes)

-,

+],[

 	AC_MSG_RESULT(no)

-,

-	AC_MSG_ERROR([Expect can't be cross compiled])

-)

+])

 AC_MSG_CHECKING([if TIOCGWINSZ in termios.h])

-AC_TRY_RUN([

+AC_TRY_COMPILE([

 /* including termios.h on Solaris 5.6 fails unless inttypes.h included */

 #ifdef HAVE_INTTYPES_H

 #include <inttypes.h>

 #endif

 #include <termios.h>

-main() {

-#ifdef TIOCGWINSZ

-	return 0;

-#else

-	return 1;

+],[

+#ifndef TIOCGWINSZ

+#error missing

 #endif

-}],

+],[

 	AC_DEFINE(HAVE_TIOCGWINSZ_IN_TERMIOS_H)

 	AC_MSG_RESULT(yes)

-,

+],[

 	AC_MSG_RESULT(no)

-,

-	AC_MSG_ERROR([Expect can't be cross compiled])

-)

+])

 # finally check for Cray style ttys

 AC_MSG_CHECKING([for Cray-style ptys])

 SETUID=":"

-AC_TRY_RUN([

-main(){

-#ifdef CRAY

-	return 0;

-#else

-	return 1;

+AC_TRY_COMPILE([],[

+#ifndef CRAY

+#error missing

 #endif

-}

-],

+],[

 	PTY_TYPE=unicos

 	SETUID="chmod u+s"

 	AC_MSG_RESULT(yes)

-,

+],[

 	AC_MSG_RESULT(no)

-,

-	AC_MSG_ERROR([Expect can't be cross compiled])

-)

+])

 #

 # Check for select and/or poll. If both exist, we prefer select.

@@ -875,21 +818,16 @@

 # check for timezones

 #

 AC_MSG_CHECKING([for SV-style timezone])

-AC_TRY_RUN([

+AC_TRY_COMPILE([

 extern char *tzname[2];

 extern int daylight;

-main()

-{

+],[

   int *x = &daylight;

   char **y = tzname;

-

-  exit(0);

-}],

+],

 	AC_DEFINE(HAVE_SV_TIMEZONE)

 	AC_MSG_RESULT(yes),

 	AC_MSG_RESULT(no)

-,

-	AC_MSG_ERROR([Expect can't be cross compiled])

 )