OTP-8323 Miscellaneous cross compilation improvements. For example, one

          new mandatory configuration variable that replaces all other
          previously mandatory configuration variables, and better
          documentation. Note that old cross compilation configurations
          cannot be used without modifications.

          For more information see the $ERL_TOP/xcomp/README file.

3 files changed, 202 insertions, 135 deletions

diff --git a/erts/aclocal.m4 b/erts/aclocal.m4
index 0ad963db12..e9a0cc228f 100644
--- a/erts/aclocal.m4
+++ b/erts/aclocal.m4
@@ -1,4 +1,4 @@
-
+dnl
 dnl %CopyrightBegin%
 dnl 
 dnl Copyright Ericsson AB 1998-2009. All Rights Reserved.
@@ -15,6 +15,7 @@ dnl the License for the specific language governing rights and limitations
 dnl under the License.
 dnl 
 dnl %CopyrightEnd%
+dnl
 
 dnl
 dnl aclocal.m4
@@ -519,46 +520,79 @@ dnl On ofs1 the '-pthread' switch should be used
 		ETHR_DEFS="$ETHR_DEFS -D_POSIX_PTHREAD_SEMANTICS" ;;
 	    linux*)
 		ETHR_DEFS="$ETHR_DEFS -D_POSIX_THREAD_SAFE_FUNCTIONS -D_GNU_SOURCE"
-		if test "x$erl_xcomp_linux_kernel" != "x"; then
-		    linux_kernel_vsn_=$erl_xcomp_linux_kernel
-		else
-		    linux_kernel_vsn_=`uname -r`
-		fi
-		usable_sigusrx=no
-		usable_sigaltstack=no
 
-		# FIXME: Test for actual problems instead of kernel versions.
-		case $linux_kernel_vsn_ in
-		    [[0-1]].*|2.[[0-1]]|2.[[0-1]].*)
-			;;
-		    2.[[2-3]]|2.[[2-3]].*)
-			usable_sigusrx=yes
-			;;
-		    *)
+		if test	X$cross_compiling = Xyes; then
+		    if test "X$erl_xcomp_linux_usable_sigusrx" = "X"; then
 			usable_sigusrx=yes
+			usable_sigusrx_guessed=yes
+		    else
+			usable_sigusrx=$erl_xcomp_linux_usable_sigusrx
+			usable_sigusrx_guessed=no
+		    fi
+		    if test "X$erl_xcomp_linux_usable_sigaltstack" = "X"; then
 			usable_sigaltstack=yes
-			;;
-		esac
+			usable_sigaltstack_guessed=yes
+		    else
+			usable_sigaltstack=$erl_xcomp_linux_usable_sigaltstack
+			usable_sigaltstack_guessed=no
+		    fi
+		else
+		    # FIXME: Test for actual problems instead of kernel versions
+		    linux_kernel_vsn_=`uname -r`
+		    case $linux_kernel_vsn_ in
+			[[0-1]].*|2.[[0-1]]|2.[[0-1]].*)
+			    usable_sigusrx=no
+			    usable_sigaltstack=no;;
+			2.[[2-3]]|2.[[2-3]].*)
+			    usable_sigusrx=yes
+			    usable_sigaltstack=no;;
+		    	*)
+			    usable_sigusrx=yes
+			    usable_sigaltstack=yes;;
+		    esac
+		    usable_sigusrx_guessed=no
+		    usable_sigaltstack_guessed=no
+		fi
 
 		AC_MSG_CHECKING(if SIGUSR1 and SIGUSR2 can be used)
 		AC_MSG_RESULT($usable_sigusrx)
+		if test $usable_sigusrx_guessed = yes; then
+		    AC_MSG_WARN([result $usable_sigusrx guessed because of cross compilation])
+		fi
 		if test $usable_sigusrx = no; then
 		    ETHR_DEFS="$ETHR_DEFS -DETHR_UNUSABLE_SIGUSRX"
 		fi
 
 		AC_MSG_CHECKING(if sigaltstack can be used)
 		AC_MSG_RESULT($usable_sigaltstack)
+		if test $usable_sigaltstack_guessed = yes; then
+		    AC_MSG_WARN([result $usable_sigaltstack guessed because of cross compilation])
+		fi
 		if test $usable_sigaltstack = no; then
 		    ETHR_DEFS="$ETHR_DEFS -DETHR_UNUSABLE_SIGALTSTACK"
 		fi
 
 		AC_MSG_CHECKING(for Native POSIX Thread Library)
-		case `getconf GNU_LIBPTHREAD_VERSION 2>/dev/null` in
-		    nptl*) nptl=yes;;
-		    NPTL*) nptl=yes;;
-		    *)  nptl=no;;
-		esac
+		if test	X$cross_compiling = Xyes; then
+		    if test "X$erl_xcomp_linux_nptl" = "X"; then
+			nptl=yes
+			nptl_guessed=yes
+		    else
+			nptl=$erl_xcomp_linux_nptl
+			nptl_guessed=no
+		    fi
+		else
+		    case `getconf GNU_LIBPTHREAD_VERSION 2>/dev/null` in
+			nptl*) nptl=yes;;
+			NPTL*) nptl=yes;;
+			*)  nptl=no;;
+		    esac
+		    nptl_guessed=no
+		fi
 		AC_MSG_RESULT($nptl)
+		if test $nptl_guessed = yes; then
+		    AC_MSG_WARN([result $nptl guessed because of cross compilation])
+		fi
 		if test $nptl = yes; then
 		    ETHR_THR_LIB_BASE_NAME=nptl
 		fi
@@ -567,7 +601,10 @@ dnl On ofs1 the '-pthread' switch should be used
 		    AC_CHECK_HEADER(nptl/pthread.h, need_nptl_incldir=yes)
 		    if test $need_nptl_incldir = yes; then
 			# Ahh...
-			nptl_path="$C_INCLUDE_PATH:$CPATH:/usr/local/include:/usr/include"
+			nptl_path="$C_INCLUDE_PATH:$CPATH"
+			if test X$cross_compiling != Xyes; then
+			    nptl_path="$nptl_path:/usr/local/include:/usr/include"
+			fi
 			nptl_ws_path=
 			save_ifs="$IFS"; IFS=":"
 			for dir in $nptl_path; do
@@ -683,7 +720,7 @@ if test "x$ETHR_THR_LIB_BASE" != "x"; then
 	ETHR_LIB_NAME=$ethr_lib_name
 fi
 
-AC_CHECK_SIZEOF(void *, 4)
+AC_CHECK_SIZEOF(void *)
 AC_DEFINE_UNQUOTED(ETHR_SIZEOF_PTR, $ac_cv_sizeof_void_p, [Define to the size of pointers])
 
 if test "X$disable_native_ethr_impls" = "Xyes"; then
@@ -751,13 +788,21 @@ case $clock_gettime_correction in
 			case $clock_gettime_correction in
 			    unknown)
 				if test x$clock_gettime_compiles = xyes; then
-				    linux_kernel_vsn_=`uname -r`
-				    case $linux_kernel_vsn_ in
-					[[0-1]].*|2.[[0-5]]|2.[[0-5]].*)
-					    erl_cv_time_correction=times ;;
-					*)
-					    erl_cv_time_correction=clock_gettime;;
-				    esac
+				    if test X$cross_compiling != Xyes; then
+					if test "X$erl_xcomp_linux_clock_gettime_correction" = "Xno"; then
+					    erl_cv_time_correction=times
+					else
+					    erl_cv_time_correction=clock_gettime
+					fi
+				    else
+				    	linux_kernel_vsn_=`uname -r`
+				    	case $linux_kernel_vsn_ in
+					    [[0-1]].*|2.[[0-5]]|2.[[0-5]].*)
+					    	erl_cv_time_correction=times ;;
+					    *)
+					    	erl_cv_time_correction=clock_gettime;;
+				    	esac
+				    fi
 				else
 				    erl_cv_time_correction=times
 				fi
@@ -774,6 +819,7 @@ case $clock_gettime_correction in
 	;;
 esac
 ])
+
 xrtlib=""
 case $erl_cv_time_correction in
   times)
@@ -781,6 +827,9 @@ case $erl_cv_time_correction in
 	[Define if you do not have a high-res. timer & want to use times() instead])
     ;;
   clock_gettime)
+    if test X$cross_compiling = Xyes -a X$erl_xcomp_linux_clock_gettime_correction = X; then
+	AC_MSG_WARN([result clock_gettime guessed because of cross compilation])
+    fi
     xrtlib="-lrt"
     AC_DEFINE(GETHRTIME_WITH_CLOCK_GETTIME,[1],
 	[Define if you want to use clock_gettime to simulate gethrtime])
@@ -840,7 +889,15 @@ int main() {
 	exit(5);
     exit(0); return 0;
 }
-], erl_gethrvtime=procfs_ioctl, erl_gethrvtime=false, erl_gethrvtime=false)
+],
+erl_gethrvtime=procfs_ioctl,
+erl_gethrvtime=false,
+if test "x$erl_xcomp_gethrvtime_procfs_ioctl" = "xyes"; then
+	erl_gethrvtime=procfs_ioctl
+else
+	erl_gethrvtime=false
+fi)
+
 case $erl_gethrvtime in
   procfs_ioctl)
 	AC_DEFINE(HAVE_GETHRVTIME_PROCFS_IOCTL,[1],
@@ -880,7 +937,14 @@ case $erl_gethrvtime in
 	      exit(5);
 	    exit(0); return 0;
 	  }
-	], erl_clock_gettime=true, erl_clock_gettime=false, erl_clock_gettime=false)
+	],
+	erl_clock_gettime=true,
+	erl_clock_gettime=false,
+	if test "x$erl_xcomp_clock_gettime" = "xyes"; then
+		erl_clock_gettime=true
+	else
+		erl_clock_gettime=false
+	fi)
 	LIBS=$save_libs
 	case $host_os in
 		linux*)
diff --git a/erts/configure.in b/erts/configure.in
index 895a357023..faccf5f102 100644
--- a/erts/configure.in
+++ b/erts/configure.in
@@ -94,13 +94,6 @@ enable_child_waiter_thread=no
 ENABLE_ALLOC_TYPE_VARS=
 AC_SUBST(ENABLE_ALLOC_TYPE_VARS)
 
-AC_ARG_WITH(xcomp-conf,
-[  --with-xcompconf=PATH     path to cross compilation configuration])
-if test "x$with_xcompconf" != "xno" -a "x$with_xcompconf" != "x" ; then
-    . $with_xcompconf
-fi
-
-
 AC_ARG_ENABLE(threads,
 [  --enable-threads        enable async thread support
   --disable-threads       disable async thread support],
@@ -464,22 +457,18 @@ AC_SUBST(DEBUG_CFLAGS)
 AC_SUBST(WFLAGS)
 AC_SUBST(CFLAG_RUNTIME_LIBRARY_PATH)
 
-AC_CHECK_SIZEOF(void *, $erl_xcomp_void_p) # Needed for ARCH and smp checks below
+AC_CHECK_SIZEOF(void *) # Needed for ARCH and smp checks below
 
 dnl
 dnl Figure out operating system and cpu architecture
 dnl
 
-if test "x$erl_xcomp_os" != "x"; then
-    chk_opsys_=$erl_xcomp_os
+if test "x$host_alias" != "x"; then
+    chk_opsys_=$host_os
 else
-    if test "x$host_os" = "xwin32"; then
-	chk_opsys_=win32
-    else
-	chk_opsys_=`uname -s`
-	if test "x$chk_opsys_" = "xSunOS"; then
-	    chk_opsys_=$chk_opsys_`uname -r`
-	fi
+    chk_opsys_=`uname -s`
+    if test "x$chk_opsys_" = "xSunOS"; then
+	chk_opsys_=$chk_opsys_`uname -r`
     fi
 fi
 case $chk_opsys_ in
@@ -491,11 +480,12 @@ case $chk_opsys_ in
     *)				OPSYS=noopsys
 esac
 
-if test "x$erl_xcomp_hw" != "x"; then
-    chk_arch_=$erl_xcomp_hw
+if test "x$host_alias" != "x" -a "x$host_cpu" != "x"; then
+    chk_arch_=$host_cpu
 else
     chk_arch_=`uname -m`
 fi
+
 case $chk_arch_ in
     sun4u)	ARCH=ultrasparc;;
     sparc64)	ARCH=sparc64;;
@@ -1296,11 +1286,11 @@ dnl Interactive UX needs <net/errno.h> for socket related error codes.
 dnl Some Linuxes needs <sys/socketio.h> instead of <sys/sockio.h>
 dnl
 AC_CHECK_HEADERS(fcntl.h limits.h unistd.h syslog.h dlfcn.h ieeefp.h \
-                 sys/stropts.h sys/sysctl.h \
+                 sys/types.h sys/stropts.h sys/sysctl.h \
                  sys/ioctl.h sys/time.h sys/uio.h \
                  sys/socket.h sys/sockio.h sys/socketio.h \
                  net/errno.h malloc.h mach-o/dyld.h arpa/nameser.h \
-		 pty.h util.h utmp.h langinfo.h)
+		 pty.h util.h utmp.h langinfo.h poll.h)
 
 AC_CHECK_HEADER(sys/resource.h,
 	[AC_DEFINE(HAVE_SYS_RESOURCE_H, 1,
@@ -1389,11 +1379,13 @@ LM_STRUCT_SOCKADDR_SA_LEN
 LM_STRUCT_EXCEPTION
 
 AC_CHECK_SIZEOF(char, 1)
-AC_CHECK_SIZEOF(short, $erl_xcomp_short)
-AC_CHECK_SIZEOF(int, $erl_xcomp_int)
-AC_CHECK_SIZEOF(long, $erl_xcomp_long)
-AC_CHECK_SIZEOF(void *, $erl_xcomp_void_p)
-AC_CHECK_SIZEOF(long long, $erl_xcomp_long_long)
+AC_CHECK_SIZEOF(short)
+AC_CHECK_SIZEOF(int)
+AC_CHECK_SIZEOF(long)
+AC_CHECK_SIZEOF(void *)
+AC_CHECK_SIZEOF(long long)
+AC_CHECK_SIZEOF(size_t)
+AC_CHECK_SIZEOF(off_t)
 
 BITS64=
 
@@ -1457,71 +1449,26 @@ int main(void)
     abort ();
   return 0;
 }
-],AC_MSG_RESULT(no)
-,AC_MSG_RESULT(yes)
-AC_MSG_ERROR([This gcc miscompiles the Erlang runtime system; please use a different version])
-,AC_MSG_RESULT(no))
-fi
-
-dnl AC_CHECK_SIZEOF(size_t, 4)dnl Assumes all cross compiling is to 32bit uP
-dnl
-dnl The disabled one above does not include stddef.h, alas!
-dnl
-AC_CACHE_CHECK([size of size_t], ac_cv_sizeof_size_t, 
-AC_TRY_RUN([
-#include <sys/types.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <stddef.h>
-int main(int argc, char **argv) {
-    FILE *f = fopen("conftestval", "w");
-    if (! f)
-	exit(1); /* Failed */
-    fprintf(f, "%d\n", (int) sizeof(size_t));
-    exit(0); /* OK */
-}
-], ac_cv_sizeof_size_t=`cat conftestval`
-,  ac_cv_sizeof_size_t=0
-,  ac_cv_sizeof_size_t=$erl_xcomp_sizeof_size_t))
-AC_DEFINE_UNQUOTED(SIZEOF_SIZE_T, $ac_cv_sizeof_size_t, [The number of bytes in a size_t])
+], gcc_4_3_0_bug=no, gcc_4_3_0_bug=yes, gcc_4_3_0_bug=cross)
+
+case $gcc_4_3_0_bug in
+	yes|no)
+		gcc_4_3_0_bug_result=$gcc_4_3_0_bug;;
+	cross)
+		gcc_dumped_vsn=`$CC -dumpversion 2>/dev/null`
+		case gcc-$gcc_dumped_vsn in
+			gcc-4.3.0) gcc_4_3_0_bug=yes;;
+			*) gcc_4_3_0_bug=no;;
+		esac
+		gcc_4_3_0_bug_result="$gcc_4_3_0_bug; could not run test since cross compiling, checked version number ($gcc_dumped_vsn) instead";;
+esac
 
-dnl A standard size check does not include sys/types.h
-dnl
-AC_CACHE_CHECK([size of off_t], ac_cv_sizeof_off_t, 
-AC_TRY_RUN([
-#include <sys/types.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <stddef.h>
-int main(int argc, char **argv) {
-    FILE *f = fopen("conftestval", "w");
-    if (! f)
-	exit(1); /* Failed */
-    fprintf(f, "%d\n", (int) sizeof(off_t));
-    exit(0); /* OK */
-}
-], ac_cv_sizeof_off_t=`cat conftestval`
-,  ac_cv_sizeof_off_t=0
-,  ac_cv_sizeof_off_t=$erl_xcomp_sizeof_off_t))
-AC_DEFINE_UNQUOTED(SIZEOF_OFF_T, $ac_cv_sizeof_off_t,
-	[The number of bytes in an off_t])
+AC_MSG_RESULT([$gcc_4_3_0_bug_result])
+if test $gcc_4_3_0_bug = yes; then
+	AC_MSG_ERROR([This gcc miscompiles the Erlang runtime system; please use a different version])	
+fi
 
-AC_MSG_CHECKING([int/long/void*/size_t sizes])
-AC_TRY_RUN([
-#include <stdlib.h>
-#include <stddef.h>
-int main(int argc, char **argv) {
-    if (sizeof(void *) >= 4 &&
-	sizeof(void *) == sizeof(size_t) &&
-	(sizeof(void *) == sizeof(int) || sizeof(void *) == sizeof(long))) {
-	exit(0); /* OK */
-    }
-    exit(1); /* Failed */
-}
-],AC_MSG_RESULT(ok)
-,AC_MSG_RESULT(failed)
-AC_MSG_ERROR([Cannot handle this combination of int/long/void*/size_t sizes])
-,AC_MSG_RESULT(ok))
+fi
 
 if test "x$erl_xcomp_bigendian" != "x"; then
 	ac_cv_c_bigendian=$erl_xcomp_bigendian
@@ -1582,7 +1529,7 @@ AC_CHECK_FUNCS([ieee_handler fpsetmask finite isnan isinf res_gethostbyname dlop
 		pread pwrite writev memmove strerror strerror_r strncasecmp \
 		gethrtime localtime_r gmtime_r mremap memcpy mallopt \
 		sbrk _sbrk __sbrk brk _brk __brk \
-		flockfile fstat strlcpy strlcat setsid posix2time setlocale nl_langinfo])
+		flockfile fstat strlcpy strlcat setsid posix2time setlocale nl_langinfo poll])
 if test "X$host" = "Xwin32"; then
 	ac_cv_func_setvbuf_reversed=yes
 fi
@@ -1858,9 +1805,11 @@ int main(void)
 	erts_cv___after_morecore_hook_can_track_malloc=no,
 	if test "x$erl_xcomp_after_morecore_hook" != "x"; then
 		erts_cv___after_morecore_hook_can_track_malloc=$erl_xcomp_after_morecore_hook
+	else
+		erts_cv___after_morecore_hook_can_track_malloc=no
 	fi)])
 
-if test "x$erts_cv___after_morecore_hook_can_track_malloc" = "xyes"; then
+if test $erts_cv___after_morecore_hook_can_track_malloc = yes; then
 	AC_DEFINE(ERTS___AFTER_MORECORE_HOOK_CAN_TRACK_MALLOC, 1, \
 [Define if __after_morecore_hook can track malloc()s core memory use.])
 fi
@@ -2116,7 +2065,11 @@ int main(void)
 	],
 	    erts_cv_brk_wrappers_can_track_malloc=yes,
 	    erts_cv_brk_wrappers_can_track_malloc=no,
-	    erts_cv_brk_wrappers_can_track_malloc=no)])
+	    if test "x$erl_xcomp_dlsym_brk_wrappers" != "x"; then
+		erts_cv_brk_wrappers_can_track_malloc=$erl_xcomp_dlsym_brk_wrappers
+	    else
+		erts_cv_brk_wrappers_can_track_malloc=no
+	    fi)])
 	if test $erts_cv_brk_wrappers_can_track_malloc = yes; then
 		AC_DEFINE(ERTS_BRK_WRAPPERS_CAN_TRACK_MALLOC, 1, \
 [Define if sbrk()/brk() wrappers can track malloc()s core memory use])
@@ -2643,7 +2596,14 @@ int main(int argc, const char **argv)
     do_fmul();
     return do_check();
 }
-], erl_ok=reliable, erl_ok=unreliable, erl_ok=unreliable)
+],
+erl_ok=reliable,
+erl_ok=unreliable,
+if test "x$erl_xcomp_reliable_fpe" = "xyes"; then
+	erl_ok=reliable
+else
+	erl_ok=unreliable
+fi)
     if test $erl_ok = unreliable; then
         AC_DEFINE(NO_FPE_SIGNALS,[],
 	    [Define if floating points exceptions are non-existing/not reliable])
@@ -2826,9 +2786,12 @@ fi
 # Check for working poll().
 #
 AC_MSG_CHECKING([for working poll()])
-if test "x$erl_xcomp_poll" != "x"; then
-	poll_works=$erl_xcomp_poll
+if test "x$ac_cv_header_poll_h" != "xyes" -o "x$ac_cv_func_poll" != "xyes"; then
+
+poll_works=no
+
 else
+
 AC_TRY_RUN([
 #include <poll.h>
 main()
@@ -2848,23 +2811,43 @@ main()
   exit(0);
 #endif
 }
-], poll_works=true, poll_works=false, poll_works=false)
+],
+poll_works=yes,
+poll_works=no,
+poll_works=$erl_xcomp_poll)
+
+if test "X$poll_works" != "X"; then
+	guessed_poll_works=no
+else
+	guessed_poll_works=yes
+	case $host_os in
+		darwin*) poll_works=no;;
+		*) poll_works=yes;;
+	esac
+fi
+
 fi
+
 case $poll_works in
-true)
+yes)
 	AC_DEFINE(ERTS_USE_POLL, 1, [Define if poll() should be used instead of select()])
-	AC_MSG_RESULT(ok)
+	AC_MSG_RESULT(yes)
 	;;
 *)
 	#
 	# The USE_SELECT define is used by the ssl application (should not
 	# be used by erts).
 	#
+	poll_works=no
 	AC_DEFINE(USE_SELECT, 1, [Define if select() should be used instead of poll()])
-	AC_MSG_RESULT(broken or based on select())
+	AC_MSG_RESULT([no; non-existing, broken, or based on select()])
 	;;
 esac
 
+if test $guessed_poll_works = yes; then
+	AC_MSG_WARN([result $poll_works guessed based on OS ($host_os) because of cross compilation])
+fi
+
 #
 # If kqueue() found, check that it can be selected or polled on...
 #
@@ -2900,7 +2883,14 @@ int main(void) {
     }
     return 0;
 }
-	], ok_kqueue=true, ok_kqueue=false, ok_kqueue=false)
+	],
+	ok_kqueue=true,
+	ok_kqueue=false,
+	if test "x$erl_xcomp_kqueue" = "xyes"; then
+		ok_kqueue=true
+	else
+		ok_kqueue=false
+	fi)
 	if test $ok_kqueue = true; then
 		AC_MSG_RESULT(yes);
 	else
@@ -2990,7 +2980,15 @@ int main(void) {
 	    return 5;
     return 0;
 }
-], copying_putenv=yes, copying_putenv=no, copying_putenv=no)
+],
+copying_putenv=yes,
+copying_putenv=no,
+if test "x$erl_xcomp_putenv_copy" != "x"; then
+	copying_putenv=$erl_xcomp_putenv_copy
+else
+	copying_putenv=no
+fi)
+
 if test $copying_putenv = yes; then
 	AC_DEFINE(HAVE_COPYING_PUTENV,[1],[Define if you have a putenv() that stores a copy of the key-value pair])
 fi
diff --git a/erts/emulator/beam/sys.h b/erts/emulator/beam/sys.h
index 71cb6a36cc..4b949523fa 100644
--- a/erts/emulator/beam/sys.h
+++ b/erts/emulator/beam/sys.h
@@ -239,6 +239,11 @@ EXTERN_FUNCTION(int, real_printf, (const char *fmt, ...));
 ** Sint16: A signed integer of 16 bits exactly.
 */
 
+#if !((SIZEOF_VOID_P >= 4) && (SIZEOF_VOID_P == SIZEOF_SIZE_T) \
+      && ((SIZEOF_VOID_P == SIZEOF_INT) || (SIZEOF_VOID_P == SIZEOF_LONG)))
+#error Cannot handle this combination of int/long/void*/size_t sizes
+#endif
+
 #if SIZEOF_VOID_P == 8
 #undef  ARCH_32
 #define ARCH_64