Fixed cross-compiling with the default options.

The failmalloc check doesn't make sense when cross-compiling, and
configure even errored out in this case.

m4m/failmalloc.m4

@@ -3,11 +3,14 @@ AC_DEFUN([CHECK_FAILMALLOC],[dnl
   dnl Libtool sets the default library paths
   AM_PROG_LIBTOOL
   path_provided=
+  failmalloc_requested=  dnl Either implicitly or explicitly
   AC_ARG_WITH(failmalloc, [  --with-failmalloc=PATH  use Failmalloc for tests], [
-      if test x"$withval" = "x" -o x"$withval" = "xyes"; then
+      failmalloc_requested=1
+      if test x"$withval" = "x" -o x"$withval" = x"yes"; then
         failmalloc_search_path="$sys_lib_search_path_spec"
-      elif test x"$withval" = "xno"; then
+      elif test x"$withval" = x"no"; then
         failmalloc_search_path=""
+        failmalloc_requested=
       else
         failmalloc_search_path="$withval"
         path_provided=1
@@ -16,17 +19,22 @@ AC_DEFUN([CHECK_FAILMALLOC],[dnl
   )
   libfailmalloc_file=libfailmalloc.so.0
   FAILMALLOC_PATH=
-  dnl Check if the argument is a directory
-  for d in $failmalloc_search_path; do
-      AC_CHECK_FILE([$d/$libfailmalloc_file], [
-        FAILMALLOC_PATH="$d/$libfailmalloc_file"
-        break
-      ], [])
-  done
-  if test -z "$FAILMALLOC_PATH" -a -n "$path_provided"; then
-    dnl Check if the argument is a file
-    AC_CHECK_FILE([$failmalloc_search_path], [FAILMALLOC_PATH="$failmalloc_search_path"], [])
+
+  dnl Skip the check if we're cross-compiling, unless the user explicitly requested it
+  if test x"$cross_compiling" = x"no" -o x"$failmalloc_requested" = x"1"; then
+    dnl Check if the argument is a directory
+    for d in $failmalloc_search_path; do
+        AC_CHECK_FILE([$d/$libfailmalloc_file], [
+          FAILMALLOC_PATH="$d/$libfailmalloc_file"
+          break
+        ], [])
+    done
+    if test -z "$FAILMALLOC_PATH" -a -n "$path_provided"; then
+      dnl Check if the argument is a file
+      AC_CHECK_FILE([$failmalloc_search_path], [FAILMALLOC_PATH="$failmalloc_search_path"], [])
+    fi
   fi
+
   AC_MSG_CHECKING([for failmalloc])
   dnl Make sure AC_CHECK_FILE didn't find a directory by mistake
   if test -n "$FAILMALLOC_PATH" -a -f "$FAILMALLOC_PATH"; then
@@ -35,10 +43,14 @@ AC_DEFUN([CHECK_FAILMALLOC],[dnl
     if test -n "$path_provided"; then
       AC_MSG_ERROR([$libfailmalloc_file was not found at $failmalloc_search_path])
     else
-      AC_MSG_RESULT([no])
+      if test x"$cross_compiling" != x"no"; then
+        AC_MSG_RESULT([no (cross compiling)])
+      else
+        AC_MSG_RESULT([no])
+      fi
     fi
   fi
   AC_SUBST(FAILMALLOC_PATH)
-  AM_CONDITIONAL(USE_FAILMALLOC, [test "x$FAILMALLOC_PATH" != "x"])
+  AM_CONDITIONAL(USE_FAILMALLOC, [test x"$FAILMALLOC_PATH" != x])
 ])