Give ICC its preferred, documented form of the no-strict-aliasing

switch, viz '-fno-alias'.  Since we have a separate code path here
anyway, it's just as easy to cooperate.

configure

@@ -3120,11 +3120,11 @@ echo "${ECHO_T}no" >&6
 fi
 rm -f conftest.err conftest.$ac_objext conftest.$ac_ext
 
-  # Not clear if this is needed, but seems like a good idea
-  echo "$as_me:$LINENO: checking if $CC supports -fno-strict-aliasing" >&5
-echo $ECHO_N "checking if $CC supports -fno-strict-aliasing... $ECHO_C" >&6
+  # ICC prefers to spell the no-strict-aliasing switch like this
+  echo "$as_me:$LINENO: checking if $CC supports -fno-alias" >&5
+echo $ECHO_N "checking if $CC supports -fno-alias... $ECHO_C" >&6
 pgac_save_CFLAGS=$CFLAGS
-CFLAGS="$pgac_save_CFLAGS -fno-strict-aliasing"
+CFLAGS="$pgac_save_CFLAGS -fno-alias"
 cat >conftest.$ac_ext <<_ACEOF
 /* confdefs.h.  */
 _ACEOF

configure.in

 dnl Process this file with autoconf to produce a configure script.
-dnl $PostgreSQL: pgsql/configure.in,v 1.524 2007/08/20 08:53:12 petere Exp $
+dnl $PostgreSQL: pgsql/configure.in,v 1.525 2007/09/11 19:50:25 tgl Exp $
 dnl
 dnl Developers, please strive to achieve this order:
 dnl
@@ -291,8 +291,8 @@ elif test "$ICC" = yes; then
   # Intel's compiler has a bug/misoptimization in checking for
   # division by NAN (NaN == 0), -mp1 fixes it, so add it to the CFLAGS.
   PGAC_PROG_CC_CFLAGS_OPT([-mp1])
-  # Not clear if this is needed, but seems like a good idea
-  PGAC_PROG_CC_CFLAGS_OPT([-fno-strict-aliasing])
+  # ICC prefers to spell the no-strict-aliasing switch like this
+  PGAC_PROG_CC_CFLAGS_OPT([-fno-alias])
 elif test x"${CC}" = x"xlc"; then
   # AIX xlc has to have strict aliasing turned off too
   PGAC_PROG_CC_CFLAGS_OPT([-qnoansialias])