+# On PPC, check if assembler supports LWARX instruction's mutex hint bit
+case $host_cpu in
+ ppc*|powerpc*)
+ AC_MSG_CHECKING([whether assembler supports lwarx hint bit])
+ AC_TRY_COMPILE([],
+ [int a = 0; int *p = &a; int r;
+ __asm__ __volatile__ (" lwarx %0,0,%1,1\n" : "=&r"(r) : "r"(p));],
+ [pgac_cv_have_ppc_mutex_hint=yes],
+ [pgac_cv_have_ppc_mutex_hint=no])
+ AC_MSG_RESULT([$pgac_cv_have_ppc_mutex_hint])
+ if test x"$pgac_cv_have_ppc_mutex_hint" = xyes ; then
+ AC_DEFINE(HAVE_PPC_LWARX_MUTEX_HINT, 1, [Define to 1 if the assembler supports PPC's LWARX mutex hint bit.])
+ fi
+ ;;
+esac
+
+# Check largefile support. You might think this is a system service not a
+# compiler characteristic, but you'd be wrong. We must check this before
+# probing existence of related functions such as fseeko, since the largefile
+# defines can affect what is generated for that.
+if test "$PORTNAME" != "win32"; then
+ AC_SYS_LARGEFILE
+fi
+
+# Check for largefile support (must be after AC_SYS_LARGEFILE)
+AC_CHECK_SIZEOF([off_t])
+
+# If we don't have largefile support, can't handle segsize >= 2GB.
+if test "$ac_cv_sizeof_off_t" -lt 8 -a "$segsize" != "1"; then
+ AC_MSG_ERROR([Large file support is not enabled. Segment size cannot be larger than 1GB.])
+fi
+