+ *) CPUFAM=nil ABI=nil ;;
+esac
+
+dnl Now check the assembler. We have target-specific requirements here, so
+dnl we couldn't do this any earlier.
+AC_CACHE_CHECK(
+ [whether the assembler is likely to work], [mdw_cv_gnuish_as],
+ [AC_LANG_PUSH([CPPAS])
+ AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
+ .text
+ .L\$_test = 23
+.macro mymac
+ .L\$_test = .L\$_test + 1
+.endm
+ .globl foo
+ .extern bar
+ mymac]])],
+ [mdw_cv_gnuish_as=yes], [mdw_cv_gnuish_as=no])
+ case $CPUFAM in
+ x86 | amd64)
+ AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
+ .text
+ .arch pentium4
+ .intel_syntax noprefix
+ .globl foo
+foo:
+ adcd var, 0
+ ret
+ .data
+var: .long 1
+ ]])],
+ [:], [mdw_cv_gnuish_as=no])
+ ;;
+ esac
+ AC_LANG_POP([CPPAS])])
+AM_CONDITIONAL([GNUISH_AS], [test $mdw_cv_gnuish_as = yes])
+if test $mdw_cv_gnuish_as = no; then CPUFAM=nil ABI=nil; fi
+
+dnl A hairy macro used to set the `CPUFAM_...' and `ABI_...' variables. We
+dnl basically need to do the same thing for the family and ABI, so it's worth
+dnl some effort to hide the ugliness.
+m4_define([catacomb_DEFINE_CPU_OR_ABI],
+[case $$1 in
+ m4_define([_def],
+ [m4_ifdef([catacomb_seen_$3/$$2], [],
+ [$$2)
+ AC_DEFINE([$4]m4_translit([$$2], [a-z], [A-Z]), [1], [$5])
+ ;;m4_define([catacomb_seen_$3/$$2], [t])])])
+ catacomb_CPU_FAMILIES([_def])
+ nil) ;;
+ *) AC_MSG_ERROR([BUG: unexpected $1 \`$1']) ;;
+esac])
+
+dnl Now that's out the way, we can explain what we're doing.
+AC_MSG_CHECKING([CPU family and ABI])
+
+dnl Figure out the target CPU family and ABI.
+catacomb_CPU_FAMILIES([catacomb_CLEAR_FLAGS])
+catacomb_DEFINE_CPU_OR_ABI([CPUFAM], [2], [cpu],
+ [CPUFAM_], [Define if target CPU is \`$][2\'.])
+catacomb_DEFINE_CPU_OR_ABI([ABI], [3], [abi],
+ [ABI_], [Define if target ABI is \`$][3\'.])
+
+dnl Establish Automake conditions for things.
+catacomb_CPU_FAMILIES([catacomb_CLEAR_FLAGS])
+m4_define([catacomb_COND_CPU],
+[m4_define([_CPU], m4_translit([$2], [a-z], [A-Z]))
+m4_define([_ABI], m4_translit([$3], [a-z], [A-Z]))
+AM_CONDITIONAL([CPUABI_]_CPU[_]_ABI, [test x$CPUFAM/$ABI = x$2/$3])
+m4_ifdef([catacomb_seen_cpu/$2], [],
+[AM_CONDITIONAL([CPUFAM_]_CPU, [test x$CPUFAM = x$2])dnl
+m4_define([catacomb_seen_cpu/$2], [t])])
+m4_ifdef([catacomb_seen_abi/$3], [],
+[AM_CONDITIONAL([ABI_]_ABI, [test x$ABI = x$3])dnl
+m4_define([catacomb_seen_abi/$3], [t])])])
+catacomb_CPU_FAMILIES([catacomb_COND_CPU])
+AM_CONDITIONAL([KNOWN_CPUFAM], [test x$CPUFAM != xnil])
+
+dnl Report on what we found.
+case $CPUFAM in
+ nil) AC_MSG_RESULT([not supported]) ;;
+ *) AC_MSG_RESULT([$CPUFAM/$ABI]) ;;