[RFC] The never ending 32-bit vs. 64-bit blues

[Mark Kettenis <mark.kettenis@xs4all.nl>]

In the past we have had a lot of bug reports from people trying to
debug 64-bit programs with a native 32-bit gdb.  As far as I know we
don't support any native configuration that allows this.  I've never
quite managed to come up with a satisfactory solution to deal with
this.  Here's an attempt to deal with it by making configure complain.

Any opinions about this?

Mark


Index: configure.ac
===================================================================
RCS file: /cvs/src/src/gdb/configure.ac,v
retrieving revision 1.24
diff -u -p -r1.24 configure.ac
--- configure.ac	25 Jul 2005 15:08:40 -0000	1.24
+++ configure.ac	7 Nov 2005 22:34:19 -0000
@@ -34,6 +34,19 @@ AM_PROG_CC_STDC
 AC_CONFIG_AUX_DIR(`cd $srcdir;pwd`/..)
 AC_CANONICAL_SYSTEM
 
+# Sanity check; refuse to build a native GDB for a 64-bit target with
+# a 32-bit compiler.
+AC_CHECK_SIZEOF(void *)
+if test "${target}" = "${host}"; then
+  case "$host_cpu" in
+  hppa64|mips64*|powerpc64|sparc64|x86_64)
+    if test $ac_cv_sizeof_void_p != 8; then
+      AC_MSG_ERROR(
+[building native target ${host} with a 32-bit compiler is not supported])
+    fi
+  esac
+fi
+
 dnl List of object files and targets accumulated by configure.
 
 CONFIG_OBS=