Disagreement between gcc and gdb about the size of an addr
causes numerous dwarf2-related complaints of the form:

(gdb) advance foo^M
foo (a=dwarf2_read_address: Corrupted DWARF expression.^M
) at 
/opt/redhat/gnupro-06r1-1/sources/tools/cross/gdb/testsuite/gdb.base/advan\ce.c:6^M
6         int b = a + 10;^M
(gdb) FAIL: gdb.base/advance.exp: advance function called as param