Line number error on IA32

Imported from http://bugzilla.roxen.com/bugzilla/show_bug.cgi?id=3004

Reported by Martin Nilsson, IDA nilsson@pike.ida.liu.se

From the testsuite:

testsuite: Test 9971 (shift 2) Line numbering failed.
  1:  object(LR.parser) p=LR.Grammar_parser.make_parser("foo : bar;foo :
foo bar;bar : \"a\";"); int pos; array(string) data="aaaaaaaaa"/""; string
scan() { if (pos < sizeof(data)) return(data[pos++]); else return ""; } int
a() { return(p->parse(scan) == "a"); }
  2: int __cpp_line=__LINE__; int __rtl_line=[int]backtrace()[-1][1];
   CPP lines: 2
   RTL lines: 1
Actual lines: 2