[Bug preprocessor/51745] Strange symbol appears when using commandline definition without "="

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51745

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-01-03 
21:48:19 UTC ---
In other words:

$ echo foo | gcc -E - -o - "-Dfoo bar"
# 1 "<stdin>"
# 1 "<built-in>"
# 1 "<command-line>"
# 1 "<stdin>"
bar 1